I can't find the number on the engine I have! Not on the diagonal flat from the bell housing nor next to the breather! All I have is the letters AP on the flat bit next to the breather
Me thinks its been filed off........
There are normally 2 numbers, one next to the coil on the fan housing and the other (same No.) behind the breather on the crankcase.
AP stands for 1800cc but it looks like someone has taken the No. off. The factory recycled motors also had 3 arrows in a circle to identify them.