Post by: Uniflow on January 31, 2013, 04:42:01 AM
Here are four castings I've had done, they have been heat treated to T6.
These only turned up today, so I'll have to get to machining them next week or so. One of these is for the YZ 250 EFI project the rest are spares.
Post by: citabjockey on January 31, 2013, 05:03:51 AM
Post by: eprovenzano on January 31, 2013, 01:42:53 PM
Watching with keen interest!
X2
Post by: SachsGS on January 31, 2013, 03:41:56 PM
Post by: yota on January 31, 2013, 03:44:34 PM
Post by: jimaras Greece on January 31, 2013, 05:53:50 PM
Post by: Uniflow on January 31, 2013, 09:15:33 PM
BTW Lozza, part of the reason the bighorn kicks sideways is the rear wheel is moving 10mm side to side!! I need to replace the bronze swing arm bush with an aluminium bronze bush, much harder.
The fuel pump is the problem as it draws just over four amps all the time, even when the engine is idleing. It is a standard car HP pump so delivers way more flow than needed. I'll need to find something a little smaller for the YZ project. Fourstroke MX bike pumps look very similar to mine, big and heavy. That's just a waste of energy!! The YZ project flywheel and stator are late model rare earth magnet type, this will help, smaller too.
Post by: Stusmoke on January 31, 2013, 09:41:57 PM
Watching with keen interest!
X2
x 999.
can't wait man best of luck.
Post by: Formerly knownas Premixed on January 31, 2013, 11:33:11 PM
What are you using for management? Microsquirt?
Post by: cnrcpla on January 31, 2013, 11:44:53 PM
Post by: Uniflow on February 01, 2013, 06:41:17 AM
Just found a smaller pump today 2 amps usage and still an external type.
I'm not quite sure if it is apparent but I've got two YZ projects on the go. One is the standard YZ250 converted to EFI ( for the local Yamaha dealer).
The other in the YZ250F frame with my own 360 engine, cases are cast and machined to suit the YZF frame so no cutting is required. This engine has vairable rotary valve, blade type power valve, reverse rotating crank and reverse cylinder. This engine will uses the vairable valve casing as the throttle, driven from the link computer ( throttle by wire ). Much better engine control!
Cut the first engine case pattern today in the CNC. I will be using castings.
Post by: 2T Institute on February 01, 2013, 06:44:35 AM
Post by: Uniflow on February 01, 2013, 07:15:55 AM
Although Frits did suggest moving both sides of the port. I hadn't thought of that.
Post by: Uniflow on February 01, 2013, 08:03:46 AM
Machined up one casting today, just need to build the drum now. This will be shelled by the CNC, 2mm wall to make it light. Little hole is for oil line if needed. Lug on the back will be machined to accept the TPS. Drum runs on ball bearings nothing touches the wall. This is for the YZ250 project.
Post by: Uniflow on February 01, 2013, 08:08:34 AM
Here is the first pattern to be roughed out, engine will be using a YZ250 clutch and gearbox.
This is the YZ360 VRV project.
Post by: Jeram on February 01, 2013, 08:29:53 AM
Post by: Davo on February 01, 2013, 10:42:26 AM
Have you looked at something like this for reducing the draw of the fuel pump at low rpm if its still an issue?... http://www.madhu.com/content/Main/FuelPumpController
Post by: 2T Institute on February 01, 2013, 12:25:36 PM
Post by: Uniflow on February 01, 2013, 08:24:13 PM
Post by: Formerly knownas Premixed on February 01, 2013, 10:47:05 PM
I'll be using the Link, same as my Bighorn, it works well. Link are releasing a special version for the two stroke ( from my input ) middle of the year. At last!!!
Just found a smaller pump today 2 amps usage and still an external type.
I'm not quite sure if it is apparent but I've got two YZ projects on the go. One is the standard YZ250 converted to EFI ( for the local Yamaha dealer).
The other in the YZ250F frame with my own 360 engine, cases are cast and machined to suit the YZF frame so no cutting is required. This engine has vairable rotary valve, blade type power valve, reverse rotating crank and reverse cylinder. This engine will uses the vairable valve casing as the throttle, driven from the link computer ( throttle by wire ). Much better engine control!
Cut the first engine case pattern today in the CNC. I will be using castings.
If what you say in this post is true, and materializes, its going to be pretty amazing. I'm going to keep my eye out for Link.
Is it a do-it-yourself breadboard type kit like Megasquirt, or is it 100% plug-and-play? price range?
http://www.linkecu.com/
Post by: Uniflow on February 02, 2013, 03:23:52 AM
) they do work with twostroke snowmobiles already. The change is to suit transfer port injection. Not sold as a kit, they are ready to use just need setting up to the engine you want to put it on. Approx $1300 NZD for the ECU. Link have been around for probably thirty years or more, good company to deal with, very helpful.
Post by: Uniflow on February 23, 2013, 07:49:55 AM
Post by: TMKIWI on February 23, 2013, 07:56:08 AM
Did you get any photos from Aria ?
Post by: vetman on February 23, 2013, 08:14:39 AM
Post by: Uniflow on February 23, 2013, 09:14:56 AM
vetman, yes saw the EFI 500 bike at a trail ride two weeks ago at Whakatane ( NZ ), only it's sporting a carburator now! Owner said that they had had so much trouble that they had tossed the EFI. He said to me you can't EFI a twostroke MX bike. Interesting as that's not what was said on the Youtube clip.
Whoever set the bike up made the same mistake everyone seems to, inject into the inlet. He said that they could never get it to run right up to 1/3 throttle. My Kawasaki will pull clean and crisp from off idle, inject into transfers not the inlet, been there done that.
Post by: metal_miracle on February 23, 2013, 02:17:15 PM
but this really peak my interest. looking good
Post by: _X_ on February 23, 2013, 03:00:24 PM
Post by: scotty dog on February 26, 2013, 10:00:39 PM
Post by: Jeram on February 27, 2013, 03:34:50 AM
Im assuming that your going to then build the optimum bell mouth for that throttle body to increase the CFM by a further 10% ?
Post by: Uniflow on February 27, 2013, 09:19:57 AM
This throttle body you see here is to fit into the space on a YZ250 where the carb was. It still needs some machining to the inlet where the air box rubber boot fits. Cylinder still needs the injectors fitting, I've welded lugs on but not machined them yet. For some reason we are loaded with work at the moment ( you know real bill paying work ) and these jobs have to take a back seat.
In saying that I've set aside this weekend as a YZ360 cases patten, weekend.
Post by: Lolerbabop on February 27, 2013, 11:45:51 AM
Post by: Jeram on February 27, 2013, 09:01:31 PM
Jearm, we still haven't done your job yet!! Sorry, we have had some deadlines to meet ( you know, the work that pays the bills ). Phillip tells me the drawing is not quite on center. I think he has adjusted the drawing to suit now. Phillip will look at Monday or Tuesday to put your job through.
This throttle body you see here is to fit into the space on a YZ250 where the carb was. It still needs some machining to the inlet where the air box rubber boot fits. Cylinder still needs the injectors fitting, I've welded lugs on but not machined them yet. For some reason we are loaded with work at the moment ( you know real bill paying work ) and these jobs have to take a back seat.
In saying that I've set aside this weekend as a YZ360 cases patten, weekend.
Ah fair enough, i forgot this one is going on a stock YZ250!
when its disc valve will you run a trick airbox on the side of the motor like the aprilia GP bikes?
If there were any errors in my CNC CAD drawing thank Phillip for finding them before it was too late
tell him as long as it has a 20mm butterfly and the same ID/OD for the exhaust pipe/cylinder mounting etc he is welcome to fiddle with it to his hearts content.
Looking forward to seeing the disc valve 360 cases! If I didnt already have as million and 1 projects Id buy one
Post by: Uniflow on February 28, 2013, 01:41:23 AM
Post by: Jeram on February 28, 2013, 11:59:05 PM
be sure to use the bell mouth forumulas!
Also if you want to try something else trick, make sure there is a little bit of clearance inside the cases so that you can use the insulating paint talked about on pit-lane.biz, part 2, page 39
Post by: Uniflow on March 02, 2013, 08:34:13 AM
It's taken all weekend but here is one case pattern, split on the part line, rotary valve port will be CNC cut straight into the casting when it's being machined ( better finish and more accurate ). There will be a cover machined and bolted over the lightening pockets, where the rotary valve sits. This will be the inside rotary valve face and made of or plated with something slippery. Next will be the left hand case.
I will be painting these patterns.
All machined at three degrees taper.
Post by: Jeram on March 02, 2013, 11:43:26 AM
Post by: Uniflow on March 08, 2013, 11:21:06 PM
Suitable bike to use, not cleaned from last ride!!
Injectors in place, still need to make the fuel rail. This will be connected to some head studs.
All the bits are starting to come together for the YZ250 EFI project.
Post by: Stusmoke on March 08, 2013, 11:27:22 PM
Post by: 2T Institute on March 09, 2013, 01:16:09 AM
Making it disc valve is a master stroke, pissing those flapping reeds off is brilliant. Did you end up incorporating a balance shaft?
Post by: bigred1977 on March 09, 2013, 10:49:34 AM
i would just like to add my ten cents worth regarding the yzr500fi. i feel its only right as i was the person who designed and built the whole bike, including its efi system.
the reason the bike ever eventuated in the first place was due to the fact, myself and my partner agreed to do it for free! yes for free.
the owner keith patterson who is now sporting a carburettor on the very same bike was the biggest hurdle in the whole venture.
frankly speaking the man is thick as two short planks and no amount of explaining or lodgic will ever sink in.
the reason he pulled the efi off the bike was down to being a tight arse, he would not shell out $600 for a stator capable of the current draw on the efi, so when batt voltage dropped below a certain threshold the bike word run ****. simple stuff. not for keith.
any how i turned my back on him. and now reside in australia, i have made numerous kits that all work fantastic, all port injected.
there is alot of time and research into making hybrid systems work such as these, i have no doubt yours will work great too, i can only commend people such as yourself.
i did not want to detract from your thread, however reading the part about the yzr500fi, that had to be put straight.
am intersted to know who you are? where abouts are you located?
cheers mark.
Post by: Stusmoke on March 09, 2013, 11:55:45 AM
Post by: jar944 on March 09, 2013, 02:22:47 PM
Post by: cnrcpla on March 09, 2013, 07:07:53 PM
Post by: Uniflow on March 09, 2013, 07:25:42 PM
I have had a lot of trouble getting the Bighorn to run clean low in the revs until I changed to injecting just before transfer ports opened, I inject into the crank case at the catchment area to the rear port. This was done because I needed to hide the injectors from eyes. As it happened this was exactly the right thing to do. Link are bringing out new soft ware that will make transfer port timing even better. Should be mid this year ( soon! ). I didn't want to down grade your efforts, I just found it surprising that after all that effort to see a carb on the EFI CR500. Incidently the owner says he still can't get the carb to run right, down off idle.
Post by: TMKIWI on March 10, 2013, 06:21:25 AM
You going to Halcombe ?
Post by: GerbilGronk on March 10, 2013, 07:04:44 AM
Post by: Uniflow on March 10, 2013, 07:37:22 AM
Stusmoke, because I have a YZ thats why, just because it's handy.
This post is a little confusing as I'm doing two projects, both on this post.
1 EFI standard YZ250, this will be first as all the parts are here now.
2 Make a 360 rotary valve engine ( EFI ) that fits in an 0010 YZF 250 frame. I call this a YZ360 VRV. ( variable rotary valve ) This engine has a 70mm stroke so can be re cylindered into a 250 if necessary. Maybe it might be competitive??? According to Wobbly's gas flow data on the cylinder, it should be good for between 60 and 70 HP, time will tell? I will definitely need help from other people ( Wobbly / Lozza ) to get this type of power.
Post by: scottydog on March 10, 2013, 09:11:42 AM
I started a EFI project for my YZ 144 but put that in the too hard basket for now.
Are you working out of a machine shop in Tauranga somewhere?
I ask as I need some bike(non motor type) parts CNCed up,
Scott
Post by: 2T Institute on March 10, 2013, 09:17:59 AM
Post by: TMKIWI on March 10, 2013, 10:02:05 AM
Just got a call from Loyd ( Kiwi VMX ) today, seems Halcombe has just been canceled. Too much dust, too dangerous, they are worried someone will get hurt, fair enough. Could you pass this info on to anyone else you know planing to go to Halcombe. Thanks.
****. I just paid my entry fee.
Bloody drought.
Post by: bigred1977 on March 10, 2013, 11:35:27 AM
set at 43 psi on the internal reg to be great, they only drew 1.2 amps at full throttle and at one point took a 1000cc injector to 95 percent duty!! pretty good i thought.am looking forward to your project finishing mate, top stuff.
am interested to see what trigger wheel and cps you end up using? are you going to do a full stand alone with this 250/360 or are you going fuel only?
cheers mark.
