Thanks for the forums suggestions the over heating problem was fixed.<br />Now on inspection of the carbs I found that the butterflys were set to open half way. I adjusted the settings and gained 1000 rpm. The advance and retard settings that are attached to the throttle arm was not adjusted and so it is still set at the half throttle settings. The question is since I have adjusted the carb do I have to adjust the advance and retard settings to allow for the increased fuel flow? It is still not reaching maximum revs.