Valve adjustment - need some expert advice.

G'day TT members, well I finally did it took the plunge and opened up the top end to inspect the valve clearances. The last few rides I have noticed a noise coming from the top end and thought Oh, Oh..tight valves. After downloading Dougies instructions the top end was opened and I discovered that both the inlet and outlet valves were tight and out of specification with what is recommended in the manual. Inlet clearance 0.10mm. Outlet 0.20mm. Taking a deep breath and tightening my sphincter muscle I lifted the cam covers, inspected the valve shim numbers and proceeded to put everything back in place. Beware the halfmoon clip, it nearly fell into the motor! What I am unsure of is the position of the decompression shaft. At the moment with everything reassembled there is 5mm play at the decomp lever and the decomp shaft is pushed all the way into the motor.

Q. Should the flat side of the decomp shaft be facing the exhaust valve? Should it be pushed all the way into the motor?

Q. When reinstalling the cam chain tensioner, is it simple enough to let the tensioner "spring back" and unwind onto the chain? Does that make sense to anyone? What is your method for resetting the chain tension? I accidently stripped some of thread from the 12mm adjustment bolt. By using loctite on the remaining thread will that be enough? It does not seem like a critical fastener.

I plan to order the replacement valve shims this week and hopefully will have them in the bike by next weekend. Any further advice/encouraging comments from the likes of Taffy "cam master", James Dean "jet king", Clark "guru" Mason would be greatly appreciated.


Simon "mechanically inept" Grummett :)

PS. By wrapping the frame in a plastic bag prevents mud and dust from falling into the motor.

Grum: The compression release shaft is positioned so that the flat side of the shaft is facing the exhaust valve bucket. That shaft acts very much like a cam in that when the shaft turns, the round curved side of the shaft acts like the cam lobe and pushes down on the bucket. You DEFINITELY want a little play at that shaft, otherwise, it could be in a postion that won't allow the valve to close 100%. Actually, it's pretty easy to look down onto the top of the one exhaust valve that the shaft is situated over and see when its in it's proper position. I Don't think you could even get it in wrong since it would have to actually open the valve a little first before it would slide in and that would be nearly impossible.

When I reinstalled the cam chain tensioner, I held a small screwdriver as best as I could and kept the tension off while I slipped the assembly into the cavity and then gently let go of the screwdriver. I could feel and hear the tensioner release but not all that violently. after snugging down the two anchor bolts, I then reinserted the screwdriver and took a little tension off the chain and then let it go again. I could tell that it was operating correctly. By the way, I oiled the tensioner before I reinstalled it.

That bolt is more of an access plug than anything else. As long as you have it sealed and loctited well so that it doesn't leak and won't fall out, you're fine.

[This message has been edited by Boit (edited 10-29-2000).]

Thanks for the quick reply Boit,

you have relieved some of the doubts I have had on completing this job. I have never opened the top end of my bike before let alone muck around with valve adjustment. I'll let you know at the end of the week how everything turned out.



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