Tolerences for Valve Shimming

Hi all:

I've checked valve clearances and found that some will need new shims and some are near tolerance. So, should re-shim only the ones that are out of spec? or re-shim more valves so that everyone is within spec?

Or, should I go as far as re-shimming so that all are as close to middle of tolerance as shim sizes will permit. :blink:

83GPz750, yosi 4/1, factory airbox, jetted, 94k, topend rebuilt at 71k

Many thanks in advance

Unitrak wrote:

Hi all:

I've checked valve clearances and found that some will need new shims and some are near tolerance. So, should re-shim only the ones that are out of spec? or re-shim more valves so that everyone is within spec?

Or, should I go as far as re-shimming so that all are as close to middle of tolerance as shim sizes will permit. :blink:

83GPz750, yosi 4/1, factory airbox, jetted, 94k, topend rebuilt at 71k

Many thanks in advance

AKAIK, the current recommendations from the air cooled guru's is to shim all the valves to the looser end of the spec. Yes this means the valves may tick a little more, but as the they wear, they have a tendency to tighten up and a valve thats quietly too tight may go un-noticed and cause trouble i.e.: it can burn.

hope this helps...Sam

I just did mine yesterday, and I think I did them sloppy. (Im a bit out of the KZ Loop) I wouldnt though if you are using under a 230 shim. I am running 265's almost all across with 6 clearance and ill recheck them in the spring. Its no big deal to change if you have the spacer tool.

Thanks for the info, I'll aim to be on the loose side as I've allways been a bit of a slacker;)