Messages

1

For Sale / 2006 yz125

« on: September 16, 2012, 08:08:07 AM »

I'm selling my 06 YZ125. The bike has low hours but can't tell you how many exact hours. Original piston. I just replaced the ring thinking it may need it but everything was good yet. But since I had the top end off I replaced it anyways. I really try and take care of my bikes. Original sprocket and chain. Well I do have a 49 tooth instead of 48 in the back but still have the 48 which looks good too. I'm currently stationed down at Eglin AFB FL and will travel for the right price to sell. only upgrades would be 1 1/8th Renthal fat bars, white rear fender, aluminum throttle tube, 1 tooth larger rear sprocket, MH3 front tire and newer dunlop 756 rear. The bike no longer has the renthal twin wall bars and hand guards. I took them off and installed them on my 07 ktm 200xc. It still has 1 1/8th bars
 Phone- 850-225-9302 call/text
Thanks
Mike

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 20, 2012, 06:41:46 PM »

hey here is a short video of the bike before it fried the piston.
http://contour.com/stories/2001-tm-racing

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 20, 2012, 02:27:30 AM »

Hey thmike, have you done a compression test on the TM? I'm curious what the actual readings are, I recall some 90's CR Hondas reading upwards of 200 PSI.

I have not. I just put the wossner piston in it and went with thicker base gaskets to see if I can get it to run pump without doing head mods. Yes I know I will be losing some bottom end but I would rather loose some bottom then having to run race gas all the time. If its so bad I can't stand riding it I will send the head out to get rechambered.

The bike started right away. The motor sounds a lot smoother. I think I had piston slap before so I went with a 53.97 vs the 53.95 that was in it. Only did one heat cycle tonight. Will continue some more tomorrow and retorque some bolts. I'll see if i can get my hands on a compression tester. Don't currently have one at the moment!

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 19, 2012, 03:40:23 PM »

recommend away! lol. I just would like it to run good on pump! 93 octane..

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 19, 2012, 05:16:41 AM »

what kind of info do i need to get my head rechambered...2t institute..are you in the states?

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 18, 2012, 09:11:43 AM »

I've got a new piston and rings on the way. As well as jets(175 &178). Hopefully I can get some higher octane fuel before I leave for my Michigan trip. I'm taking both of my bikes to Michigan to do some racing and visiting family. I'm in the USAF and stationed down in florida. I also bought  some parts to put a new ring in the YZ125. Figured I'd do it just to be safe. She's been great and I got it a few months ago with almost no hours on it.

I'm going to retard the timing some on the TM and hopefully have some race gas for it also. I have a buddy whos going out with his friend on a Cigar boat, one of the race looking boats and he said he could get me some 114 or 110..can't remember.  If its 114 i'm going to mix it with premium 3:1. 110 will be 2:1. I'm hoping for the best anyways. I'll ride it one day at the track and take the head off to inspect the piston once i'm done with the first few rides. And if it looks crappy then it will be 50/50 or getting the head modded. I think that may be my best bet but for now I'm trying to keep the budget low. I already has about 700 into this bike. But it is a TM.

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Photos & Videos / Introduction/pics of new bike

« on: July 18, 2012, 08:00:52 AM »

I've used domintator at 32:1 in my yz125 and my buddy uses it at 32:1 in both of his yz250s.  Just because the bottle say 50:1 it won't hurt to run 32:1. If she's fouling plugs it will be because of the pilot most likely. Sometime adjusting the air fuel screw will take care of it..sometimes droping a pilot will help. I'm making the switch to Castor 927 on my yz125 next weekend. Amsoil is good stuff. I remember reading 50:1 or manufactur recommendation..somthing like that anyways

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 16, 2012, 09:49:50 AM »

