valve shim forum input - and a question

[mark m thornton <markmt@gte.net>]

I'd like to second - or is that third? - the advice to refrain from 
moving long-used valve shims from one valve stem to another.  Agree this 
can bring on quite rapid increases in valve clearance in cases where the 
valve stem chamfer in the new location does not match up with the 
slight indentation worn in the old shim.

I've noticed two kinds of shims.  One has a plain cylindrical outer 
surface.  The other is darker material and has a circumferential groove. 
Are these early and late?

cheers,

mark m thornton
seattle washington usa