Ok to hone?

[Bikenstitches]

My 04 WR250F smokes, so I took down the top end to inspect. No obvious piston or cylinder wear, so I'm going to re-ring it. I plan to hone it, but worry that that there is some kind of coating. Is honing normal practice on this engine?

Thanks

[marine89]

NO!!!!!! do not hone it, the cylinder is coated and if worn or damaged then you just replace it.

[762SPR]

Unless you have a diamond hone you won't take off the nikasil plating inside the cylinder from a quick hone... maybe if you sat there all day doing it... If you're putting new rings in, then hit it with some scotch brite and WD-40. Give it a good scrub to deglaze it and you should be good to go. It's also OK to use a ball or bar hone but if you don't have one then scotch bright will work fine. Basically all you want to do is scrub out all of the steel chunks from the rings seating last time and combustion goo that has gummed up the crass hatching that was put in after it was plated.

I have always used this method for break in and it has worked for me.

http://www.mototuneu..._in_secrets.htm

Edited November 20, 2012 by 762SPR

[Bikenstitches]

Thanks for the replies. I'm hoping not to toss the cylinder, as it doesn't look worn, but I know that I should do something to seat new rings.

BTW, the oil ring is not as expanded as the other two rings; is that typical, or is it my likely problem of the engine smoking?

The scotch brite solution makes sense to me.

Tom