Previous owner..one of my best friends back home. (I joined the military and went back home on leave and this bike was in the shed collecting dust because of cranks bearings were starting to fail so I took it back with me as a project). He always ran 50/50 race gas because he said it always ran better. Said it had alittle pinging when not running race gas and that rings lasted longer when running race gas mix. He raced the bike back when it was new and til about 06. It was pretty muched parked in 06. The base gasket that was in it was the second thinnest base gasket. So I thought/hoping running a thicker base gasket would keep me from running race/pump gas. I guess I was wrong. I was told by a TM guy that it may be possible to run a thicker base gasket and lower the compression since TMs like running higher octane then what you can get at the pump here. I've been doing some research and found out if my squish is to big that it can also cause the same problems I had. So I'm thinking about going with the same thickness base gasket that was in it, jetting it back to stock, 175main vs 172main that in it and try and retard timing 1-3 degrees to get away from detanation. And I'm trying to save money by not getting the head cut but looks like if it doesn't run well after this and i'm getting detanation I will get the head cut.
He always ran 50:1 with synthetic oil and I'm running 32:1 with Maxima Castor 927. I'm also guessing because the bike was leaned out for 50:1 and race/pump gas that it may be alittle lean

This didn't happen on 2 short rides by the way. I rode it all day at the track one day. Then all day the week after trail riding.  So about 2-3 hours on the bike when it happen. I just ordered a wossner piston today.

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 14, 2012, 07:06:06 AM »

i think I got more than 4 gaskets. I went with the thickest base gasket..lol

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 12, 2012, 10:37:35 AM »

I think the squish band needs attention to, I don't think rasing the cylinder is the answer as it has no mid range now.

I've been thinking about the squish...But I know if thats right I will have to run race gas. I'm trying to to go to expensive with this bike. Its a 01 and more of play toy then my race bike. I won't mind a pipey bike. Heck thats fun! But what I'm gathering its 100% detanation.  The motor did feel real hot. Cases wise was a lot hotter then my yz125.

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 11, 2012, 09:05:17 PM »

No obvious seizure marks but lots of erosion - must be due to detonation. I would check ignition timing, either lower compression ratio or stick to race/pump gas mix and enrichen fuel mixture slightly to bring down combustion temperatures. 

So go up on the main jet, take some timing away, and lower the compression. If I do all three I should be able to get rid of this detanation issue.

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 11, 2012, 02:09:32 PM »

175 to 172 won't be the difference between ok and seizure. My guess is either too much timing or compression and not enough octane.

It didn't seize though..thank god. lol. just lost compression.

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 11, 2012, 01:57:56 PM »

IT didn't happen when I was letting off...soon as I shifted to six and started going through the gear was when it happen. It was a 1 mile hole the bike wide open either. It was get through the gears and slow down. But I didn't chop the throttle.

A guy on thumpertalk said there was a lot a detenation. I know TMs love race gas/pump mix at the minimum but I was hoping to get it right on pump. Does anyone know if running a thicker base gasket along with retarding the timing would prevent this?

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Technical / 2001 TM RAcing 125mx Piston meltdown

« on: July 11, 2012, 09:53:34 AM »

Just recently rebuilt this bike from the ground up a few weeks ago. Well for the most part. Motor wise I replaced everything it needed. I've been messing with jetting for mid-range since the bike doesn't have the power of my 2006 yz125.  Seemed like I got is pretty good. It doesn't have good bottom-mid but top end is awesome. Typical 125 I guess. Well I felt like I had it running good, so I decided to tell my buddy on his 04 rm125 which is ported to do some drags with me. On the second run, (running the bikes to 6th then slowing down), I did pull from him til I hit 6th and then lost power. Bummer! well no big deal..its only a 2 stroke. Thank god I made the switch back to them!
 
I pulled the piston out and this is what it looked like today. There was aluminum built up on the nikasil at the very top of the cylinder and some on the head. No scaring to the walls, head is all cleaned up now and the aluminum just came right off the nikasil.

Jetting INFO-The bike from the factory comes with 175 main and has a 172 in it. The friend I got the bike off of used to run 50/50 race/pump in the bike at 50:1 and I'm running 32:1 pump gas. So I'm guessing she's lean. Maybe igntion is advanced. No pinging from the motor..that I can tell anyways. Runing Maxima Castor 927 oil.

This was the second time on the bike since build. First was at the track and second was trail riding with my wife and friends. Figured I could get some jetting figured out that I was having problems with at the track.

Here are the pics of the piston

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Photos & Videos / 2006 yz125 ContourRoam

« on: May 29, 2012, 04:44:56 AM »

26yr old..I've only been riding two wheels for about 2 yrs..and Was deployed for 6 months of those 2 years.. This yz125 has been a fun bike. I miss my ktm 250sx but having a lot of fun on this lil zinger!