Post by: Stusmoke on March 10, 2013, 12:13:29 PM
Post by: _X_ on March 10, 2013, 01:22:01 PM
Post by: 2T Institute on March 10, 2013, 01:27:06 PM
Post by: Uniflow on March 10, 2013, 07:45:23 PM
You haven't ridden a real two stroke until you have ridden a rotary valve engine.
Absolutely !!
Post by: lauterbacher on March 10, 2013, 07:59:48 PM
Post by: 2T Institute on March 10, 2013, 09:40:12 PM
A YZ 250 has about 35kW/ 48Nm torque to get more you need to rev them harder and a radicaly different pipe.
Post by: lauterbacher on March 10, 2013, 10:06:22 PM
Yes I remember your post of the aprilla 125 with the rear rotary valve and 54 horsepower.
Post by: Uniflow on March 10, 2013, 11:16:23 PM
What's up with the injectors aiming downstream?
Secret. Nah, just this is the best way to fit them so as to miss the exhaust pipe. Also some car manufactures claim they get better air / fuel mixture / atomization pointing into the on coming air stream. I would prefer to have them point straight into the cylinder just above the transfer's but that is for the next engine with my own cylinder. Put my own injector lugs where I want them.
Post by: Uniflow on March 10, 2013, 11:23:26 PM
Awesome work uniflow! Think I seen your other bike out Maddix park a while back.
I started a EFI project for my YZ 144 but put that in the too hard basket for now.
Are you working out of a machine shop in Tauranga somewhere?
I ask as I need some bike(non motor type) parts CNCed up,
Scott
Yes probably, you don't see too many Bighorn Kawasaki's around these days. The day you would have seen the Kawasaki the fuel pump split, it only ran for a short while.
I live in Hamilton, machine shop in the yard out the back of the house. Walk to work every morning. We already do a bit of work for Wobbly. Certainly I'm interested but we are very busy at the moment, your job might have to sit in line.
Post by: 2T Institute on March 11, 2013, 02:48:21 AM
Post by: scottydog on March 11, 2013, 09:17:57 AM
Awesome work uniflow! Think I seen your other bike out Maddix park a while back.
I started a EFI project for my YZ 144 but put that in the too hard basket for now.
Are you working out of a machine shop in Tauranga somewhere?
I ask as I need some bike(non motor type) parts CNCed up,
Scott
Yes probably, you don't see too many Bighorn Kawasaki's around these days. The day you would have seen the Kawasaki the fuel pump split, it only ran for a short while.
I live in Hamilton, machine shop in the yard out the back of the house. Walk to work every morning. We already do a bit of work for Wobbly. Certainly I'm interested but we are very busy at the moment, your job might have to sit in line.
Sweet as, what I need is small scale production run of parts I have been using a guy up Waipu ways and just looking at other options.
PM me your email and I'll be in touch
Scott
Post by: TMKIWI on March 15, 2013, 09:23:51 AM
Thought you might find it interesting uniflow.
http://www.arcticinsider.com/Article/Tech-Insight-Inside-the-new-Arctic-Cat-600-C-TEC2-Engine
Post by: factoryX on March 15, 2013, 09:33:45 AM
Post by: Uniflow on March 15, 2013, 09:48:01 AM
Post by: Jeram on March 15, 2013, 01:42:21 PM
There you go, they copied me Not. This system is what I've been on about, transfer port injection. Sort of what my Kawasaki Bighorn is like. The new YZ360 will have a very similar system, but different. See how good EFI can be!! And easy as well, all standard car parts.
Hey uniflow, how much you want to merge these arctic cat crankcases with an 600 supersport clutch and gearbox? I'd happy pay a couple thousand
didnt wobbly try this or do this some time ago? was it through you?
Would be bloody awesome to be able to mount this directly into an R6 or triumph 675 and have a 6 speed gearbox.
Post by: citabjockey on March 15, 2013, 04:20:47 PM
This slot in the piston -- I hope its strong enough at the bottom of the skirt. My SC500 motor had failed for the prior owner from cracks that form from slots in the piston to the bottom of the skirt. This was very common on these motors from what I understand:
That said I am very gratified to see Arctic Cat put out this motor. And to be doing the manufacture in house? Very Cool. Go USA (for once).
Post by: SachsGS on March 15, 2013, 04:40:09 PM
The old aircooled open class mx's ran a lot of piston clearance and you could hear the piston knock until things warmed up. I've got an old Yamaha 400 in the shop right now and it's pretty noisy when it first fires up. I'm pretty sure piston metallurgy has improved quite a bit since those old SC500's.
Post by: neilie on March 15, 2013, 10:35:43 PM
Since you are setting up efi, why not use a big tuning advantage over carbs, that is,Inputting the e.g.t. into the efi and tuning to match the pipe will broaden the peak rpm of the pipe. e.g. colder egt after peak , hotter egt before peak. there could possibly be a point where it can ,as rpm decreases, change from hot to colder but this would require almost instant egt change (maybe this is possible as it does change very quickly). tuning older 2 strokes with an optak was very effective. cheers and all the best
Post by: neilie on March 15, 2013, 10:51:41 PM
Post by: Uniflow on March 15, 2013, 11:56:06 PM
Like this?
Or like this
Post by: HCE on March 16, 2013, 12:42:41 AM
The Arctic Cat functions as a DFI engine at low speeds, correct? I wonder how the Orbital patents are affecting all of this?
Technically it is direct injection at idle, but traditional direct injection refers fuel being injected just before ignition with all ports closed. Also traditional direct injection systems operate at much higher fuel pressures to over come the pressure of the compressed air in the cylinder.
Post by: 2T Institute on March 16, 2013, 02:10:09 AM
Post by: evo550 on March 16, 2013, 06:46:26 AM
Post by: Jeram on March 16, 2013, 08:29:58 AM
Since you are setting up efi, why not use a big tuning advantage over carbs, that is,Inputting the e.g.t. into the efi and tuning to match the pipe will broaden the peak rpm of the pipe. e.g. colder egt after peak , hotter egt before peak.
Thats what ignition advance if for
almost all twos stroke ignition curves do this to some degree.If you want to play with it yourself all you need is a programmable ignition unit, you dont have to have EFI to do that.
you wouldnt adjust the EGTs with fueling as it'd be a good way to sieze the motor, however you could simply have a function in the programing which alters fueling based on EGTs to keep her right on the money.
Ie: IF TPS>17mA AND EGT>1200F, increase injection pulse duration
Post by: jared31 on March 21, 2013, 12:30:09 PM
The two Injectors that you see inserted into the cylinder is what I Audit everyday at General Motors,We also make Injectors for The Harley Davidson line of Bikes.Awesome to see what You make being used in the sport you love.
Suitable bike to use, not cleaned from last ride!!
Injectors in place, still need to make the fuel rail. This will be connected to some head studs.
All the bits are starting to come together for the YZ250 EFI project.
Post by: vetman on March 21, 2013, 09:19:47 PM
Post by: Uniflow on March 23, 2013, 04:42:53 AM
Post by: Uniflow on March 23, 2013, 04:44:30 AM
Post by: Stusmoke on March 23, 2013, 04:48:03 AM
Should be working on the EFI systems but but decided to go to the Mihihi trail ride today with the EFI Bighorn. 40 K track, Bighorn did 39.5 ! Had a great time slugging it out with a 250F, hammer and tong ( more soft hammer and centerpunch ) He would get me out of the corners and into the corners but the bighorn was all over him on the open straighter bits. He was getting pissed off as he couldn't shake me and every time the track opened up I'd have him!! Great fun, you should have seen the look on his face when he was in front and looking to see where I was and what I was going to do next. Round the last corner and I had about 20 feet on him, would have won ( apparently you can't win a trail ride ), BUT the wire that handles all the current to everything broke and the mighty Bighorn stopped!! So the 250F beat me bugger. Haven't had so much fun in a long time. Walked back with tools, fixed it and rode it out so by rights it did finish. The wiring loom resembles more of a birds nest than anything, should spend some time tidying it up probably?
HAH! I guess his more "advanced" fooper didn't do him much good did it?
Post by: Uniflow on March 23, 2013, 05:17:49 AM
Post by: citabjockey on March 23, 2013, 05:56:53 AM
It's funny cause I would absolutely roost him on the hills, and that Bighorn can dig some terrain. I wouldn't hear him for a while, must have got sick of rocks getting thrown at him. One time the 250F was in front up a long hill and he tried to roost me. 250F can't roost it was funny it was a pathetic attempt. By rights he should have pasted me but I could see his suspension wasn't too good, he was all over the place, mind you so was I but I have a 1973 excuse. It's just that I'm so happy I've got that EFI Bighorn running so well now, It's too much engine for that frame and suspension.
Post by: Stusmoke on March 23, 2013, 08:13:12 AM
Post by: 2T Institute on March 23, 2013, 08:40:38 AM
I don't see a water gallery for water cooling the crankcases?
Post by: Uniflow on March 23, 2013, 08:08:08 PM
Post by: Uniflow on March 23, 2013, 08:19:53 PM
Post by: Uniflow on March 23, 2013, 08:32:09 PM
This frame is a DT / MX 360 frame not Kawasaki ( they were bad frames ). The engine compartment has been shortened 40mm with the swing arm lengthened 40mm. Engine is 40mm further forward. Forks are TZR 250 ( 39mm Dia ) units with race tec valves inside. Custom tripple clamps. Rear shocks are modified TT500 units. So for what it is the Bighorn handles ok. Rear shocks are still a little hard, as 2T pointed out I should change them. Biggest problems are weight and rider.
Post by: 2T Institute on March 23, 2013, 08:49:43 PM
http://www.igkoenigsklasse.de/index.php?option=com_marketplace&view=entry&catid=4%3Aparts&entry=2724%3Aaprilia-rsw-125-motorgehaeuse-magnesium&Itemid=100011
Post by: _X_ on March 23, 2013, 11:36:47 PM
Post by: Uniflow on March 23, 2013, 11:46:53 PM
Post by: 2T Institute on March 24, 2013, 01:07:56 AM
Post by: Stusmoke on March 24, 2013, 01:39:12 AM
This frame is a DT / MX 360 frame not Kawasaki ( they were bad frames ). The engine compartment has been shortened 40mm with the swing arm lengthened 40mm. Engine is 40mm further forward. Forks are TZR 250 ( 39mm Dia ) units with race tec valves inside. Custom tripple clamps. Rear shocks are modified TT500 units. So for what it is the Bighorn handles ok. Rear shocks are still a little hard, as 2T pointed out I should change them. Biggest problems are weight and rider.
When you say weight and rider do you mean the weight of the rider?
Whats a bighorns capacity anyhow?
Post by: Uniflow on March 24, 2013, 03:01:15 AM
Post by: Uniflow on March 24, 2013, 03:04:14 AM
Post by: Jeram on March 24, 2013, 04:35:51 AM
if so thats pretty sweet
An idea for you Neil,you should pop a 24/7 reedvalve on the reed cylinder that you making.
Would be very interesting to compare 24/7 valve to variable disc timing
looks fairly simple to make yeah?
Post by: riffraff on March 24, 2013, 05:40:54 AM
Post by: Stusmoke on March 24, 2013, 07:51:13 AM
Uni, you're starting to repeat yourself
Yeah first you're weighing in at 1/4 ton and now you're repeating yourself? You must really be getting on
Post by: 2T Institute on March 24, 2013, 08:12:25 AM
2T, ok you win, easy to change as my gearbox is a little further away from the crankshaft due to the intermediate gear / balance shaft ( engine runs backwards ). Just for you I'll change it.
whoever ever buys one will be the winner
Post by: Uniflow on March 24, 2013, 11:11:53 PM
rider, 110 Kg, full of fuel. About what I thought.
Post by: Stusmoke on March 24, 2013, 11:49:00 PM
There we go, weighed both, rider and bike. Bighorn at 121 Kg with about 1/4 tank of fuel.
rider, 110 Kg, full of fuel. About what I thought.
Thats not so bad. Poor little bighorn motor really is pulling almost a quarter of a ton. It sounds worse when you say it like that though.
Post by: _X_ on March 25, 2013, 12:52:54 AM
Post by: SachsGS on March 25, 2013, 02:39:47 AM
Post by: evo550 on March 25, 2013, 08:20:39 AM
back off the fat people you twiggies.Yeah!!!!
He might be fat, but you guys are ugly...and he can diet, but you can't fix ugly
Post by: 2T Institute on March 25, 2013, 09:02:49 AM
And when you try to fix ugly .....................back off the fat people you twiggies.Yeah!!!!
He might be fat, but you guys are ugly...and he can diet, but you can't fix ugly
Post by: Uniflow on March 25, 2013, 09:57:40 AM
Can you read this? Getting a little off track here, but this is the original sales brochure 1973 F9 bighorn, when they knew how to bull****, I mean advertise!!
Post by: evo550 on March 25, 2013, 11:24:18 AM
And when you try to fix ugly .....................back off the fat people you twiggies.Yeah!!!!
