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14 yz450f puff of smoke on start up??

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Hey guys,

Just got a 2014 yz450f about 3 weeks ago. Ive been out twice with it besides messing around in the yard a couple times. Never realized any smoke on first start up throttle blimp, until now after an oil change.....

Changed the oil in it yesterday (mobil 1 4 t) and put 32oz (1qt) in it. The previous owner said he put this amount even though the book calls for .73 oil change and 1 qt on teardown. When I changed the oil im pretty meticulous and even raised the front end to get EVERY drop I could out. Put in a quart and changed the filter. Today I went to test it for leaks and started her up, once running for a few seconds blimped the throttle and saw a small puff of smoke (couldnt tell color but did look more dark and not blue) and a faint smell of burning oil. After that though no blimp of the throttle would produce another "puff" so thought the smell was oil residue from the change. Went out hours later and same thing...small puff when I blimped it for the first time,  nothing after and slight smell of oil burning. 

The mechanic in me says possible valve seals (probably just way overthinking after spending 3500 on a bike)...but the problem does NOT show up again on engine decel nor after the first start up throttle blimp. Could it be the small amount I "over filled" (literally if anything like .2 of a quart). Does anyone else have this experience? Bike has 60hrs tops on it with 10 on piston.

GURUS PLEASE HELP! Am I just overly worried about nothing?!?!

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Ah some people have noted a puff here and there as I recall. Maybe a hair overfilled. You say 10 hrs on a piston if it’s a aftermarket especially a Wiesco or two ring piston well then. But why worry until there is a real problem.  

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Thank you man appreciate the reply!

It is a wiseco piston,  just curious but why do you say that? Are the wiseco pistons single or double ring? I didnt put it in and I believe (if I remember correctly) when I put one in my 2003 it was a single ring...but that was 5 years ago lol and honestly forget. 

Im not to worried as in freaking out as again I only see it on the first blimp, and honestly couldn't catch the color of the smoke to verify oil or fuel (rich condition), but I did just spend 3500 on it was was bothered enough to post on here haha. Ive never spent this much on a bike so its "brand" new to me. 

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$3500. these days isn’t much. But if you ever pull it apart the Weisco’s seem to use more piston clearance I don’t know how many rings they use. I prefer three but many use two nowadays. The Cylinder Works new barrel and pistons are cheep and seem to work. The stock pistons are quite good if the barrel isn’t too worn that’s one of the best pistons to use.   

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I know 3500 its much, especially when guys are buying 9k bikes! haha but it's alot to me, im used to buying 1500-2k 10 year old bikes so im stoked to have something 4 years old (october 2014 it rolled off the showroom floor).

I wish the original owner went that route, but he is the one that put the piston in. Just glad atleast it has had a top end done so I get some time until I do a complete top a d bottom. When I do, I will go the cylinder works complete kit route as ive used them before with good results. 

Thanks again Stevethesnake for the reply, any little input is much appreciated. 

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