You'd probably destroy the case hardening. It's also difficult to have it stay perfectly flat and even.

 

Yep, and probably screws up the contact finish.

 

As said above ^.
Plus, there is a possibility that you'll use that shim to another location (last shim job on the KLR, the exhaust shims moved to the intake or v/v and bought two new shims). My local shop will trade shims with me.

 

My local shop "trades" shims for $2. Your old shim and $2 gets you a new one. Its better than buying the whole set for $80. IMHO

 

I did some research and shim material is typically cold rolled 4140, so when the time comes I'll just make some on the lathe...

 

07 KLX with 8k miles and head has never been removed, all carb and intake mods were performed years ago. Have never touched a thing since and runs better than new.....like a bat out of hell actually!!!