He might be fat, but you guys are ugly...and he can diet, but you can't fix ugly
.......Uuuummmm, I got nuthin'
Post by: 2T Institute on March 25, 2013, 12:05:46 PM
Post by: _X_ on March 25, 2013, 08:52:20 PM
Post by: cnrcpla on March 25, 2013, 09:58:59 PM
Post by: _X_ on March 25, 2013, 10:20:27 PM
Maybe she's allergic to bee's and got stung in the face way to many times? or he's a cross dresserHA!
Post by: scotty dog on March 25, 2013, 10:43:37 PM
hahahaa yes!back off the fat people you twiggies.Yeah!!!!
He might be fat, but you guys are ugly...and he can diet, but you can't fix ugly
Post by: Stusmoke on March 25, 2013, 10:53:23 PM
Can you read this? Getting a little off track here, but this is the original sales brochure 1973 F9 bighorn, when they knew how to bull****, I mean advertise!!
I can read it but 28 HP? How far engine tech has come in the last 40 odd years is BS. Same with computers. Except I've already preordered my preorder of a quantum computer...
Post by: Uniflow on March 25, 2013, 11:41:08 PM
Also says you can buy a factory "hot kit", 44 HP.
Post by: Jeram on March 26, 2013, 10:06:40 AM
I see on the original brochure that the F9 weighs 127 Kg.
Also says you can buy a factory "hot kit", 44 HP.
yeah the hot kit had the shorter ratio gearbox, a different piston (lighter and single ring, very rare these days) and Im sure a few other tricks like pipe and carb etc.
Post by: bearorso on March 26, 2013, 06:48:25 PM
The Arctic Cat functions as a DFI engine at low speeds, correct? I wonder how the Orbital patents are affecting all of this?
The old aircooled open class mx's ran a lot of piston clearance and you could hear the piston knock until things warmed up. I've got an old Yamaha 400 in the shop right now and it's pretty noisy when it first fires up. I'm pretty sure piston metallurgy has improved quite a bit since those old SC500's.
It's "DFI", all the time. Though it does more than just put fuel into the combustion chamber - it's all written there.
It's a "different animal" entirely from Orbitals system.. A low pressure ( see 58PSI) system that is injected at multiple points in the rotation of the crankshaft / piston positions.
And the oil injection - oh yeh!. Into the cases, and also into the fuel rail / injectors, through to the little end, and all metered and timed. The 'right' oil ratio, at the 'right time'. Hopefully.
As I've written all along - there are so many alternative paths to 'DFI' 2ts. Orbital's, really found their "home" in 4ts - they are paid royalties / have licensing agreements with a vast array vehicle manufacturers.
Orbital's is a complicated system, that requires very high pressures. And, does not take advantage of / stay true to the "simplicity of 2 Strokes". Well suited for a 4t Car / Truck engine though.........
Get something like a Quaife Gearbox, and run a primary chain / belt, or gears, and you've a gearbox. I bet my arse that you'll see blokes doing this. It will probably be a Pom. They're crazier than Aussies, or even those Demented Kiwis. And, they still have Very Easy MOT ( rego) stds. At least whilst they can fight off the European Parliament and their legislative minions.
It's the sort of thing I expect to see in Performance Bikes magazine. They regularly feature very trick 2 strokes.
As for the piston - lets see - SC500s - round about 1974, or thereabouts. I think piston / engine tech and materials have moved on just a bit, in all the subsequent decades. I used to watch Brian Clarkson Road Race his SC500, when I was a teenager - I haunted him in his tiny shop with the Rickman distributorship in Penrith in the 70s, then worked about 50 metres from his wreckers in the late 90s. A Gentleman and Right Royal Ratbag.
Post by: Uniflow on April 14, 2013, 03:47:35 AM
Just an update. The bike is back at Blackwood Yamaha ( today ) getting all the bits put back on. By rights it's ready to start! This time I'm running the ignition through the Link computer. This will take a little sorting out ( programing the timing ). Using a 450F flywheel and stator. See the drum throttle valve we cast earlier in this thread.
Post by: TMKIWI on April 14, 2013, 08:00:28 AM
Post by: 2T Institute on April 14, 2013, 09:03:21 AM
Post by: Jeram on April 14, 2013, 11:08:13 AM
Quick question, where is the oil injected? with the fuel or in the reed boot?
I only ask because I wonder what will happed to the reeds if the dont have an oil cushion?
Post by: metal_miracle on April 14, 2013, 03:04:42 PM
Post by: Lolerbabop on April 14, 2013, 05:08:08 PM
Post by: Jeram on April 15, 2013, 12:40:06 PM
Post by: Uniflow on May 03, 2013, 01:33:50 AM
Post by: Uniflow on May 03, 2013, 03:41:50 AM
Post by: Jeram on May 03, 2013, 05:56:19 AM
Video?
Post by: citabjockey on May 03, 2013, 04:00:31 PM
Audio?
LOL
One quick question on the setup. Could you have used a single injector -- just on one side? Seems to me like the fuel/air coming in from the transfers would get pretty mixed up in the combustion chamber as the piston does the compression thing. Might be an interesting experiment that could possibly simplify the system a touch. What electricity source are you using for the pump/computers? Does the 450F stator have enough juice for the setup? Are you running a battery?
nice work mate!
Video?
Post by: Jeram on May 04, 2013, 02:13:12 AM
Or better yet....[/quote]
Audio?
LOL
One quick question on the setup. Could you have used a single injector -- just on one side? Seems to me like the fuel/air coming in from the transfers would get pretty mixed up in the combustion chamber as the piston does the compression thing. Might be an interesting experiment that could possibly simplify the system a touch. What electricity source are you using for the pump/computers? Does the 450F stator have enough juice for the setup? Are you running a battery?
I dont recon youd start getting uneven combustion, as it really doesnt mix that much because the aim is to have a little turbulence as possible in the intake charge to limit mixing between the exhaust gas and fresh gases.
Post by: Uniflow on May 04, 2013, 02:26:09 AM
Post by: evo550 on May 04, 2013, 08:02:21 AM
Post by: Uniflow on May 04, 2013, 08:31:26 AM
Post by: evo550 on May 04, 2013, 10:22:23 AM
Post by: Blackwood Yamaha on May 06, 2013, 11:35:21 PM
Finely the external fuel pump has got here. I have spent a few hours getting it mounted and wired in but now we are ready for a proper run.
I have posted some more progress pictures on our facebook page. www.facebook.com/BlackwoodYamaha
Post by: citabjockey on May 07, 2013, 04:51:19 AM
Mind if I inline a interesting pic?
Post by: Blackwood Yamaha on May 07, 2013, 10:00:50 AM
Post by: Uniflow on May 12, 2013, 11:38:14 AM
Post by: 2T Institute on May 12, 2013, 11:51:20 AM
Be keen to see if you can nail the injector timing
Post by: evo550 on May 12, 2013, 12:14:03 PM
Post by: citabjockey on May 12, 2013, 02:49:24 PM
When you make adjustments on the computer is the link wireless?
You guys checking mixture with spark plug checks?
Do you have a cylinder head temp? EGT? Can you set mixture via that?
Thanks for posting this video!
Post by: 2T Institute on May 12, 2013, 03:07:56 PM
Is there any other 2t fuel injection systems (snowmobiles, outboards ect) that run premix through the injectors?
Modern sleds have dry bottom ends with sealed greased bearings and scant oil injection to the big ends, others with very low premix ratios. The premix is a non issue with oil in suspension and very high fuel pressure th oil will do what it's told.
Post by: Uniflow on May 12, 2013, 09:33:19 PM
. We still have a lot of options with what we have and this is what we will be playing with in the next while. With little runs like this including short full throttle squirts ( up the road ) the crank case seems oily on inspection but I want to set up the auto oiler before we go too much further, to be safe. I'm sick of having to walk out of trail rides ( early days of the Bighorn FI development ). It's a lot of fun to ride it certainly feels nicer down low speed than my standard YZ. This is the first time I've ridden it so I don't know about top end yet.Oil in the fuel is no problem, modern injectors love it.
Post by: TMKIWI on May 13, 2013, 07:45:28 AM
Good to see it running well so early.
You do realise what you have done, um can't be done according to experts in japan.
Post by: rlaj1004 on May 13, 2013, 01:09:58 PM
Post by: Uniflow on May 13, 2013, 08:58:01 PM
Post by: _X_ on May 13, 2013, 09:12:06 PM
Post by: Jeram on May 13, 2013, 10:46:37 PM
Would love to but at the moment the cost would be high. The Link computer cost $1500 NZD alone. Ultimately a computer board could be made to suit our application MUCH cheaper. At the moment we are just keen to prove this technology can work, In saying that if people are interested I will certainly consider making kits, but lets get some hours on this one first.
Wow I didnt realise the Link computer was that pricey.
If only you could get a little $250 netbook computer, install a program on it and then have the loom feed into the PC via a 9pin serial or USB
then zip tie the PC to the airbox hahaha
Post by: Uniflow on May 13, 2013, 10:55:24 PM
Post by: Jeram on May 14, 2013, 07:50:28 AM
Something like that is getting more and more possible these days.
i wonder if anyones been smart enough to create an adroid or iphone app?
you can plug your harley davidson into an iphone and run the tacho through the phone screen, so wouldnt be much harder to install software to control injectors
Post by: citabjockey on May 14, 2013, 03:35:53 PM
That said I am sure the components on that link computer are pretty darn cheap on their own and fabbing a special purpose board is not that pricy. Its the software NRE that costs the vendor plenty. If enough units are sold then its easy for the price of the whole shebang to come down. But any manufacturer building a bike that gets into mass production is probably going to end up building their own system so development systems like this link are not cost effective either -- and stay that way.
Uniflow -- for your system, how many inputs and outputs are you using? Ambient temp and pressure? O2? throttle position? Rpm (and/or crank position)? Cylinder temp? exhaust temp? Are the only outputs for the injectors? Is there another for the fuel pump? Other outputs? And the link to your laptop -- that is USB? I still think having a WiFi or bluetooth connection with be way cool. Never even bother with a cable connection.
Post by: eprovenzano on May 14, 2013, 05:25:24 PM
I still think having a WiFi or bluetooth connection with be way cool. Never even bother with a cable connection.
I can see it now... citabjockey sitting in his big comfortable shaded outdoor chair, an umbrella drink in the cup holder, tapping away on his laptop... and just screwing with the guys on the track.... And the hole time having a big ****ty grin on his face....
Post by: citabjockey on May 14, 2013, 07:26:08 PM
Lesee, lets give Villo a nice top end cut out. Yes, that's perfect , no power above 5000 rpm.
Ok, here comes Milsaps, Uh Oh -- his mixture is going so lean his $1500 header is glowing red, he he he. Like watching a volcano ready to blow!
Chad Reed has so much fuel now he has flames coming from the silencer! Too bad the bike will not clear the small doubles anymore!
And now JS7 is in the whoops, what now? Nevermind.
Have fun guys!
LOL
I still think having a WiFi or bluetooth connection with be way cool. Never even bother with a cable connection.
I can see it now... citabjockey sitting in his big comfortable shaded outdoor chair, an umbrella drink in the cup holder, tapping away on his laptop... and just screwing with the guys on the track.... And the hole time having a big ****ty grin on his face....
Post by: eprovenzano on May 14, 2013, 07:49:46 PM
Post by: Uniflow on May 14, 2013, 09:30:40 PM
Probably not possible to have a phone app run injectors. Uniflow will correct me if I am wrong but that requires an operating system that specializes in "real time" operations. There needs to be a very direct connection -- with no delay -- between what the CPU wants and the device being controlled as well as in the other direction from the sensors to the CPU. With windows,linux,android etc OS there are many layers that let the computer do many things at once but none of them with real time response. Humans are slow enough that we don't notice it but an injector sure would.
That said I am sure the components on that link computer are pretty darn cheap on their own and fabbing a special purpose board is not that pricy. Its the software NRE that costs the vendor plenty. If enough units are sold then its easy for the price of the whole shebang to come down. But any manufacturer building a bike that gets into mass production is probably going to end up building their own system so development systems like this link are not cost effective either -- and stay that way.
Uniflow -- for your system, how many inputs and outputs are you using? Ambient temp and pressure? O2? throttle position? Rpm (and/or crank position)? Cylinder temp? exhaust temp? Are the only outputs for the injectors? Is there another for the fuel pump? Other outputs? And the link to your laptop -- that is USB? I still think having a WiFi or bluetooth connection with be way cool. Never even bother with a cable connection.
The Link is a versatile little unit. As well as running the injectors we have outputs for many other operations, power valve, pulse oil metering pump, more injectors timed differently if needed, shift light, cooling fan, fuel pump drive lots of stuff. We are only using one injector drive ( although that may change) and the fuel pump drive, also might add the oil pump drive. The fuel pump drive only turns the pump on when the engine is turning over so when you stop, the pump stops. You can also have up to three overlay maps running at the same time for real fine tuning, or injection start point changes. All good useful stuff.
