Why does the GS500 have such a short valve adjustment interval?

[MaxD]

Sledge, putting together my own kit like that is what I have been doing.  I've got it all but the shims. 

I don't know if the K&L shims are breakage prone parts or not.  But, my own perception of Chinese products may be different from many.  I'm in the electronics business, and in my home lab I have several Chinese test instruments.  They are all top quality, for about 1/3 the price of similar American products.   On the other hand, I read a story about some Chinese baby food that had sawdust in it and was starving the babies.  So, it's case by case.   

[Bluesmudge]

My GS made it to 20,000 miles before it had its first valve check but the clearances were dangerously small at that point. Was causing all sorts of problems.
Opened the clearances up to .08 - .12 and have only had to swap one shim between 20,000 and 40,000 miles.

I think Suzuki was just covering their ass because some people ride their bikes hard and the occasional GS does need its shims changed earlier.

[twocool]

Answer:

To prevent burning the exhaust valve.

(anybody who owned an original VW Beetle knows this very well..)


Cookie

[HPP8140]

My GS made it to 20,000 miles before it had its first valve check but the clearances were dangerously small at that point. Was causing all sorts of problems.
Opened the clearances up to .08 - .12 and have only had to swap one shim between 20,000 and 40,000 miles.

I think Suzuki was just covering their ass because some people ride their bikes hard and the occasional GS does need its shims changed earlier.

Looks like you have the F model with oil cooler. I wouldn't stretch the E models past 10k without checking exhaust valves at least.

I've bought a few of these bikes where the PO did not check and the left exhaust valve usually suffers. Had to drop down 3 sizes on my current 02 to get clearance....when this happens the bike will run fine, but that exhaust valve will continue to wear much faster than the others.

I bought the bike with 14k mi and am now at 60k and I'm using a shim 2 sizes smaller than Suzuki recommends....what a pity the bike runs great but that one valve will shorten the life.

[MaxD]

HPP8140, that's great info to have.  My own bike is an old 2001 E model, but a like new garage queen with very low miles that I just lucked into for a very fair price.  I'm trying to ride that luck by keeping those exhaust valves trimmed in nearly perfectly at the high end of the spec.  gsJack ran a long term experiment on that, and he found that when he was right at 0.08 (high end of spec) or a little more that the valve recession slowed way down.  With that, he was able to get 100k miles out of that engine. 

I'm no mechanic, but I read a little on the subject.  I note in "The Essential Guide to Motorcycle Maintenance" p. 25: "Normally when a valve seat needs renewing it is simply recut with a special tool."  Maybe that head you have that is badly recessed can be saved. 

[MaxD]

HPP8140, I did a quick on-line check and I do see some services fixing those valve seats, and claiming they are better than new with better heat conduction.  For example:

http://www.ridejbi.com/jbi-cylinder-head-valve-seat-replacement/

These guys are in Chandler, AZ, USA, and report they replace a seat for $60, and then only $40 for any additional seats in the same head. 

[HPP8140]

HPP8140, I did a quick on-line check and I do see some services fixing those valve seats, and claiming they are better than new with better heat conduction.  For example:

http://www.ridejbi.com/jbi-cylinder-head-valve-seat-replacement/

These guys are in Chandler, AZ, USA, and report they replace a seat for $60, and then only $40 for any additional seats in the same head.

Thanks for the info. Looks like that would involve removing, shipping and re-installing the head, which I don't know how to do.

I'm currently looking for a lower mileage 2001-2002 (harder to find and in good condition) and will sell my current bike cheap...disclosing the situation. It still has a lot of life for someone who doesn't ride as much.