i am new to this, sorry if something does get screwed up! i have owned the machine for awhile now and have done quite abit of work to it; front diff, carb, bearings etc. so i know the machine fairly well, so i think... all the problems i have had i have fixed myself expect this damn knock in the top end!! the knock comes and goes. i have reset the valves twice but the knock is still there... i am now thinking it could be the cam chain?? i need someone that knows these machines inside and out that can help!

 

Yes could be cam chain......Does it sound like traveling noise? Does it go away when engine speed is increased? You can take the value covers back off an look thru the head cover an see cam and chain to if chain is loose...Alot of time if chain is noisey it will get quiter when engine speed is increased because the movement of cam and crank tighten up chain.........

 

I haven't yet took the valve covers off again, but I did do some other work and had it running and it started and ran great but after few minutes the knock came back, when I gave it throttle the knock just increased in speed with the motor. needless to say I took it for a short ride and afterwards it ran great, no knock. so I just went to run it again and the knock is back. now like you have said about the cam chain, if it was the chain wouldn't it always be there and not come and go? so maybe could it be a valve on its way out?

 

Chain Adjuster could be slipping loosing up when get hot, IMO top end should be good. We need more information on this sound..Thanks. ...........does it sound like traveling noise when engine is running

 

well i have it apart couldnt see the cam chain very well. but i put it back together enough to start it to video when the knock starts. it was running for just under 5 minutes before it started knocking. here is the video of it so you can take a listen aswell, the knock starts at 40-43 seconds into the video.

 

sounds like the cam chain to me. i would have pulled the cam chain cover and observed the chain with the engine running. but yeah, i say it was the cam chain.