Inputs at the moment are TPS, rpm, crank angle sensor, engine coolant, ambient pressure and chamber pressure drives the fuel regulator. I did also set up a sampling valve to the crankcase, a small valve wired to the injector drive so the computer was only able to "see" the pressure in the crankcase as the injectors fired not all the other pressures. I don't want to put anything in the exhaust that will affect the way it runs, no sensors that will protrude in. We might have the system too simple? but it seems to go alright. I'm freshening up my YZ, new piston kit, new pipe ( same as the EFI bike ) so we can get a good comparison.
Post by: Kodackamera on May 14, 2013, 10:43:02 PM
This project is really inspirational, clever work!
Post by: Jeram on May 15, 2013, 05:55:44 AM
Probably not possible to have a phone app run injectors. Uniflow will correct me if I am wrong but that requires an operating system that specializes in "real time" operations. There needs to be a very direct connection -- with no delay -- between what the CPU wants and the device being controlled as well as in the other direction from the sensors to the CPU. With windows,linux,android etc OS there are many layers that let the computer do many things at once but none of them with real time response. Humans are slow enough that we don't notice it but an injector sure would.
That said I am sure the components on that link computer are pretty darn cheap on their own and fabbing a special purpose board is not that pricy. Its the software NRE that costs the vendor plenty. If enough units are sold then its easy for the price of the whole shebang to come down. But any manufacturer building a bike that gets into mass production is probably going to end up building their own system so development systems like this link are not cost effective either -- and stay that way.
Uniflow -- for your system, how many inputs and outputs are you using? Ambient temp and pressure? O2? throttle position? Rpm (and/or crank position)? Cylinder temp? exhaust temp? Are the only outputs for the injectors? Is there another for the fuel pump? Other outputs? And the link to your laptop -- that is USB? I still think having a WiFi or bluetooth connection with be way cool. Never even bother with a cable connection.
The Link is a versatile little unit. As well as running the injectors we have outputs for many other operations, power valve, pulse oil metering pump, more injectors timed differently if needed, shift light, cooling fan, fuel pump drive lots of stuff. We are only using one injector drive ( although that may change) and the fuel pump drive, also might add the oil pump drive. The fuel pump drive only turns the pump on when the engine is turning over so when you stop, the pump stops. You can also have up to three overlay maps running at the same time for real fine tuning, or injection start point changes. All good useful stuff.
Inputs at the moment are TPS, rpm, engine coolant, ambient pressure and chamber pressure drives the fuel regulator. I did also set up a sampling valve to the crankcase, a small valve wired to the injector drive so the computer was only able to "see" the pressure in the crankcase as the injectors fired not all the other pressures. I don't want to put anything in the exhaust that will affect the way it runs, no sensors that will protrude in. We might have the system too simple? but it seems to go alright. I'm freshening up my YZ, new piston kit, new pipe ( same as the EFI bike ) so we can get a good comparison.
sounds like your link computer would be able to handle a servo controlled 24/7 reed inlet valve
would make it just as quick as a disc valve motor!
Post by: 2T Institute on May 15, 2013, 07:42:37 AM
Post by: Uniflow on May 15, 2013, 10:13:52 AM
Post by: 2T Institute on May 15, 2013, 11:12:43 AM
Post by: eprovenzano on May 15, 2013, 02:31:45 PM
Is that going to be part of the EFI marketing plan??? I can see it now... If you purchase this EFI system, we can add for the low low price of only $29.95, this personalized Uniflow riding gear.... This riding gear can be purchased separately for low price of $159.95, but if you order an EFI system now, it can be included for the low price of only $29.95. At least you put a helmet on...
Post by: Uniflow on May 15, 2013, 08:28:37 PM
very seriously. Next time I'll use a clean tee shirt! We know our marketing
Post by: TMKIWI on May 16, 2013, 08:13:33 AM
Maybe you should go for the swandri and red band look.
Post by: Uniflow on May 16, 2013, 08:37:01 AM
Post by: TMKIWI on May 16, 2013, 09:33:29 AM
No, that's winter attire. When are you coming up to have a ride on the YZ TM? You might have to swap for a go on your 300.
Count me in. Name a time and I'll see whats on.
Your more then welcome to thrash the TM.
Post by: overrevn on May 18, 2013, 05:19:38 AM
Post by: Uniflow on May 19, 2013, 09:12:14 AM
No claims on HP until we see a dyno.
Post by: SachsGS on May 19, 2013, 02:41:27 PM
Post by: Uniflow on May 19, 2013, 08:12:46 PM
Post by: TMKIWI on June 05, 2013, 10:13:48 AM
Post by: eprovenzano on June 05, 2013, 12:49:38 PM
Hows the bike going Neil.?Inquiring minds want to know....
Post by: Uniflow on June 09, 2013, 07:42:04 AM
I know this is not what you want to hear, more excuses, the YZ 250 EFI is running well, but we have not had a decent chance to get video. Weather has been bad or finally got sorted for this Saturday's Epic Events trail ride in Taupo , Owner ( Wayne of Blackwood Yamaha ) has just been too busy selling bikes and couldn't make it on Saturday and Sunday pissed down again! We have had a fuel pump bugger up ( made in china ) that slowed us down for a while until it was realized what had happened. New computer has not arrived yet ( the one that costs less that half the Link ) so haven't had a chance to look at that yet. But we have discovered that the Link can vary the end of injection timing, through an overlay table, so we are working though this now.
I did attend the Saturday ride with the F9 ( and the new injection timing software ) and proceeded to tune it into a rocket. I have looked at putting this engine in a modern frame but it's just too big and would need a frame change and I'm not willing to do this to my alloy 250F frame. Work is still proceeding with the YZ360 cases ( to fit the 250F frame ) but it is slow. Too much fun riding the F9 in the weekends.
Post by: Uniflow on June 10, 2013, 01:12:09 AM
This Epic Events ride was a lot of fun.
Thanks Dave for the photos.
Post by: Z50Jay on June 16, 2013, 04:02:41 AM
Post by: Marco810 on June 18, 2013, 01:58:44 PM
Post by: CCOADY454 on June 18, 2013, 02:45:59 PM
The other in the YZ250F frame with my own 360 engine,Similar to Husqvarna 360 engine by chance?
Post by: TotalNZ on June 18, 2013, 07:50:53 PM
Not similar to any dirtbike 2t motor i've ever seen. There are pics and more info in another thread.The other in the YZ250F frame with my own 360 engine,Similar to Husqvarna 360 engine by chance?
Post by: cnrcpla on June 19, 2013, 12:35:52 AM
Post by: Uniflow on June 19, 2013, 04:31:42 AM
Yes, I'm concentrating on getting this NEW 360 engine finished. This is not a production engine, it's a one off to test all the bit's of technology I've developed from the F9, EFI YZ250 and a few other engines I've worked with. IF all goes well I would produce them for others, but they won't be cheap!
Lets concentrate on getting this first one up and running. Patterns are heading off to the foundry Monday so might have some heat treated case castings to look at by the end of next week.
Post by: Lolerbabop on June 20, 2013, 09:35:27 PM
Post by: Uniflow on June 24, 2013, 09:22:59 AM
First dyno run on the YZ 250 EFI.
Post by: factoryX on June 24, 2013, 09:37:40 AM
Post by: TMKIWI on June 24, 2013, 09:43:27 AM
Sound like it could pull abit more.
Post by: Uniflow on June 24, 2013, 09:46:52 AM
Post by: bearorso on June 24, 2013, 11:02:55 AM
I'd very much like to see the injector set up, from inside.
Looking at it positioned in the first transfer 'ducts', one could think it's just injecting into that, but, of course, you could have it with a long feeder deeper into the cases, or going to the boost ports, or, well, anybloodywhere.
And, of course, you have every right to keep it to yourself.
At first, I imediately thought of the Bimota 500 debacle, with transfer port injectors. But, that was 15 / 16? years ago, rushed into production, and I'd say Any software / hardware has gone through more than few generations of development.
I know you've got a lot on with this, and you're doing a brilliant job ( Bloody Kiwis
), but have you, are you giving thought to a third injector, in an 'in manifold' position? Or, in a "in side of barrel", projecting up to the combustion chamber, as in the Athena and the secondary Ossa Injectors. Ossa have said that to get the power they want for the Enduro / MX version of their rearward sloper, they are going to at least 3 injectors.As I said, this is brilliant stuff, it's fantastic to see a 'Do-er', doing.
Post by: TotalNZ on June 25, 2013, 08:07:39 AM
Post by: Uniflow on June 25, 2013, 09:06:15 PM
Post by: bearorso on June 26, 2013, 09:28:26 AM
It's just curiosity - I'm not having a go at you for being secretive - though you'd have Every right to be so. You've enough on your hands, and have shown an enormous amount of your work.
When I see the injectors into the rearward of the transfers (3? - I don't know the configuration. of the YZ barrel, just thinking of the most common transfer set up) I think of the shrouding that it might create if the transfer splitters are there still (goodness only knows) as std, or if a long extension of the injector is used to get the charge point out of the one transfer, into the crank / lower case area, thence it doing the 'usual' routing of the charge. Then thinking perhaps, you are locating the main charge in the rear transfers, using that shrouding, to have the forward transfers predominantly as an 'air' charge to block the fuel charge from exiting the exhaust, like a version of AST.
Yep, my imagination can go wild.................
Cripes, you're brave if you are going to try to run with no premix (re oil metering), although I think you are doing the oil metering to the mains / big end (little end?) Then using a Very Lean premix to lubricate the piston /rings / barrel (little end?)
?Just rapt at your efforts, fascinated by what you're doing, yourself. Not getting others to do things for you, and just doing a Cad Drawing and dimensions. A Doer, as I said.
Geez I Hate praising Kiwis, they're a 'Orrible mob of bastards...................
somethings gone 'wrong' with me, I'm finding that funny little comedienne, Cal Wilson, quite attractive, nowadays............ I'll be deported soon, for being too tolerant / fond of Un Zudders.
Post by: Uniflow on July 12, 2013, 04:57:53 AM
Post by: TMKIWI on July 12, 2013, 05:24:16 AM
Post by: Uniflow on July 12, 2013, 05:59:48 AM
This is feed back from someone ( old ) that rides a normal YZ all the time ( and F9 ) so I'm just relaying what the EFI felt like to me to ride. There has been no adjustments from where you saw it on the dyno, still too rich up top.
If you like " rip, **** and bust" you will not like the EFI, it is more like a YZ250F but with more power! Smooth power delivery all over. If I wanted to win enduros I'd use this bike. Top end both, bikes are similar ( remember the EFI has still not been dyno tuned so there is more power to be had yet ).
You knew I was going to say this but, I like it.
There is video but I was in control of that and it seems half the time the camera was pointing up my nose, plus lots of mud, so we will see if there is anything to post when we down load it.
Post by: Stusmoke on July 12, 2013, 06:16:28 AM
I couldn't help it, just wanted to see who was watching.
This is feed back from someone ( old ) that rides a normal YZ all the time ( and F9 ) so I'm just relaying what the EFI felt like to me to ride. There has been no adjustments from where you saw it on the dyno, still too rich up top.
If you like " rip, **** and bust" you will not like the EFI, it is more like a YZ250F but with more power! Smooth power delivery all over. If I wanted to win enduros I'd use this bike. Top end both, bikes are similar ( remember the EFI has still not been dyno tuned so there is more power to be had yet ).
You knew I was going to say this but, I like it.
There is video but I was in control of that and it seems half the time the camera was pointing up my nose, plus lots of mud, so we will see if there is anything to post when we down load it.
My biggest concern is the weight of it, so lets hear it from a working, feasible EFI unit on the YZ250, just how much more does it weigh? Yeah yaeh I know that I can't feel two kilos on the stand, but I can feel it when I divebomb the inside line. The 250SX is already at 216 pounds. In 2011, Prior to KTM giving in to the public demanding something they didn't really understand (PDS linkage), it weighed 212 pounds. Add on whatever EFI ends up being and it adds up. Four stonks get loaded up with all the bells and whistles, making them bloated and fat, two strokes shouldn't.
Post by: Uniflow on July 12, 2013, 08:10:54 AM
Post by: Stusmoke on July 12, 2013, 09:28:24 AM
Weight? Throttle body is lighter than a carb but add fuel pump, small battery ( could be a capacitor ) and link unit. Flywheel and stator approx same weight, plus a little wiring. You are looking at around a Kg and a half extra. You won't notice it. Cost is still the big problem.
That, is something I would be well and truly happy with.
When you say it feels like an uber powerful 250F, do you mean it literally? Does it feel mellow and soft, does it feel slower revving, has its "crackability" gone? If so, I'd definitely be after some measure of customization. While an uber powerful 250F powerband on the 250 would be the ducks nuts for hardpacked, flat/offcambered tracks, I'd like some snap back in soft and tight stuff.
