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Rebuilt... Now She Smokes...

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Ok, just did a rebuild. Piston, rings, valves... whole ball of wax. Took the head to a buddy's shop for the valves, i did everything else.

Took me forever to get the timing right because the cam chain fell off the crank gear at the bottom. I took the side cover off, fixed that, got it timed... all back together. Started fine first with a little bit of smoke, then more, then more. I put a liberal amount of oil on the rings and cylinder side walls, but i didnt think i put that much. I got scared and shut it off after about 8-10 mins of running time and smoking.

Should i let it run and see if it clears up/ burns the oil i mightve put on the piston? Or did i do something wrong? The rings were seated fine, I'm sure of that.

Any suggestions would be appreciated. Thanks!

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i would just ride it..and dont putt around on it..get down on it a couple times. the pressure against the rings will force them against the cylinder and let them seal better. i jus finished my topend rebuild on my raptor and it smoked like a freight train when it started and smoked until i rode it for a little while. and it still smokes when i first start it up after its cooled down but after it gets to opperating temp it clears right on up. did you put new valve seals in while u had it apart??

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Get it up to running temperature and take it for a ride. If it smokes more under accelleration, it's the rings. If it smokes when decellerating, it's the intake valve guides.

Hope that helps.

Ride on

Brewster

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Just got done with a rebuild also.Mine did not smoke one bit.I just wiped the cylinder wall lightly with oil nothing heavy.Ride it but be careful.If it continues to smoke possibly the rings were put in wrong.Good luck.

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Ok, i let it warm up... again a little smoke, then increasingly more. Rode down the street... Smokes heavy during acceleration. Its too wet to really ride it, but i went down the street a few times, got on it, and it is still smoking.

I know the rings were fine, they were seated in the grooves. Top ring with the marking facing up. Then the oil ring devides the other two in the other groove. I dont know what i couldve messed up.

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Did u hone the cylinder. You should have if u didnt. U have to break the glaze so your new rings will seat properly. Also apply very little oil when rebuilding it. Ive also heard of assembling it dry but i myself didnt trust that theory and it gave me peice of mind putting some oil on it. If your that worried just take it apart. hone it. and do it over. You might be losing a bit of power but you probly couldnt notice it. My bike smokes when cold thats all. I wouldnt worry about it too much man. Ride it hard.

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I assembled mine dry and had no problems with smoking at all.

Be sure you have the ring gaps offset correctly on the oil control rings.

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I guess that I am going to go ahead and tear it down again tomorrow to check the rings. I'd rather be safe than sorry. I'm getting good at this tearing down and putting it back together thing anyway lol.

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Just did our this past week.

New valves, springs seals, wiseco hi copm piston.

Ball honed the cylinder, wiped with oil, piston/rings dry.

Filled with non synthetic oil, Kendal 10W40, Cycled the motor 10-15 times with the kill button on.

The motor gives a small puff when first started but it decreases the more we run it. We have 2 hours on it of practice and trail riding. The puff you can barely see. Oil level has not moved enough to even tell.

I would check that oil ring as mentioned it is a bugger to get in correctly the first few times you do it. :)

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Not an expert here but just using logic, if you soaked all the stuff in oil like your supposed to, I would think it would be smoking for the first ride because that extra oil is burning off?

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Thanks everyone for your input! I dont know what my sorry butt would do without thumpertalk sometimes. :)

I tore it down one more time and found that the top oil ring had slipped and bent. The cylinder and everything is fine, just got to get a new ring and make sure its in properly this time!

It really does pay to be safe then sorry. I'm glad I didnt just try to wait it out and hope they would seat.

Thanks!

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