Good Day , I have a 350cc Merlin Cagiva which has pretty much overnight developed an engine issue. It will now not fully rev. The engine sounds muffled when revved, like if the exhaust silencer was blocked ( which it is not). I have checked the carb, cleaned the jets, tried different jets and even tried a new carb. This did not solve the issue. I checked the coil and tried a new coil. This did not solve the problem. I checked the stator and tried various advance and retard positions. This did no