Piston/ring replacement now I have issues

Bike ran good before this, but I knew I was burning some oil and it was getting up there in hours.  So I pulled it apart put a new weisco piston and ring set and oem headgasket in.  The cylinder looked good, factory cross hatching was  visible, but I didn't hone or touch the cylinder (should I have?).  Put everything back together and it doesn't want to run, after a lot of kicking I have got it to run but doesn't want to stay running, also sounds more chattery than before.  I talked to someone that's more experienced with this stuff, and they said maybe I should have had the cylinder honed, is this right?  Havent taken it back apart yet, but think Ive caused any damage to the new rings or piston? thanks for any help

Did you clean the cylinder with hot soapy water and a green scotchbrite pad ? Usually if the

Cylinder looks good that's all that's nessasary for the most part , is it smoking when it's running any worse than before the teardown , all that chattering could just be your decomp not installed right or something , I'm by no means a professional just thinking out loud !

You likely have the cam timing off a tooth and/or you didn't relieve the cam chain tensioner's tension before reinstalling it.

And yes, you should have scotchbrited and then cleaned the cylinder. If it's only been run very briefly, you could disassemble it and fix the issues.

Edited by Eddie8v

Yes its only been run very briefly, as like I say it didn't even want to run.  When I disassemble it is there any signs to look for on the rings that they may be damaged think ill be ok re-using these new rings or should I buy another set? thanks for the replys

I am sure they're fine, just take a look at them to be sure the outer sealing surface is ok.

Not to hijack but scotchbrite does what exactly?

It's aggressive enough to remove any deposited piston aluminum from the cylinder wall's Nikasil crosshatch, but won't hurt the hard Nikasil.

Ok sounds good I might get a new set of rings just for piece of mind. Think red scotch brite is too aggressive? Just that we have lots of it at work, otherwise I'll go buy some green/ blue stuff

Not to sound like a dick, but if your having problem getting the bike back together correctly, I'd get someone who knows whats going on working along side you, before going back inside. I wouldn't take it apart again just for a hone. You won't do damage to the new rings by not honing the cyl. At worst the rings won't seal as well as they might have if it were done correctly.


These bikes aren't that difficult to work on. As easy as they are to work on, they're even easier to eff up which can get expensive. 

Take a look at cam timing before tearing it all the way down again.

Did you relieve the tension on the cam chain tensioner?

Don't think I said I was having trouble getting it back together

Like others have said.  Check the cam timing.  Just did a similar piston and rings job and didn't do any honing or scotchbrite work.  Started up and ran great first kick.  Did take my time watching some youtube videos and making sure we got everything right.

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