Post by: Stusmoke on July 12, 2013, 09:58:16 AM
Ahem. How narrow are the spray nozzles? If you left your YZ sitting for a while with say 50:1 premix, wouldn't there be potential for a blockage in the injectors? To be clear, that was an actual question, I really have no idea what I'm talking about.Do you still use the application of air pressure changes to draw fuel/airmixtures into the cylinder during the combustion cycle? If so does that free up the crankcases for a sump arrangement?
Again, I'm not disputing anything, I'm just trying to learn.
Post by: GerbilGronk on July 12, 2013, 11:13:25 AM
The video may have to wait until next time due to technical deficincies and mud.
http://s854.photobucket.com/user/GerbilGronk/library/Random%20Shots
http://s854.photobucket.com/user/GerbilGronk/media/Random%20Shots/IMG_8928_zpsfe2f88c5.jpg.html
http://s854.photobucket.com/user/GerbilGronk/media/Random%20Shots/IMG_8927_zps94d576b6.jpg.html
http://s854.photobucket.com/user/GerbilGronk/media/Random%20Shots/IMG_8925_zps96ba0e7c.jpg.html
http://s854.photobucket.com/user/GerbilGronk/media/Random%20Shots/IMG_8924_zpsb83289f1.jpg.html
Post by: HCE on July 12, 2013, 01:42:58 PM
Post by: Stusmoke on July 12, 2013, 10:28:15 PM
Very cool. Who makes the pipe guard on the YZ?
x2 it looks pretty serious. And what the hell was the massive piece of melted gunk?
Post by: Uniflow on July 12, 2013, 10:37:35 PM
It's still early days in understanding what we have got, it would seem that the injection timing has a big influence on the way the power is delivered, bottom, mid range. I think from what we have found so far that the power curve can be manipulated at this lower middle range with still the same top end. Yesterday it seemed the "power band" as such was gone!
I think the bit of metal in the last picture was from a casting disaster some years back, I'm not sure how that got in there.
Post by: Uniflow on July 12, 2013, 10:46:57 PM
Post by: Stusmoke on July 12, 2013, 10:49:50 PM
Stu, put it this way, the EFI bike was by far the best bike for the conditions yesterday.
It's still early days in understanding what we have got, it would seem that the injection timing has a big influence on the way the power is delivered, bottom, mid range. I think from what we have found so far that the power curve can be manipulated at this lower middle range with still the same top end. Yesterday it seemed the "power band" as such was gone!
I think the bit of metal in the last picture was from a casting disaster some years back, I'm not sure how that got in there.
Really? I thought it might have been the remains of a 250F silencer after 10 minutes of idling
Very cool what you've done here mate. On the off chance I'm wrong and the big four truly believe that four strokes will continue to rule motocross forever and the sport will never change back to two strokes and they DON'T all have their designs working perfectly and locked up in company vaults, I know who I'd be calling if I was Yamahas two stroke R&D department.
Post by: Uniflow on July 12, 2013, 11:26:27 PM
I think manufactures still have a **** load of valves to sell yet.
Post by: TMKIWI on July 13, 2013, 12:10:16 AM
I bet the track was interesting. It has been raining here for 5 days now and I am over it.
Post by: Uniflow on July 13, 2013, 12:32:47 AM
. After yesterday I'm more than happy for anyone to ride it, with Wayne's permission, I've been a bit nervous as to how it might perform in the real world. Yes a bit muddy but central plateau drains well so still plenty of grip. TM, do you do any of the Epic Events rides? Be happy to meet you at the next event with a view to do a " bike test ". If you give it a bad review you will have to ride the Kawasaki for the rest of the day and I invite you to review that
Post by: Stusmoke on July 13, 2013, 01:09:05 AM
Post by: TMKIWI on July 13, 2013, 02:26:32 AM
Will let you know when I do the next one.
I doubt I would give the bike a bad reveiw, but I can be persuaded with beer to give an excellent one.
You can thrash the TM as much as you want as well.
Post by: GerbilGronk on July 13, 2013, 09:35:14 AM
Heaps of two strokes as people see the light and the only bike I saw getting a tow in was a four stroke.
Post by: Stusmoke on July 13, 2013, 09:56:41 AM
This project was undertaken as " non profit " , a hobby, because I would like an EFI twostroke myself but no one offer an EFI bike. I waited for the OSSA, but noting seem's to be happening there so I decided to have a go myself and so far so good. I would be happy if Yamaha started to produce an EFI towstroke. Perhaps like this one or perhaps DI either way it would be a good thing, until this happens I'll continue on experimenting with what we have ( and with a bit of spare time perhaps finish the new 360 )!
I think manufactures still have a **** load of valves to sell yet.
And look what you've managed to produce in your spare time as a hobby! Imagine what Yamaha or Honda could accomplish if they threw their engineering department and half a billion dollars at it! Honda made good two strokes, whether they admit it or not.
Post by: bearorso on July 13, 2013, 03:53:32 PM
Imagine what Yamaha or Honda could accomplish if they threw their engineering department and half a billion dollars at it! Honda made good two strokes, whether they admit it or not.
The thing is, 1/2 a billion is not needed. Not even 1/2 a million would be needed for development. As I feel it's just sitting there, gathering dust, in quite a few company archives. Of course, you've then got tooling up / manufacture costs, but strict development costs, from right now .....
Yamaha have their DFI sorted in their Outboards - it, as it stands, may, or may not be suitable for bike use. Honda, you can guarrantee, have every damned aspect of 2ts sorted - and probably from a lot longer than decade and a half ago. Just their AR tech, could have been applied to real performance applications , and not just the Asian (and later, at a tiny scale, Australian ) trail bike / dual sport market. AR, with an electronic carb (EFI) - since it's got so cheap it's now on Postie Bikes (saw the new ones the other day - Wot, they are Green and White, not Racing Red?
It's just not right, I telz Yuz ) - would probably pass "whatever" these bloody Euro 3 specs are, whenever (2017) they bloody well 'have' to be met ...........No, Honda = All Four Strokes, All The Time. Therefore, Honda, can well and truly, go **** themselves.
Post by: Stusmoke on July 13, 2013, 10:35:11 PM
Imagine what Yamaha or Honda could accomplish if they threw their engineering department and half a billion dollars at it! Honda made good two strokes, whether they admit it or not.
The thing is, 1/2 a billion is not needed. Not even 1/2 a million would be needed for development. As I feel it's just sitting there, gathering dust, in quite a few company archives. Of course, you've then got tooling up / manufacture costs, but strict development costs, from right now .....
Yamaha have their DFI sorted in their Outboards - it, as it stands, may, or may not be suitable for bike use. Honda, you can guarrantee, have every damned aspect of 2ts sorted - and probably from a lot longer than decade and a half ago. Just their AR tech, could have been applied to real performance applications , and not just the Asian (and later, at a tiny scale, Australian ) trail bike / dual sport market. AR, with an electronic carb (EFI) - since it's got so cheap it's now on Postie Bikes (saw the new ones the other day - Wot, they are Green and White, not Racing Red?
No, Honda = All Four Strokes, All The Time. Therefore, Honda, can well and truly, go **** themselves.
Well said. And I have to wonder just how much more beneficial this all four stroke all the time thing is working out for the big four. For gods sake Yamaha doesn't even field a factory effort anymore! Last time I heard anyway. Yamaha had the motocross market in the palm of their hand once upon a time with their old school YZs. Sales have plummeted too. They might make alot more off of four stroke parts than two stroke parts, but has it really balanced it out? I guess it must have otherwise they would stop and rewind.
Post by: TMKIWI on July 14, 2013, 07:36:16 AM
Jumping on the green band wagon was very easy for them to do and now the hole they have dug is rather large.
Post by: bearorso on July 14, 2013, 08:11:27 AM
The Japs are a very proud people and will not admit that maybe they got it wrong.
Jumping on the green band wagon was very easy for them to do and now the hole they have dug is rather large.
You're not wrong there, on both points.
I still have a bit of , faith in Yamaha - they at least have kept producing, and supplying to most world markets, 2t MXers. I live in hope, that the company that put reed valves and good porting into their production 2ts, of all types, over 40 years ago, then the single shock, and so many other things - including having the balls to mass produce 4ts that were not Foo Foo bikes, will be the first Japanese manufacturer to give us a modern 2t.
Post by: Stusmoke on July 14, 2013, 08:12:47 AM
The Japs are a very proud people and will not admit that maybe they got it wrong.
Jumping on the green band wagon was very easy for them to do and now the hole they have dug is rather large.
You're not wrong there, on both points.
I still have a bit of , faith in Yamaha - they at least have kept producing, and supplying to most world markets, 2t MXers. I live in hope, that the company that put reed valves and good porting into their production 2ts, of all types, over 40 years ago, then the single shock, and so many other things - including having the balls to mass produce 4ts that were not Foo Foo bikes, will be the first Japanese manufacturer to give us a modern 2t.
x2. And Sushi kicks arse when its fresh.
Post by: TMKIWI on July 14, 2013, 08:24:29 AM
.
I still have a bit of , faith in Yamaha - they at least have kept producing, and supplying to most world markets, 2t MXers. I live in hope, that the company that put reed valves and good porting into their production 2ts, of all types, over 40 years ago, then the single shock, and so many other things - including having the balls to mass produce 4ts that were not Foo Foo bikes, will be the first Japanese manufacturer to give us a modern 2t.
You may be right. My local Yamaha dealer told me the other day that Yamaha was bringing out a EFI YZ250 for 2015.
Who knows if it an internet rumor or not. Would be nice to see it happen.
Post by: bearorso on July 14, 2013, 08:57:41 AM
.
I still have a bit of , faith in Yamaha - they at least have kept producing, and supplying to most world markets, 2t MXers. I live in hope, that the company that put reed valves and good porting into their production 2ts, of all types, over 40 years ago, then the single shock, and so many other things - including having the balls to mass produce 4ts that were not Foo Foo bikes, will be the first Japanese manufacturer to give us a modern 2t.
You may be right. My local Yamaha dealer told me the other day that Yamaha was bringing out a EFI YZ250 for 2015.
Who knows if it an internet rumor or not. Would be nice to see it happen.
Just give thought to the sort of sales Yamaha would get from such a bike. Just for a moment, cogitate on it........
They've made serious profits on the current alloy framed 125s and 250s, with the prices they've charged. They've 'milked' them for all they're worth, for many years now. If they didn't "go the gouge" on 'EFI / DFI / whatever the bloody things turn out to be', New 2ts, They'd sell a Lot of bikes. And that's what you'd think they'd want, in these straightened times for bike sales.
Hmmm, I wonder if they'd apply the reverse cylinder idea to such a "dream bike"? It would be logical, with their 4t MXers having gone that way. I, personally, think it's a very good set up (too many Drongos have equated JS's record on the reverse 450 as it being his "problem" - well, I guess the RMZ is a "POS", too?), that would enable so many benefits to 2ts. Tiny little Ossa, showed a great template for future 2ts. Just getting the pipe out of most harms way, would be a great thing.
Post by: Uniflow on July 14, 2013, 09:18:26 AM
Post by: bearorso on July 14, 2013, 10:20:00 AM
If you , Uniflow, can do a EFI 2t - that is far more sophisticated than just the placement of an 'electronic carburettor', which is so prevalent now, as to be of little expense, it's not much of an ask, for a major manufacturer to put such basic tech (I emphasize the 'electronic carb, that EFI basically is - not your impressive transfer port / case injection efforts) on a 2t.
Frankly, I think the Biggest Risk for manufacturers, is to not make a return, at least partially, to 2 Stroke production.
Rotary Debacle? With relation to bikes, Suzuki's RE5, Yamaha's never produced Rotary ( and their never produced, road going inline , pistoned Four cylinder 2t that the TZ 700 /750 were supposed to be 'race versions of, for the F750 class) Van Veen's OCR(?), Hercules / Sachs , Nortons (great track record, for such small operations, in both Race teams) Rotaries, were not debacle, just a branch of motorcycle engines, that was barely touched on. I know bugger all about the car market, but I don't recall lots of manufacturers, going for Rotaries, and losing their shirts over them?
But, I may have easily missed such a 'debacle' - as I said, I'm not particularly car orientated. Two Wheels have always been my passion - 4 or more, transportation, is all.
It's funny, my little suburb against the mountain, seems to have a bit of a RE(?) 8 cult going - I know of at least 9 of them being nearby
......... I love how my two V8 worshiping / Drag Racing brothers nearly foam at the mouth at the sound ( or even sight) of them!
Post by: Stusmoke on July 14, 2013, 10:29:41 AM
.
I still have a bit of , faith in Yamaha - they at least have kept producing, and supplying to most world markets, 2t MXers. I live in hope, that the company that put reed valves and good porting into their production 2ts, of all types, over 40 years ago, then the single shock, and so many other things - including having the balls to mass produce 4ts that were not Foo Foo bikes, will be the first Japanese manufacturer to give us a modern 2t.
You may be right. My local Yamaha dealer told me the other day that Yamaha was bringing out a EFI YZ250 for 2015.
Who knows if it an internet rumor or not. Would be nice to see it happen.
