Posting about my buddies z400.. ya'll may know. He had a problem with the shim on top of the valve spring. Same valves and everything that came out of it but the stock shims that came in it wouldn't fit. Had to go to a smaller width shim. Anyone know what causes this or why it would happen? Not sure if any of you have experienced the same problem. Any information would help. Thanks.

 

Did you place the original shim back to its original valve/tappet/ keepers/bucket/ etc? You should have all the parts originally for that valve and that valve only(assuming you didn't intermix the valve parts) Did you by chance inter mix your intake shims with your exhaust? 285 intake/312-315 exhaust. You would have some issues if you did. Parts will start forming a custom fit over time. All valve train components must go back to their original location(intake or exhaust) with their original parts. Try swapping the shim with the other one. Good Luck!!!