ok heres the dumb ass question of the day ...... i cant get a .o4 mm feeler guage into my exhaust vave .... but i seen a post that if you can spin the bucket freely you still have enough clearance and both of mine spin freely!!! any ideas ??? i know the valves are to be between .03-.08mm with .05 being ideal ..
have a good holliday folks
If you can spin the bucket, you don't necessarily have enough clearance, you just have more than *zero* clearance. If you can't get a 0.04 mm feeler in, you need to replace the shim.
beRto is right. (See the TOO TIGHT section on THIS CHART (http://www.bbburma.net/Documents/ValveAdjustmentVideo/GS500_Valve_Shim_Selection_Chart.gif).)
The possibility exists that your clearance is just under .04mm, and that going to the next-thinnest shim will put your clearance over .08mm ... but without a .03mm feeler blade you won't know for sure until you replace the shim and measure.
I'm one of those that feels that any clearance is adeqate, if the bucket spins freely with the fingertip I'll mark it .001" and let it go and have done so quite a few times. If I have a .002" = .05 mm smaller shim I'll go ahead and change it, not concerned if the clearance goes over a bit on exhaust valves. I've let them go with .004" and .005" clearance.
My 97 GS went 88k miles on the original engine and never had an intake valve shim changed. The 02 has 56k miles on it now and I did change an intake shim once but changed it back next time so it also has original intake shims.
The exhaust valves tend to recede into the seats requiring smaller shims from time to time, one of the 97 GS exhaust valves was down to a min 215 shim at the end. When I change exhaust valve shims I give them a little extra clearance.
My valve clearance/shim changes on the 97 and 02 GSs:
http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg
You can't go wrong doing it like beRto and Kerry advise but on my bikes I do it my way, your bike is your choice. :laugh:
thanks for the info guys , i had 2.70 shims in both exhaust vaves and i had less than .04 clearance so i dropped into a local bike shop and he swapped me for some 2.65 and now i have .08 clearance so it worked out well now i just have to put it back togetherand wait till the snow melts ....... but in the meantime ,waiting for a katana shock that i bid on e-bay to make the upgrade to the rear suspension.
I had just less than .03. Since the GS shims tend to seat rather than get bigger I would rather overshoot (to .09 or something) than to keep a barely-ok shim in.