Here's the story, One day I herd what I thought was valve train noise, when idleing I herd click click click click. Any way I thought that I just need to adjust the vales, so I took it to the dealer to check and adjust the valve clearance. So I got my quad back and they said that they went into the head and said that the clicking noise was not the valves, it was that the piston was slapping the head. The only wat to fix this, he said, was to bore it .40 over or something. He said this because, my cylinder was opening up.

I need help on what to do, should I just but a 440 kit w/ sleeve?

Any help/opinions would be greatfuly apreshated, thanks. [img]i/expressions/face-icon-small-frown.gif[/img]

 

Try replacing the wrist pin and bearing. If not then replace the rod with the stock stroke legnth. It sounds like your piston is clattering up and down too far. Like a wheel bearing gone bad its wobbling (the piston) thats the only way i can explain it. Plus if you have to bore it your rod (if aftermarket) will be stronger and more able to stay up with the task.

 

Thanks, I'll tell'em that.

anyone else.

 

My buddy has a KFX and had this same similar noise. It turned out that the timing chain was stretched all the way out and the tensioner, located on the top right rear of the cyclinder was full extended in.. He put a new timing chain in it and it stopped the noise...Now though he has a problem again, thinking it was the valves he bout a shim kit and adjusted them out. This didn't help...the dealership told him that the KFX is know to stretch the valve stems! Looks like a rebuild now!

 

What motor mods does he have? (If any)

 

It has only been jetted, no internal motor mods.

 

bluenuts is right about the cam chain being bad,but if it is that i would buy the h-d DID chain not a factory one. and i would look at the athena kit for the kfx/z .comes with a new cylinder ,no boring

 

What he said.[img]i/expressions/face-icon-small-cool.gif[/img]

 

Yep...I've heard this from alot of guys with the KFX, on the other hand i haven't heard of any Z400's with the cam chain problem.. go figure, same motor!