Help with valve shims!

Shim thickness in .05mm steps, not .001mm.

 

I've done a bunch of sportbikes. It's not really a lack of oil changes that determine changes in tolerance. Notice usually they get tighter (esp. exhaust), not looser. It's from the hot valve slamming into the head and burying itself deeper into the seat.

just saw your post dirty pool.....carry on.

 

So what your saying is that grinding them down would "unharden" them??

 

The op said he knows a guy who could, he never said to do it in his garage

 

Shit, that bump reminds me. I still haven't done these

 

when you heat up hardened metals they soften and so must be retreated to harden them again, this is done by dropping red hot metal into oil bath and quickly cooled to reharden the metal, if allowed to cool slowly the metal will not have the same wear qualities or strength as hardened steel does.

it all depends on how hot they get when you are grinding them, if done slowly with mild friction and a cooling liquid then it is possible to wear them down to the desired thickness without changing the hardness of the metal but this is not something joe bob can or should try to do in his garage.

if you want to do half assed shade tree mechanic work then go for it but don't think you have the right to call yourself a mechanic if you do work like that, especially when you can just buy the correct shims you need for a few dollars and a few days waiting time for them to arrive.

grinding your own shims is akin to reusing old spark plugs, sure you can do it and the engine will run, but its not something anyone should be doing unless they have a machine shop that will do it for them to assure its done correctly and at the correct thicknesses.