piston slap?

[lovetoridezx6r]

hey all.. real quick i was getting my bottom end rebuilt and i had a kawasaki mechanic check out all my top-end while it was apart. The bike ran like **** and had a bad rh crank seal (95 kx 125). when i took the cylinder in the mechanic honed it real quick for me. put the bike back together and it sounded (from descriptions i've heard) like it had some pretty bad piston slap. only thing i did there was clean the exhaust valves (i timed them when put back) and got the cylinder honed. could the honing create that slap? haven't had time to take it apart so i don't know what the piston and cylinder look like. thanks in advance for any advice or help!

 

[2strokerfun]

Honing a bore too large will create piston slap and worse. Measuring the bore and piston before reassmbly is highly recommended.

 

[lovetoridezx6r]

works for me. thanks.

 

[ZeCatfish]

Isn't that a nikasil plated cylinder? If so WTF would you hone, that would trash the plating requireing it to be replated.

 

[lovetoridezx6r]

well i don't know much yet about dirtbikes, but a mechanic re-honed it, so i assume he knows what he's doing. The cylinder was re-sleeved in the past... if that makes a difference.

 

[2strokerfun]

Re-sleeving should make no difference. But if your piston is somewhat worn already, a hone may have enlarged the cylinder just enough where you now notice it. If it actually is piston slap you hear, you need to measure the piston and cylinder. I can't say I've ever heard piston slap in one of my bikes. Have you let the mechanic listen to it? If the mechanic just honed the cylinder to get a good cross hatch, he might not have had reason to measure it, but there is a chance your piston was worn beyond spec to begin with.

 

[Ol'89r]

If the engine has been re-sleeved with a cast iron sleeve, the piston will make more noise. A cast iron sleeve requires more clearance between the piston and cylinder than a plated cylinder and will produce more noise. If your piston is worn and you are using a cast iron sleeve, that could be the problem.

Like others have suggested, check your clearance and mic the piston for wear.

ZeCatfish.

Nikasil plated cylinders do require a light hone when you re-ring.

Just my $ .02

 

[lovetoridezx6r]

alright well thlanks for all your help. I'm actually taking it into the shop to have the mechanic work on it. thanks again.