Had problems with my bike not starting and compression issues. Put a new barrel,piston& rings and also a new head. Put the cam on and made sure the timing was ok. But when I've come to the last job of adjusting my valves the exhaust valve is closed and I can't get a gauge behind it no matter how much I screw it out?! Please help. Is it my rocker arms bent? Replaced everything else apart from them and the camshaft
