hi,

i have a 2001 recon 250. I replaced the piston rings according to specs from service manual... Still smokes but not near as bad as it used to before. Could this be due to just a large amount of oil deposit on the inside of the exaust pipes still burning??

als,, the engine is knocking, ive been told piston slap or crank rod loose. I havnt taken it apart yet but does anyone have tips on a true location of the issue before i tear down that part of the engine to find out thats not the issue ? Or maybe pictures that coul show a warn piston or crank rod that could show a possible piston slap issue or crank rod knock?

thanks for the help in advance.

 

What was your piston to jug clearance?
Was the bore honed?
What was the ring end clearance?

 

everything was specifically put back to factory recommendations... i dont remember the clearances of hand, i left my service manual at the house im working on it right now, umm the bore was not honed, BUT there was black deposit inside the bore... it hadnt crusted or anything, it actually came off with a couple wipes from a damp washcloth. and looked clean when it dried so i assumed it should still be fine.

 

And there's your problem. New rings won't seat on an old bore. Also, I have never seen an old bore that does not have tapper or out of roundness or some sorte of defect. Even with just a few miles on it. Most need to be bored but some can get away with a hone job.

 

the smoking will stop. you will need to ride the fourwheeler several hours, stopping every 30 minutes to allow it to cool. the knock is normal because you reused your same cylinder. ATVS dont knock like cars because of warn out crank bearings, or rod bearings. because fourwheelers have roller bearings. dont worry about the knock (unless its rediculously loud and the motor actually vibrates when it makes the noise) and the smoking will eventually stop