Valve Adjustment Shims

[Gone in 60]

I got nuthin. If I need a new shim, I order from Amazon (none of the local dealers even know what shims are), check ‘em wirh my Harbor Freight digital micrometer to verify thickness and toss them in. If the final reading is close to what I want I call it good.

I’ve never seen a non-flat shim.

What do you consider "close"? Within the +/- .001 inch tolerance from nominal?

I'd call .001" a tolerable tolerance. I tend to do the math to put my valves on the slightly loose side, so if the variance is to the tight side, I'll still be happy. 

That being said, I'm currently monitoring valve clearances on six BMWs, my Enfield 650 and my Bonneville (which I just measured and shimmed within a few thousand miles ago).
My NC750X hasn't gotten to a mileage that needs an inspection yet.  I still haven't touched my CB1100, and probably won't.