Just give thought to the sort of sales Yamaha would get from such a bike. Just for a moment, cogitate on it........
They've made serious profits on the current alloy framed 125s and 250s, with the prices they've charged. They've 'milked' them for all they're worth, for many years now. If they didn't "go the gouge" on 'EFI / DFI / whatever the bloody things turn out to be', New 2ts, They'd sell a Lot of bikes. And that's what you'd think they'd want, in these straightened times for bike sales.
Hmmm, I wonder if they'd apply the reverse cylinder idea to such a "dream bike"? It would be logical, with their 4t MXers having gone that way. I, personally, think it's a very good set up (too many Drongos have equated JS's record on the reverse 450 as it being his "problem" - well, I guess the RMZ is a "POS", too?), that would enable so many benefits to 2ts. Tiny little Ossa, showed a great template for future 2ts. Just getting the pipe out of most harms way, would be a great thing.
Absolutely. Think about how many Loyal (And ecstatic) customers of there are of the current "outdated" YZ250/125. Its one of the best motocross bikes every made. Imagine how many of those customers would line up for an updated YZ250/125 off the production floor, E/DFI or not.
The reverse cylinder idea was and still is a good one. The YZ450F of 2010-2013 (possibly 2014 yet, who knows) was a good, reliable bike that had issues. Name me a motorcycle that DOESN'T have issues. Oh yeah, the YZ250 and SX250.... OOps
Seriously though, it was VERY wrong of James AND his mechanical crew to be slinging **** at the YZF. He broke his contract to get away from it, thats all that needed to be said. Going on radio and dissing out your previous employer at his level of racing is just plain wrong IMHO. And as bearoso said, hes still just as ****ty if not worse on the best turning bike in the biz.
Post by: Nath88 on July 21, 2013, 02:19:36 AM
I'm looking at doing a similar thing with my registered 02 YZ250 motard, primary injector in the transfer for idle and light load, secondary in the throttle body to keep the crankcase cool. What oil pump are you using? I've been looking for a small one for a while, I even designed one for a final year engineering project, but wasn't very successful. Oil pump would be awesome on the street, stock tank gives me about 100km range
Post by: Stusmoke on July 21, 2013, 03:08:46 AM
Awesome project Uniquip!
I'm looking at doing a similar thing with my registered 02 YZ250 motard, primary injector in the transfer for idle and light load, secondary in the throttle body to keep the crankcase cool. What oil pump are you using? I've been looking for a small one for a while, I even designed one for a final year engineering project, but wasn't very successful. Oil pump would be awesome on the street, stock tank gives me about 100km range
Good to have another expert on here, welcome aboard! To be clear, I wasn't calling myself an expert.
Post by: Uniflow on July 21, 2013, 07:56:00 AM
Post by: Stusmoke on July 21, 2013, 08:03:54 AM
The YZ is using a small jet into the intake stream just behind the throttle body. It's programed to only open after 60% throttle. Works well. Although I'm designing a smaller electric ( UCU ) driven pump, smaller than a match box for accurate oiling, this will be feed straight to the bigend.
Does that mean it will be "four strokeized"? As in a sump to lube big end/Mbearings, and an oil spray to lube top end? Does that mean that the vaccum operation of the two stroke will be completely throw out the window in favour of a fuel pump? Seems a shame, its such a good idea.
Post by: Uniflow on July 21, 2013, 08:32:31 AM
Post by: TMKIWI on July 21, 2013, 08:45:20 AM
Main bearings are easily sealed off from the crank case and can run in there own oil bath.
So you wont be running a total loss system then. Or a bit of both.?
Post by: Uniflow on July 21, 2013, 09:14:20 AM
Post by: Stusmoke on July 21, 2013, 09:41:19 AM
No unfortunately, it will be a bit of both but overall should be less oil heading out the exhaust.
I call that a win then. So when you say oil that would normally be run through premix is pushed straight into the bigend and air, do you mean an oil jet spraying into the crankcases and onto the big end? If so, does that mean dropping premix entirely?
Post by: Nath88 on July 21, 2013, 11:57:07 PM
The YZ is using a small jet into the intake stream just behind the throttle body. It's programed to only open after 60% throttle. Works well. Although I'm designing a smaller electric ( UCU ) driven pump, smaller than a match box for accurate oiling, this will be feed straight to the bigend.
Clever, I've been looking at the Aprilia oil pulse pump 8222708 from the '00-'04 SR50 Ditech and '04-'08 SR50 Ditech Factory, pretty much fits your description. $126 new from AF1 Racing. Pulse from ecu based on load and rpm should be perfect.
The flow rate should be enough to supply the 250, it's capable of much more than the 50 requires to allow rapid bleeding of the oil lines. Would have liked to have found this before designing an oil pump, could have done my project on the actual injection system which would have been a lot more rewarding.
So you intend to plumb directly to the big end feed holes in the crankcase and let it disperse into the top end from the crank spinning? I'm imagining some little brass feed tubes from around the reed cage area then into the feed holes, but I'd be concerned about them breaking off with vibration, maybe some silicone hose might be appropriate. How will the pressure pulses in the crankcase affect the pump?
Post by: citabjockey on July 22, 2013, 12:43:54 AM
So if you put the main bearings "outside" the seals (then is the ignition in an oil bath?) then have a trench in the case and a corresponding hole in the crankshaft so the pump can feel oil into the crank. Then it can make its way to the big end bearing. Would there also be a need to supply oil to the wrist pin bearing? I wonder how SkiDoo does this?
Of course this whole setup could also supply main bearings if left inside of the seals.
Post by: Uniflow on July 22, 2013, 04:18:28 AM
. What was I thinking! I had it in my head to use a small brass tube sticking out of the crank case wall, just missing the bigend as it came around so any oil dribble off the end of this brass tube had no choice but get taken in by the passing bigend slot.
The Kawasaki does not need this as everything seems to be coated in oil inside the crank case, 55 hours now, still no problems bigend or otherwise.
The new engine ( 360 ) will need to be more sophisticated, perhaps using one of the systems above as it will be injecting into the cylinder.
Post by: Uniflow on July 24, 2013, 09:09:23 PM
Post by: _X_ on July 24, 2013, 09:34:40 PM
Post by: Uniflow on August 11, 2013, 09:23:30 PM
Video is being edited now, just the best bits, I told Dave to edit out the crashes and low speed flop offs. It's only me riding it, no "special" riders yet.
Post by: _X_ on August 11, 2013, 09:43:43 PM
Post by: citabjockey on August 11, 2013, 10:39:45 PM
It's only me riding it, no "special" riders yet.
Given you description of the edits maybe you ARE a special rider! (ducking now)
Looking forward to the video!
Now if we could just get that 360EFI going. And have Robbie Marshall ride it at Monster Energy Cup!
Post by: GerbilGronk on August 13, 2013, 11:03:19 AM
Post by: evo550 on August 13, 2013, 11:20:03 AM
Several "special" riders testing the EFI YZ at a trail ride in the weekend.Was it snowing?
Post by: Uniflow on August 13, 2013, 09:35:41 PM
Post by: _X_ on August 13, 2013, 09:41:46 PM
Post by: citabjockey on August 13, 2013, 10:13:14 PM
So this DFI stuff really works, eh?
Looks like a fun trail.
Post by: Uniflow on August 14, 2013, 12:40:39 AM
In saying this Wayne has just today changed the injection timing peramaters and it's crisper at the up to third / half throttle now. Still way more to be learned about this transfer port injection.
Citabjockey, I too am astounded at how clean the engine runs throughout it's rpm range with so little tuning time. I'm sure this tells us that transfer port injection is the way to go, short of full DFI. Remember we are getting an approx 14% fuel saving under the same conditions, this must point to less fuel short circuiting out the exhaust port.
Racer X, any time, just come on down, winter is best time although there are good rides on throughout the year. Summer is generally too dry to allow forest rides.
Post by: citabjockey on August 14, 2013, 01:51:45 AM
Yes it runs real well. They are different to ride, my standard one feels a little sharper up to about third / half throttle but then the EFI one doesn't hit as hard when coming on the power. Same top end power. I hate to compare but the EFI bike feels more 250F ish but just more power, everywhere.
In saying this Wayne has just today changed the injection timing peramaters and it's crisper at the up to third / half throttle now. Still way more to be learned about this transfer port injection.
Citabjockey, I too am astounded at how clean the engine runs throughout it's rpm range with so little tuning time. I'm sure this tells us that transfer port injection is the way to go, short of full DFI. Remember we are getting an approx 14% fuel saving under the same conditions, this must point to less fuel short circuiting out the exhaust port.
Racer X, any time, just come on down, winter is best time although there are good rides on throughout the year. Summer is generally too dry to allow forest rides.
Post by: Stusmoke on August 14, 2013, 03:38:22 AM
The DFI folks claim about 30% savings so you are getting half of that, sounds like a win to me! Congrats on your progress to date.Yes it runs real well. They are different to ride, my standard one feels a little sharper up to about third / half throttle but then the EFI one doesn't hit as hard when coming on the power. Same top end power. I hate to compare but the EFI bike feels more 250F ish but just more power, everywhere.
In saying this Wayne has just today changed the injection timing peramaters and it's crisper at the up to third / half throttle now. Still way more to be learned about this transfer port injection.
Citabjockey, I too am astounded at how clean the engine runs throughout it's rpm range with so little tuning time. I'm sure this tells us that transfer port injection is the way to go, short of full DFI. Remember we are getting an approx 14% fuel saving under the same conditions, this must point to less fuel short circuiting out the exhaust port.
Racer X, any time, just come on down, winter is best time although there are good rides on throughout the year. Summer is generally too dry to allow forest rides.
Yes a huge congratulations is in order. You've really given it the job it deserves. And, more importantly, shown that it can be done.
And just to throw this out there, have you had any reliability problems? Are you using the oil spray on the crank now?
Now try selling the idea to Yamaha...
Post by: Uniflow on August 14, 2013, 07:25:21 AM
That's the encouraging thing about this " conversion" there has been almost no problems. I made the throttle drum too good a fit and sometimes the throttle would hook up for a moment, not nice going into a corner with trees everywhere. Giving it a little clearance has fixed that problem. I gave the head too much compression ( if some is good, more must be better ) but that was quickly rectified, my fault. We have broken two kick start shafts now with the original ignition ( through the LINK ), at kick over the computer looses count of the flywheel pins and gets mixed up and then fires at the wrong time. We fixed this by fitting an Ignitec and using the LINK for fuel only. I made a new kick start shaft out of EN39B and case hardened it. Something else will bust now because the shaft never will anyway there is no kick back problem now with the Ignitec. I'm waiting on an Ignijet computer to try out, this should do the same job out of a much smaller package and much smaller price! That's about it, ride it in the rain, doesn't bother it. We are using a crude oiler system still, runs 60 to 1 oil in the fuel plus after 60% throttle a small valve opens to a fixed jet in the throttle body.
Post by: Stusmoke on August 14, 2013, 09:41:17 AM
Ha Ha Ha, sell the idea to Yamaha, their NZ technical guy seems not even interested. It's been waved under his nose. They are not interested!
That's the encouraging thing about this " conversion" there has been almost no problems. I made the throttle drum too good a fit and sometimes the throttle would hook up for a moment, not nice going into a corner with trees everywhere. Giving it a little clearance has fixed that problem. I gave the head too much compression ( if some is good, more must be better ) but that was quickly rectified, my fault. We have broken two kick start shafts now with the original ignition ( through the LINK ), at kick over the computer looses count of the flywheel pins and gets mixed up and then fires at the wrong time. We fixed this by fitting an Ignitec and using the LINK for fuel only. I made a new kick start shaft out of EN39B and case hardened it. Something else will bust now because the shaft never will anyway there is no kick back problem now with the Ignitec. I'm waiting on an Ignijet computer to try out, this should do the same job out of a much smaller package and much smaller price! That's about it, ride it in the rain, doesn't bother it. We are using a crude oiler system still, runs 60 to 1 oil in the fuel plus after 60% throttle a small valve opens to a fixed jet in the throttle body.
Shows how clever they are then. Imagine if they bought it, threw a million dollars of testing at it and dropped it on the market in 2015. Can you say sales rush? They'd go from not beng able to afford a factory effort to being able to forward five. You've clearly put alot of effort in, and I'm sure it was a fun project. Plus rewarding as balls
I know I've enjoyed reading about it.With the appropriate mapping changes, hopefully that 250Fness can be persuaded out of it
I've always said a 250 two stroke is like a 250F on some serious roids but does it all at an engine saving RPM.
Post by: citabjockey on August 14, 2013, 03:42:42 PM
Can you refresh my memory -- you were looking at a more reasonably priced computer. I don't think that is the LINK. Did that ever go anywhere?
Ha Ha Ha, sell the idea to Yamaha, their NZ technical guy seems not even interested. It's been waved under his nose. They are not interested!
