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Xr400 smoke after new cylinder kit..?

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Hello this is my first post!

So I have a 99 xr400

I just put a new cylinder kit on. ( It was ran without oil previously .. )when I start the bike it smokes a lot. I'm happy to get it running at least. But I'm not sure now... Will it stop smoking eventually? Or is something wrong and I should not run it.

I really need some advice here.

Thank you

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Did you happen to replace the piston and rings? If its smoking it means its burn oil. (Most of the time) what color is the smoke?

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I bought one that had just been rebuilt with a couple hours on it. It would have a tiny bit of smoke if I revved it and let off sometimes. But it seemed to clear up after riding it more.

Does it smoke just when it starts and then clear up?

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Hello this is my first post!

So I have a 99 xr400

I just put a new cylinder kit on. ( It was ran without oil previously .. )when I start the bike it smokes a lot. I'm happy to get it running at least. But I'm not sure now... Will it stop smoking eventually? Or is something wrong and I should not run it.

I really need some advice here.

Thank you

lets say by new cylinder kit you mean, piston - rings - and cylinder. and it was installed correctly and the bike smoked like a mofo, i would say its the valve guides are shot maybe

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Yea I bought a cylinder kit. Piston, rings, cylinder. It starts up and seems to run pretty good! It smokes a lot white. Haven't really let it run too long, I didn't know

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Did you lube the shit out of the parts when you reinstalled them? I used to be guilty of that a long time ago...

Edited by orangyktmthing

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Well I thought I lubed everything.. The bike was previously ran with no oil.. So maybe needs some work on the valves as well?

Well I thought I lubed everything.. The bike was previously ran with no oil.. So maybe needs some work on the valves as well?

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New rings smoke until they seat.  This can happen almost immediately or take several minutes depending on materials, lubricants, and workmanship.  As soon as they seat, the smoking stops.

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Also a small amount of oil is coming from the exhaust. How long do they take to seat. I haven't ran it too long because it sure is smokey!

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Instead of running it go ride it and put some load on the engine. Try to keep changing rpm.

If it doesn't improve in about 30 minutes of that I'd say you have another problem.

Typically valve seals leak oil when the engine is off. It leaks down into the cylinder and makes it smoke on a cold start until it burns off.

If it's the rings, it will smoke and just not quit ever.

I'd try that and if it still smokes do a compression test.

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Also a small amount of oil is coming from the exhaust. How long do they take to seat. I haven't ran it too long because it sure is smokey!

 

I don't know what your assembly procedure was in the way of lubricants.

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