I am in the middle of doing a valve adjustment. my first time and it's easy. i just measured all 4 valves, my feeler gauge only goes to .04mm and the intake valves are def needing replacement shims. Now the exhaust valves fit the .04mm gauge pretty well, only a slight bit of resistance.. i figure the .03 guage would tell me they have room. Now my ques is should i bother replacing the exhaust valves with new shims? I plan on selling the bike very soon so should i just sell it w/ only the intake shims done or should i go and change them now. If i was keeping the bike i'd def replace em now since i have it all apart.

P.S. I am no using a shim tool, i am using 2 screw drivers and a magnetic pickup, works pretty well, just need to apply alot of pressure. It looks like doing the exhaust side will be alil tight using this method.

Quote from: wildbill on October 30, 2007, 01:12:26 PM
my ques is should i bother replacing the exhaust valves with new shims?

Which shims are you proposing to put in?

Let's take a semi-educated guess, and place the actual clearance at .035mm ... and let's suppose that you have a 2.65mm shim in the bucket.  The next-thinnest shim would be 2.60mm thick, which will give you a clearance of .085mm  ... which is slightly out-of-spec.

Now let's suppose that the clearance is right at .03mm.  The same 2.60mm will give you a clearance of .08mm, which is right at the top of the in-spec range.  Granted, it's probably better for exhaust valves to be too loose rather than too tight ... but it's best to have them "in spec".

How do you decide which way to go if you can't measure the actual clearance?

Here are my suggestions:
    1) See if you can get your hands on an even thinner shim ... something 2.55mm (in the
        above example) or thinner.  This will let you use thicker feeler blades (or even
        combinations of feeler blades) to arrive at a definite value for the clearance.
    2) If you come up with a "borderline" clearance (right at .03mm) go with the next
        thinner shim.
    3) If all of this is too much hassle, or would take you past your "SOLD!" deadline, I
        wouldn't feel bad about selling the bike with the current clearances.  As long as
        you can spin those exhaust shim buckets!

PS - If you're very lucky, you might find a 'tween-sized shim in your bike or at your dealership's service department.  (Ask about the "coffee can of swapped-out shims" that they probably have on a shelf somewhere.)  I'm talking about a stock shim with a thickness you can't buy from the catalog ... like 2.62mm.  If I remember correctly, they come printed with an X next to the numbers.  These 'tween-sized shims are the only way to go from a "borderline" clearance to one that's in the middle of the in-spec range.  (Yes, I once tried sanding down a shim using fine wet/dry sandpaper.  After about 40 minutes I MIGHT have taken away a 10,000th of an inch ... but I doubt it.)

Thank you kerry, i hoped you would answer lol. My left intake valve is 260mm and reads 260mm, my right intake valve reads 265mm but i used my caliper and it came out to about 267mm. I am def gonna get a 255mm shim for the left valve since the .04 feeler wouldn't even try to get in there. the right valve thats at 267mm i am gonna use the 260mm shim from the left valve to see if that gives me in spec clearance. If not i will order a smaller shim for it or try the dealer. I think i will just leave the exhaust valves since they are in spec and i really wanna sell the bike. Thanks again for the help.

Never got all that fussy about them myself.  I've been thinking in inches for 75 years now so I still work in inches.     Spec is .03-.08mm or .001-.003" and my feeler guage starts at .002" so if it measures .002 or larger I go with the measurement.  If a .002" feeler won't go and I can turn the bucket freely with my fingertip I mark it .001" and let it go for another 8k miles or put in a .05mm=.002" smaller shim if I have one to get more clearance.

My old 97 GS went 88k miles without changing an intake valve shim and my 02 GS still has the original intake shims at 55k miles.  I've found that exhaust valve clearances tend to get smaller as the exhaust valves recede into the seats so if I change an exhaust valve shim I go to .004 or .005" clearance if I have that size shim, won't need changed again as soon.  Works for me and has for over 130k miles and 18 valve checks on 2 GSs so far.

http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg

Quote from: gsJack on October 30, 2007, 08:55:46 PM
Never got all that fussy about them myself.  I've been thinking in inches for 75 years now so I still work in inches.     Spec is .03-.08mm or .001-.003" and my feeler guage starts at .002" so if it measures .002 or larger I go with the measurement.  If a .002" feeler won't go and I can turn the bucket freely with my fingertip I mark it .001" and let it go for another 8k miles or put in a .05mm=.002" smaller shim if I have one to get more clearance.

My old 97 GS went 88k miles without changing an intake valve shim and my 02 GS still has the original intake shims at 55k miles.  I've found that exhaust valve clearances tend to get smaller as the exhaust valves recede into the seats so if I change an exhaust valve shim I go to .004 or .005" clearance if I have that size shim, won't need changed again as soon.  Works for me and has for over 130k miles and 18 valve checks on 2 GSs so far.

http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg

Well my bike is a 95.. it's its first valve check and has 9,000 miles on it. Jack it has the opposite problem, the intake shims are real tight, the .04 guage wont even try to get in there. The exhaust valves are pretty good, the .04mm fits pretty well inbtween the cam and shim. I am gonna order 2 shims today. A 255mm for the first intake since stock its 260mm. The 2nd intake reads 265mm but meausres 267mm. I am gonna throw the 260mm shim i already have in the 2nd intake side and check the clearance, it should work and i should only have to order 1 shim than. I don't have an inbetweeny like kerry mentioned.. i will check the dealership to see if they may have one. Thanks for the info guys.