That's the encouraging thing about this " conversion" there has been almost no problems. I made the throttle drum too good a fit and sometimes the throttle would hook up for a moment, not nice going into a corner with trees everywhere. Giving it a little clearance has fixed that problem. I gave the head too much compression ( if some is good, more must be better ) but that was quickly rectified, my fault. We have broken two kick start shafts now with the original ignition ( through the LINK ), at kick over the computer looses count of the flywheel pins and gets mixed up and then fires at the wrong time. We fixed this by fitting an Ignitec and using the LINK for fuel only. I made a new kick start shaft out of EN39B and case hardened it. Something else will bust now because the shaft never will anyway there is no kick back problem now with the Ignitec. I'm waiting on an Ignijet computer to try out, this should do the same job out of a much smaller package and much smaller price! That's about it, ride it in the rain, doesn't bother it. We are using a crude oiler system still, runs 60 to 1 oil in the fuel plus after 60% throttle a small valve opens to a fixed jet in the throttle body.
Post by: lauterbacher on August 14, 2013, 07:13:23 PM
Post by: Uniflow on August 14, 2013, 09:25:02 PM
Yes the flywheel has a 12 minus 1 pin setup ( eleven pins and a gap ) on it, the -1 ( missing pin ) is to give the computer a heads up that it's done a turn and is ready for another cycle. The computer not only counts the pins but also the time between them so at kick over there can be potential miss calculation. The moment it fires it will correct itself. The gap does not necessarily have to be at TDC as you can tell the computer the degrees from the gap to TDC, it will sort itself out. There are many ways around this but an Ignitec was an easy fix as I have them spare on the shelf, better spark too.
The LINK is a good computer but this new Ignjet should do as well at a much cheaper price, we will see. It's taken an unbelievable time to get hold of one, the order has been in for months.
Write a book, I hate writing!
Post by: _X_ on August 14, 2013, 09:31:55 PM
Post by: citabjockey on August 14, 2013, 09:42:13 PM
Write a book, I hate writing!
Then what the heck are you doing with all this posting?
If I am not mistaken it qualifies! ;-)So I can't believe that LINK can't wait for a full rotation (or at least till that gap comes around) to start sparking. Who the heck wrote the firmware???
Post by: Lolerbabop on August 14, 2013, 09:47:33 PM
EEEEEUUUUUUAAAHH!!!
Post by: Stusmoke on August 14, 2013, 11:16:37 PM
Write a book, I hate writing!
Then what the heck are you doing with all this posting?
So I can't believe that LINK can't wait for a full rotation (or at least till that gap comes around) to start sparking. Who the heck wrote the firmware???
Probably Apple... They're my go to blame for anything tech. Like honda in anything motor
So if theres a miscalculation when kicking over, does this make it a bitch to get started?I know that the RMZs first couple years on EFI made them even worse to start. Actually that pretty much goes for all of them...
Post by: GerbilGronk on August 15, 2013, 05:54:14 AM
how about a documentary? all you have to do is talk, drink and talk some more and we don't have to read.
Great idea. We need an armchair an open fire a pipe and a pair of comfortable slippers.
The EFI sounds quite different. In a good way. It looks like it hooks up really well. Looks easier to ride.
Post by: Stusmoke on August 15, 2013, 06:05:17 AM
how about a documentary? all you have to do is talk, drink and talk some more and we don't have to read.
Great idea. We need an armchair an open fire a pipe and a pair of comfortable slippers.
The EFI sounds quite different. In a good way. It looks like it hooks up really well. Looks easier to ride.
On the bad news side, that pretty much writes off the four strokes only real advantage in the lites class.
Post by: Jeram on September 02, 2013, 11:36:06 AM
20% less fuel burn this weekend. It depends on the type of usage, at lower speeds ( tighter track ) there is a larger benefit, more top end running = less fuel saving. I would imagine top out both bikes would be similar fuel consumption ( similar power ). Now it's getting exciting, every time out on the EFI bike is a little better as we change settings slightly. This weekend we got the raspy original feel back ( like my standard bike ) but we soon tuned that back out! It's much better / faster to ride with the smooth program installed. We even had a 250F rider have a go on the bike, he was quite shocked at how it went, it was hard to pry him off the bike after that.
With this torquey, tractable powerband, would it be possible to increase the revability of the 250 two stroke? Most are typically the midrange monsters as we know, but how about revving them out to their redline? And possible a slightly shorter stroke/bigger bore design to increase said redline?
MX seems to be the exception to the two stroke bore/stroke rule of thumb.
square bore/stroke is almost always optimal except for in moto-cross.
I always wonder why the didnt build the optimal 68x68mm 250-2T and then achieve the required bottom end/mid range/top end balance with pipe design and porting....
I am sure there is a very valid reason and it likely has nothing to do with HP, but more likely about usability and traction... and even more likely; laptimes.....
I always thought it was a traction issue. Whats the standard bore/stroke of the 250t offroad motor? 66.4x74 or something? 6mm off the stroke compensated for by a 1.6mm increase in bore, wouldn't that mean an increased turnover speed? 250 2ts struggle for traction in alot of places as they are, I always just put it down to a turnover speed too quick for the dirt. Four strokes can get away with it because they deliver a power stroke half as often.
72
Post by: Stusmoke on September 02, 2013, 11:45:16 AM
Post by: SachsGS on September 02, 2013, 02:45:24 PM
Post by: bearorso on September 02, 2013, 06:32:45 PM
Yet, they are Torque / soft(er) power oriented.
Optimal bore and stroke - it depends on a designers particular 'bent'. And each and every bloody one would argue furiously for their 'optimal' ratio.
Maico 250s, for a few decades, have had the 67 / 70 bore and stroke. My 320s had 76 x 70. When they had 72 stroke, and abandoned it, I have no idea. They may have 'pioneered' it, but they sure didn't stick with it.
Maicos fabled 490 /500 engines, were never a square design - both being a slightly oversquare engine. I think the one '500' that I know of, with a 'square' engine, is the KX500, at 84 x 84. Though, I'd not be surprised to be informed of other '500s' that are square engines.
Open Class 2t MXers, had such a surfiet of power and torque for their times, they were bouncing around with inumerable bore stroke ratios, when they were common.
4ts keep going for more and more revs, for getting their HP. So, more and more oversquare.
The 2t design, is so interweaved within itself - bore / stroke / crankcase volume / porting as making up the whole induction, and exhaust cycles, as to be incredibly varied in how it's done.
Someone coming out with "this is optimum", I just think of as one who has picked his 'favourite' - or, is subscribing to their particular worship of a designer / brand / model.
There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI, as the fuel component of the charge, will be less dependent on the 'whole engine' concept.
I think, for quite some time, the Evinrude E tech outboards have been based on a fairly oversquare ratio. It seems to be 96mm x 76mm for the V6s, and 91 x 66 with the V4s and inline engines. Of course, these engines are used in a much different context.
Post by: Stusmoke on September 03, 2013, 12:47:11 AM
And then you get the various 2t Trials Bike Engines - most of which are quite oversquare.
Yet, they are Torque / soft(er) power oriented.
Optimal bore and stroke - it depends on a designers particular 'bent'. And each and every bloody one would argue furiously for their 'optimal' ratio.
Maico 250s, for a few decades, have had the 67 / 70 bore and stroke. My 320s had 76 x 70. When they had 72 stroke, and abandoned it, I have no idea. They may have 'pioneered' it, but they sure didn't stick with it.
Maicos fabled 490 /500 engines, were never a square design - both being a slightly oversquare engine. I think the one '500' that I know of, with a 'square' engine, is the KX500, at 84 x 84. Though, I'd not be surprised to be informed of other '500s' that are square engines.
Open Class 2t MXers, had such a surfiet of power and torque for their times, they were bouncing around with inumerable bore stroke ratios, when they were common.
4ts keep going for more and more revs, for getting their HP. So, more and more oversquare.
The 2t design, is so interweaved within itself - bore / stroke / crankcase volume / porting as making up the whole induction, and exhaust cycles, as to be incredibly varied in how it's done.
Someone coming out with "this is optimum", I just think of as one who has picked his 'favourite' - or, is subscribing to their particular worship of a designer / brand / model.
There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI, as the fuel component of the charge, will be less dependent on the 'whole engine' concept.
I think, for quite some time, the Evinrude E tech outboards have been based on a fairly oversquare ratio. It seems to be 96mm x 76mm for the V6s, and 91 x 66 with the V4s and inline engines. Of course, these engines are used in a much different context.
I hadn't considered the crankcase volume and pressure implications of a motors bore/stroke but it makes sense. Like you said, using an electronic injection method, direct or not, turns it into a whole nother board game. If this rumoured 2014 DI 250 two stroke turns out to be true it will be interesting to see where things go.
Post by: Uniflow on September 03, 2013, 10:20:05 AM
Wayne Blackwood, right, with his YZ250EFI and some other guy hanging around we couldn't get rid of!
Post by: Jeram on September 03, 2013, 11:06:05 AM
There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI, as the fuel component of the charge, will be less dependent on the 'whole engine' concept.
I disagree with the idea that a DFI two stroke would require an over-square engine configuration. Its still a two stroke, it still relies on crank case induction and exhaust scavenging, just like almost all other DFI two strokes (with boats being the exception).
However a DFI trapping valve two stroke would probably make good use of a short stroke as it does not need the long stroke for additional exhaust time area.
Post by: bearorso on September 05, 2013, 08:04:27 AM
There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI, as the fuel component of the charge, will be less dependent on the 'whole engine' concept.
I disagree with the idea that a DFI two stroke would require an over-square engine configuration. Its still a two stroke, it still relies on crank case induction and exhaust scavenging, just like almost all other DFI two strokes (with boats being the exception).
However a DFI trapping valve two stroke would probably make good use of a short stroke as it does not need the long stroke for additional exhaust time area.
Disagree all you want young fellow.
As I wrote "There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI". Therefore, there will be disagreements.
I don't believe there is a need for 2ts in Motorcycles to go that route - chasing revs to get HP, as naturally aspirated 4ts do. That's through my own, perhaps 'old timers' viewpoint, on what I want from a 2t.
2ts can keep relatively long strokes, whilst doing battle with 4ts. Simple maths / time calculations show that 4ts "big bang advantage", so to speak, is gradually being negated by the revs they must go for, for power to compete against a 2t, at least for now. Though, Moto 3 rules (well, the max. bore rule of 81mm - shared with Moto 3 - is a somewhat of a 'control' in Moto GP) , are keeping a cap on revs.
But, as I wrote, there have been, and will remain to be, quite a varied opinion on what bore / stroke ratio is 'optimum'.
One Engineers "Optimum", will be anothers "Dud".
I gave the Evinrude dimensions as an example of what has been done, with a certain, pretty successful application of DFI 2 strokes.
I'll have to have a squizz at what the 2t Snowmobiles tend to use. It may be comparable to the
Outboards, as they may be more of a 'steady state' engine than a Motorcycle Engine ( but, I'd think, less so than an Outboard) would be. It, of course, may not be comparable, at all.
Post by: Jeram on September 05, 2013, 08:55:43 AM
There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI, as the fuel component of the charge, will be less dependent on the 'whole engine' concept.
I disagree with the idea that a DFI two stroke would require an over-square engine configuration. Its still a two stroke, it still relies on crank case induction and exhaust scavenging, just like almost all other DFI two strokes (with boats being the exception).
However a DFI trapping valve two stroke would probably make good use of a short stroke as it does not need the long stroke for additional exhaust time area.
Disagree all you want young fellow.
As I wrote "There is quite some arguement that 2ts will go to more oversquare engines, especially with such techs as DFI". Therefore, there will be disagreements.
I don't believe there is a need for 2ts in Motorcycles to go that route - chasing revs to get HP, as naturally aspirated 4ts do. That's through my own, perhaps 'old timers' viewpoint, on what I want from a 2t.
2ts can keep relatively long strokes, whilst doing battle with 4ts. Simple maths / time calculations show that 4ts "big bang advantage", so to speak, is gradually being negated by the revs they must go for, for power to compete against a 2t, at least for now. Though, Moto 3 rules (well, the max. bore rule of 81mm - shared with Moto 3 - is a somewhat of a 'control' in Moto GP) , are keeping a cap on revs.
But, as I wrote, there have been, and will remain to be, quite a varied opinion on what bore / stroke ratio is 'optimum'.
One Engineers "Optimum", will be anothers "Dud".
I gave the Evinrude dimensions as an example of what has been done, with a certain, pretty successful application of DFI 2 strokes.
I'll have to have a squizz at what the 2t Snowmobiles tend to use. It may be comparable to the
Outboards, as they may be more of a 'steady state' engine than a Motorcycle Engine ( but, I'd think, less so than an Outboard) would be. It, of course, may not be comparable, at all.
The 2T snowmobiles have a large bore/short stroke configuration, but the main point is that the bore/stroke rations did not change when the bikes went from carbied to EFI and then to DFI. The DFI two strokes did not alter their bore/stroke ration when they swapped from carbied to DFI either.
