1981 gs650g tappet clearance, insight needed please

[Duttry98]

I should've took one. I can this evening.

[Nessism]

I've seen heat induced discoloration on valve buckets and cams before ranging in color from gold/brown to blue. If a valve doesn't have any clearance anymore it will run hot because it can't cool via the valve seat, not sure if this is the root cause of those discolored parts though. I think letting the bike idle too long while in the driveway is often to blame.

[hannibal]

Rookie question: does the motor leave the factory with the same sized shims in all positions? Do all motors leave with the same set of shims?

[tkent02]

No, but they are mostly around 2.80 for starters.

[Nessism]

No, but they are mostly around 2.80 for starters.

My first 850 came from the factory with mostly 2.60's. Maybe it was a monday morning bike and the guy grinding the seats had a headache?

[tkent02]

Could be a Friday night motor. The guy couldn't be bothered to measure and just ground the hell out of it.

[Duttry98]

Here's the mysterious blued shim......

[tkent02]

That's not heat, some of them just look that way. Something to do with how they hardened the steel or something.

[habsdoc]

Yes, that colour is just from the heat treating used to harden the shim. Perfectly good to use.