Motorcycle Repair: ZRX1200 top end noise, connecting rod bearing, piston valve

Question
I was recently riding my 2002 ZRX1200 when I begin to hear an abnormal noise. I turned around to go back home and the noise got louder before I got home. It is a knocking sound and it seems to be coming from the top end. Also it increases as the RPMs increase. I took the head cover off and didn't seem anything abnormal. I checked the valve clearance and nearly all the valves were tight. Should I just shim the valves and see if that fixes my problem or is it possibly something worse??

Answer
Kyle,

-First see if you can check the compression
to see if any cylinders are low.
It should ideally have over 150 psi
on all cylinders. It is possible that
something broke or is loose in the engine.

-Is the bike still running? If so, try
using a long screwdriver or rod to
pinpoint the location of the noise.
Hold your ear to the rod and move it
around to different spots.
If you have a mechanics stethascope better yet.

-You should not run it long if it
is knocking badly.

-it could be some worn cam chain tensioners (common)
guides or chains.

-could be piston/valve problem.
if you can't figure it out from listening
or looking it may require the top
end be diassembled to find the problem.
I advise getting a service manual for any engine work.

-Worst case would be a bad connecting rod bearing.

Try here for added info:
http://www.zzrbikes.com/index.php