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Offline Uniflow

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YZ 250 EFI
« Reply #225 on: July 22, 2013, 04:18:28 AM »
Ironically the Kawasaki 350 had this system originally with oil going through the right hand main ( and rotary valve housing ) then flung out to a tin centripetal thing bolted to the crank, caught the oil being flung out  and feed it into the bigend pin. Then on to the rollers via a hole leading out. I tossed all this out years ago, what were they thinking, I thought :D.  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.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Uniflow

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« Reply #226 on: July 24, 2013, 09:09:23 PM »
Both bikes will be at Maddix park Tauranga this Saturday afternoon. This time the Go Pro will be charged, card empty, ready to go! 
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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« Reply #227 on: July 24, 2013, 09:34:40 PM »
cool uni, cant wait to see footage.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Uniflow

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« Reply #228 on: August 11, 2013, 09:23:30 PM »
We have a few Trail rides completed now with the YZ EFI , no dramas, just as you would expect from a new bike off the shelf! It appears to be running at 14% less fuel burn compared to my carbed YZ, same tracks, same rider ( me ), same day. Hardly accurate enough results to go public with but this has been what we have measured so far.
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. 
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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« Reply #229 on: August 11, 2013, 09:43:43 PM »
maybe you could piece together the crash and burn for our enjoyment? i have a funny one im dieing to post. yes its of me.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline citabjockey

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YZ 250 EFI
« Reply #230 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!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »
Yamaha CT3, RT3, MX125, SC500, Toy Prius, Diesel F250 (it all balances out)

Offline GerbilGronk

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« Reply #231 on: August 13, 2013, 11:03:19 AM »
Several  "special" riders testing the EFI YZ at a trail ride in the weekend. :)

« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline evo550

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« Reply #232 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?
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Uniflow

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« Reply #233 on: August 13, 2013, 09:35:41 PM »
Thank you Dave for putting video up. The bike in the front is the EFI one, the one following is my standard unit. I went out and did 85 Km first on the EFI bike, and my standard one, then we did this video run, I was buggered.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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« Reply #234 on: August 13, 2013, 09:41:46 PM »
how was the comparison? like the riding area, i could see myself there one day.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline citabjockey

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« Reply #235 on: August 13, 2013, 10:13:14 PM »
Sounds like its running VERY clean bottom to top!
So this DFI stuff really works, eh?

Looks like a fun trail.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »
Yamaha CT3, RT3, MX125, SC500, Toy Prius, Diesel F250 (it all balances out)

Offline Uniflow

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« Reply #236 on: August 14, 2013, 12:40:39 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.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline citabjockey

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« Reply #237 on: August 14, 2013, 01:51:45 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.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »
Yamaha CT3, RT3, MX125, SC500, Toy Prius, Diesel F250 (it all balances out)

Offline Stusmoke

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« Reply #238 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...  8) :P
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline Uniflow

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« Reply #239 on: August 14, 2013, 07:25:21 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.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »