All good suggestions
Here’s a more thorough recap.
Went through all the bearing locations one at a time with the other end supported by a lower half shell. I learned that three locations were pinching the split. Two on intake, one on exhaust. I lightly eased the very edges of the split on the caps and head, just like removing an edge burr. This fixed the problem, cams move easily now when fully assembled.
this begs the question, why now?
I did not save the old bearing shells so I can’t compare them but the only thing that changed was the bearing shells. I’m going to have to settle on a minor difference in the newer bearing parts and perhaps an unfortunate stack up of manufacturing tolerances, it’s all I can think of. It took so little to fix it just boggles the mind. The bearings are from Z1 enterprises and I think I was just unlucky and inexperienced with the Z1.
the other option is that the caps are not original to the head. This would be tempting to latch on to but the motor ran well when I straightened out the carbs.
I chalk this up to a bad rookie mistake. I never thought to check the sides of the fit, just the vertical clearance with plastigauge. Also, I now know that if the shell doesn’t settle in to the saddle easily there is a problem. If it wants to snap in it’s likely going to pinch at the split. So the real test is to put the bearings and cams in with no valves installed, if it is difficult to turn, there is a problem.
Looking for a set of cams, stock if possible, or at least close to stock. I don’t want a hot rod engine.
