Commando cylinder deck height

Does anybody know what the distance between and mounting flange and top flange should be on a 750 cylinder? When I check the position of the pistons in the bores at TDC with no base gasket the pistons are up 0.050" above the top of the cylinder. I'm using MAP rods and GPM flat top pistons. The rods check okay at 5.875" between centers, not sure about the piston height. I can shim the cylinder up but this seems odd and I'd like to find out where the discrepency is.

.050 above the barrel would be normal for a 750 at TDC. I can measure a 750 barrel for you tomorrow if you need that measurement. Jim

I get 4.545" for a 750 barrel from bottom of flange to the top deck. The stock flat top pistons have an aprox. .175" recess cut in for the valves. They measure 1.550 from the center of the wrist pin to the top of the piston.

Thanks for the feedback. My cylinder measures 4.545-4.550 and the new GPM pistons have the same deck height as the old ones. Current plan is to put a 0.021" shim under the cylinder which will make the piston even with the top of a 0.030" thick head gasket. The head has been milled 0.040" and the chambers cc at 46.5 ml. There is still about 0.070" depth to the recess counter bored in the head so there should be enough clearance. With the flat top pistons and my 0.030" over cylinders this will give me a little over 9:1. Hopefully I'll have good valve/piston clearance.
I may be able to take another 0.010" off the head and still have adequate clearance but I probably won't mess with it. This looks like about the most compression you can get with a stock head and flat top pistons.
Thanks again.

I think you have done what is reasonable for a road bike I put the head on the barell (you can leave the pushrods out) without gasket but with plasticine on the pistocrown then rotate the crank to see if it clears
than you know you have the thickness of the gasket as clearance in your squish
take the head back off and assemble with gasket but this time put the pushrods in and with plasticine on the valvecutouts repete and check your spring lenghts.take head off and check gap left by valves on plasticine
at the same time checq if your springs have enough clearance for coilbound
I run 42cc on the road