The starter issue you describe I encountered after a rebuild of my big red, It seemed to kick back and was on its 3rd starter when we finally discovered the issue. It was simply the exhaust valve lash was set to loose and not letting the decompression device open the exhaust vales the little bit it was designed to do. We checked compression at starting and it was way too high (over 150 psi), I read maybe 65 was correct, mine came down to under 80 after adjusting the exhaust valve clearance to correct specs. Correct exhaust valve specs were .013 cold as detailed in the owners manual. Made all the difference in the world for just a little incorrect adjustment!!!