Hi Mike,
There is more to this than meets the eye. If an engine is four stroking and the ignition too retarded it can still overheat and seize.
I see your Scott is not standard with Moss head, pistons, barrel plus twin carbs. All this can well alter the ignition timing required probably it is now too advanced on standard setting. My engine has had many internal alterations plus an effective resonant exhaust system. It is a 1932 blind head 500. After all this I had to completely retune the carburettor and no way would it run on the standard advance of 35 degs any more. I set to work retarding the ignition bit by bit until I could feel it was running correctly and eventually got down to 21 degs full advance. You will not get down to this low figure but will probably feel an improvement as you retard it slightly. If you go too far it will go dead and get hot.You will need to ride the bike for a period of time to get the feel of the engine before trying this.
Regards,
Bob.