The bore/stroke rations remained constant because gas flow dynamics and power characteristics do not care how and when the fuel enters the engine, only that its there and dispersed in time for ignition to occur
So therefore I can only assume, and rightly so, that the bore/stroke will stay constant for two stroke motorcycles regardless of the fuel delivery type.
Post by: citabjockey on September 05, 2013, 03:11:28 PM
Post by: georgemicra on September 18, 2013, 11:33:10 PM
Post by: Uniflow on September 19, 2013, 03:50:50 AM
We will stick to the LINK ecu at the moment, we now have total control over injection timing.
This is totally off subject but my own YZ now has a Rekluse clutch in it, with a left handle bar rear brake. Foot brake is totally gone ( for old people with a worn out right hip ). It's a bit like a mountain bike with both leavers on the handle bars operating front and rear brake. Much better entry to the corner control.
Post by: Jeram on September 19, 2013, 06:14:07 AM
I thought I was using an Ignitech EFI ( ordered through Wobbly ) but it appears they might be no more! Wobbly's ordered is now five months old and no news. Not even contact from Emails. They have taken the money for the order. Unfortunate as it seemed like it might have been a good unit.
We will stick to the LINK ecu at the moment, we now have total control over injection timing.
This is totally off subject but my own YZ now has a Rekluse clutch in it, with a left handle bar rear brake. Foot brake is totally gone ( for old people with a worn out right hip ). It's a bit like a mountain bike with both leavers on the handle bars operating front and rear brake. Much better entry to the corner control.
That's very disappointing!
Ignitechs quality was lacking in a big way over the last 2 years, I've had numerous faults and very poor customer support. So its not suprising that theyve gone belly up. (I dont know whether they have or not, but what your saying doesnt sound good)
Post by: georgemicra on September 19, 2013, 12:15:38 PM
Post by: lauterbacher on September 19, 2013, 01:33:22 PM
Post by: rsmith on February 27, 2017, 05:27:41 PM
I would like to let him know that I was able to recover this thread and see what happened with this project.
--Ron.
Post by: Coop on February 28, 2017, 03:38:21 PM
Post by: citabjockey on February 28, 2017, 11:04:35 PM
Post by: Flettner on March 03, 2017, 04:47:08 PM
Post by: rsmith on March 03, 2017, 07:14:31 PM
I'm here, just not so often these days. Thought this TSM had died, nothing seemed to be happening. Fire away.
It did die actually, Charles wasn't doing backups so I had to go to some somewhat extraordinary means to recover it.
This topic about the EFI YZ project is how I found the site way back when. Uniflow says in there somewhere that he was using this site to document the project and so I wanted to let him know that I had gotten it back.
So is Flettner Uniflow? or do you know how to get a hold of Uniflow?
Thanks for checking in either way, we are working on generating more traffic here to hopefully get the discussions flowing again.
--Ron.
--Ron.
Post by: TMKIWI on March 03, 2017, 07:41:15 PM
Post by: rsmith on March 06, 2017, 01:33:27 PM
Yes Fletther and Uniflow are one and the same. Crazy bugger with a dodgy hip. :)
Okay then, I guess I don't need to let him know!
I would be interested in where this project went though.
Post by: Flettner on March 06, 2017, 10:10:55 PM
But the F9 Kawasaki (mine) is still running fine, in fact better than ever as I've widened the exhaust port somewhat. The fuel injection has not been touched in years now. Chews through the ethanol but the result is 50 crankshaft HP, well worth it.
There is another YZ project running in Australia, Nathan Coleman. His bike is used on the street and he has a very good go pro video of it running around. On youtube.
Post by: rsmith on March 07, 2017, 10:48:01 AM
It is also interesting to see how much hasn't changed now in 2017. There were several post with speculations that EFI would be stock on the 2015 bikes. Now of course we know that hasn't happened outside of OSSA's trials bike.
Back around page 6 in this you had pictures of case half forms for a rotary valve intake if I remember correctly.
Did you end up making those?
Post by: Flettner on March 07, 2017, 11:32:24 AM
There was a lot of work done on this engine about two years ago (perhaps more?) and its to the point where I made an error in the RV housing. At the same time the Kawasaki (the ideas test engine for this 360) was running well but not exceptional so I lost interest. BUT now the Kawasaki is going so well I've got renewed interest in the 360 engine. I've also worked out a way around the RV housing problem, i'm going to use two slide gibs, one as I am now to alter the shut time and a second one that will change the open time. Both gibs will also act as the ECU controlled throttle.
To be fair I've been off on a bit of a tangent with the sleeve valve engine (running now) and an experimental HCCI (homogenius charge compression ignition) engine. And the casting of some other unusual cylinders.
Also part of the problem with the 360 was getting a decent cylinder casting, now all fixed, I've got three nice clean cylinders with blade type power valves. Best of all is I now can consistently cast porous free clean cylinders, also learnt to use LM13 alloy, better for nikasil to stick to. ALSO the Link controller I wanted to use has come down in price and has shrunk physically too, small enough to fit to a motorcycle now.
But as usual these projects are after hours and funded by me so time will always be an issue.
And lately I've been spending a lot of time riding the Kawasaki in different events, sooo much fun! Love that power!
Post by: rsmith on March 07, 2017, 12:27:05 PM
Is the HCCI design similar to what Honda was calling Activated Radical Combustion back about 20 years ago? Where is switches between SI and CI at a certain RPM?
That Kawasaki is awesome. Good thing your racing organization is not like AHRMA, those guys have a rule against everything. I think next they will be requiring period correct spoke nipples to go with there existing rule about having to run fanged rims.
Post by: Flettner on March 07, 2017, 03:31:59 PM
No, my HCCI is full time, a bit like a diesel in that it has an open inlet and is regulated by fuel only. problem with diesels is they can't mix and burn the fuel fast enough for true high speed operation but if the fuel is pre mixed like any fourstroke petrol engine then it's just a matter of raising the combustion chamber pressure at the right time to cause combustion. Mine has a small piston in the head running at twice the crank speed, this ensures a rapid pressure rise at the right time. It's on youtube somewhere, running. Just a modified Yamaha AG 100 engine. The video is pretty crappy but it does show the engine running and I've learn't a lot from this. I can now regulate it with the fuel volume.
Post by: rsmith on March 07, 2017, 04:24:32 PM
That's pretty damn cool. I will go hunt up the video.
--Ron.
Post by: Flettner on March 07, 2017, 08:09:01 PM
Post by: rsmith on March 07, 2017, 09:59:30 PM
The spray gun as a carburetor substitute was an interesting approach, did you do that for better control?
Post by: Flettner on March 07, 2017, 11:55:14 PM
I thought the surging was because, as the revs increased the volumeric efficiency drops off (no pipe) so effective compression drops, so combustion stops. revs decay until the cycle starts again. If there was a load on the engine it would have run constant without surging. The little piston in the head on this version had only just enough compression to run so didn't take much reduction in induction volume for there to be not enough compression to run.
The run away at the end I think was caused by the little piston heating up (even though there were water cooling pipes from the head there was no water, too lazy to hook it up) and initiating the combustion with the aid of the pressure rise. Pressure and extra heat.
This little piston also aids in recovering energy from the combustion.
An interesting side note, the little piston is at it's TDC when the big piston is at BDC and TDC so technically it's volume doesn't come into the measurement for cc rating of an engine (for racing purposes). But mid stroke the cylinder will have more volume to accept more fuel air (than a normal engine) AND mid stroke on the other side the little piston will have helped expand the gases (for a give cc rating) . Neat aye.
I'm in the process of building a new cylinder for this engine and a new crankshaft. The crankshaft is a crank within a crank. It produces a straight line motion for the rod so the rod can be sealed off. Top end will be sealed from the oiled bottom end, engine will burn no oil. https://youtu.be/-2AhNvDFNlQ
The rod in this video was dissolved by my local Anodizer so I'm building a new one. It's going to be sent to the US for hard chroming, we can't hard chrome 7075 alloy in NZ, allegedly.
The spray gun was used as I needed an 'injection system' of some sort. I can't throttle the inlet and the jetting would have been too hard to adjust on the fly. Engine is controlled by fuel only. A bit like the diesel in that no matter how small the amount of fuel inducted, the pressure rise will set it off. We don't need a 12 to 1 fuel air ratio around the spark plug like a normal engine, there is no spark plug!
Post by: Flettner on March 08, 2017, 12:14:34 AM
And walk around https://youtu.be/TmXFkbD3s5g
Post by: eprovenzano on March 09, 2017, 01:15:19 PM
Post by: rsmith on March 09, 2017, 09:22:00 PM
What about something like a Lectron carb with a metering rod? Machine the slide so it just acts as a guide for the metering rod and only creates minimal restriction.
--Ron.
Post by: Flettner on March 09, 2017, 11:41:27 PM
I have a cunning cylinder (or at least I think so) based on the FOS system lined up for this HCCI job.
The FOS system is a cylinder where there is a ring of exhaust ports, then underneath a ring of transfers. In this cylinder I've run three of the transfers direct into the cylinder from atmosphere and the other three are boost type ports pointing up into the combustion chamber from the crank case. This system uses the same direct inlet transfers as piston port to the crank case, double jobs.
The injectors (x3), located in the direct transfers, these injectors only fuel as the crank case inducts and are shut off as the direct transfers feed air into the cylinder via the "pull" from the chamber. This will supply fuel air up into the combustion chamber and fresh air under this charge. SO only fresh air should be lost to the exhaust and fuel air trapped in the combustion chamber. This type of cylinder offers enormous blow down time, needed for high rev's.
In reality I don't know but lets see what happens?
I'll see if I can find a picture of this cylinder.
Post by: Flettner on March 10, 2017, 12:06:24 AM
One of three direct inlet ports, also feed the crank case at TDC (piston ported)
(http://i1056.photobucket.com/albums/t380/uniflow/20161204_162844_zpsreltqwda.jpg)
Pattern
(http://i1056.photobucket.com/albums/t380/uniflow/20161207_194516_zpsx3yitgpx.jpg)
Some sand cores
(http://i1056.photobucket.com/albums/t380/uniflow/20161207_202958_zpsghooc5g2.jpg)
ready to pour
(http://i1056.photobucket.com/albums/t380/uniflow/20170109_211950_zpsju25xfwv.jpg)
Three of these ports are the high pressure transfers aimed at the combustion chamber and the other three are water jacket inlets. Ring is just a feeder system to supply molten alloy evenly and not turbulent, cut off afterward.
Post by: rsmith on March 12, 2017, 02:31:14 PM
I am having a hard time understanding how the fuel charge is going to be prevented from short circuiting out the exhaust. If it swirls as it reaches the top of the combustion chamber as is desirable to keep the fuel in suspension isn't it going to come back down into the air stream headed out the exhaust ports?
--Ron.
Post by: Flettner on March 12, 2017, 10:45:25 PM
https://youtu.be/2p0dyPu7Gcs
https://youtu.be/dT4btNAmjz0
https://youtu.be/Hodd8oyiawk
This is an FOS concept, an earlier one I made. This is to test a sliding cylinder idea (and the FOS system)
In this concept, it uses an ordinary crankcase, all six transfers pump at the same time. relies heavily on exhaust pulse to help with the pumping as there is not much crank case compression. pipe does most of the work any way in a normal twostroke. If you don't believe me, take the pipe off your MX bike and see how it runs.
In my HCCI cylinder the six ports are divided up into three crank case transfers and three direct from atmosphere transfers. The idea is that the HCCI crank case pumping volume is smaller than the engines capacity (so pumps less), is high pressure (so will still pump where there is not enough blow down time at high RPM). The exhaust is restricted so as to maintain a positive back pressure coupled with the low volume high pressure transfer (from three ports) should restrict fuel from exciting the combustion chamber, any leakage to the exhaust should be via the direct to air transfers (air only). as the pressure in the exhaust rises so does the pulse energy, the sign wave will still go negative an help draw air from the open transfers. Hopefully this will happen under the fuel air trapped up in the combustion chamber, this will be over rich to account for the extra air delivered from below. Clear as mud? There are a lot of ifs and buts, I find this kind of suck it and see interesting as sometimes something unexpected throws up.
Post by: _X_ on March 13, 2017, 03:53:27 PM
Post by: Flettner on March 13, 2017, 04:15:06 PM
Post by: rsmith on March 13, 2017, 09:06:12 PM
If I understand correctly you are saying that the exhaust pressure will be positive when the fuel charge is introduced and the fresh air charge will help hold the fuel charge above the exhaust ports when the exhaust pressure goes negative.
Yes? Maybe?
--Ron.
Post by: Flettner on March 14, 2017, 12:22:28 PM
Post by: bearorso on April 05, 2017, 08:05:04 AM
It's on page 3, in the 'The Sweep Rider'. There's a couple of pictures of his handiwork, and, it even reveals his real name.......................
Post by: rsmith on April 08, 2017, 08:33:32 AM
Flettner (Uniflow) and this thread is a large part of why I bought this site and spent all the hours to get as much of the old content back as I could.
--Ron.