Ytm 200 engine knock

[daniel_250r]

Just picked up a ytm200 for 250$ finally gotit running and the engine has a pretty good knock especially when warmed up i took the clutch cover off and found nothing loose and moved the crank back and forth and didnt feel the rod moving much or at all. The oil filter was Full of debris and aluminium shavings. Any help appreciated thanks

[Jmoozy27]

Check valve adjustment. Does it smoke? Compression?

[daniel_250r]

Havent checked valve adjustment And yes it does smoke but its more of a bottom end noise from what i can hear

[YamaBoss]

Is the noise similar to this?

http://youtu.be/psf4fYNuzjI

Mine makes the same noise. I took the cover off and the centrifugal clutch nut was hand tight. I tightened it back up and it still made a similar noise. After I ran it some more I noticed a winding down noise and a clunk when I shut it off. That tells me the one way bearing is bad so I just ordered one of them. I am going to put it in and see if that helps.

My brothers had a similar noise before we changed out the clutches. But with new clutch plates, bearing, and centrifugal clutch his is quiet as can be. So im assuming it is just a clutch thing and not something like a crank bearing. I guess we will see once I get the bearing in.

[350for350]

A loose cam chain can cause a knocking noise at the front of the engine. It's not real loud, but you can hear it while riding. I ran across one that had a loud knocking towards the front of the engine. It turned out that the cam journals, ( I think) were worn badly. I could move the cam up and down in the head about a half inch by hand. I just swapped out the head and the noise was gone. Hopefully that's an extremely rare noise. I can't think that it would happen too often.