valve adjustment woes

[gssuzukixxx]

I am not sure what I am doing wrong. I checked and adjusted the valve clearances on my '77 GS750 last spring. I had to change a couple of shims but in the end I was able to slide a .002" (.051mm) feeler gage into all the lifter/cam spaces. I turned the engine over a couple of times and checked them again before l closed it up. Now, less than 1000km later I check them and find a couple that are too tight.

I followed the method on Bascliff's web site in both cases. I hardly ride this bike but every time I check the valves there are some that are too tight.

Any thoughts as to what is going on here.

Thanks in advance
Brian

[Ghostgs1]

Hi GS, If the valves were too tight before the last adjustment, they may have had a bit of carbon build up on the seats. After a bit of operation the carbon has worn off? That is my best guess. Ray

[gssuzukixxx]

OK I think I may have found the problem. What I didn't mention in my initial post is that I had taken the cam chain idler off to double check my valve timing prior to checking valve clearances. When I put the idler back on I think the cam chain was very tight because when the idler was off the tensioner had moved in.

So I loosened the tensioner mounting bolts off and backed the tensioner knob off while I tightened the tensioner bolts up again. Now I can feel a bit of slack in the cam chain and now the valves that were showing up as tight before are OK again. It was all valves inboard of the cam bearings that were showing tight which made me think of the cam chain being too tight and pulling the cam shafted down tight against cam bearings.

Now I just hope I didn't damage the cam chain by being too tight.

I never reolized it before but whenever the idler is off the tensioner must be reset when putting the idler back on.

Brian

[Steve]

Well, they do tighten up with use, but should not be getting tight that soon.

As long as you can still slide your 0.0015" feeler in there, you will be OK.

.