Someone who has more experience will be along shortly but I am pretty sure you would be ahead to swap engines (or bikes). I believe the cases are entirely different.
Even if it were possible, you would have to buy a donor engine anyway. Buy a donor motor in good shape, then either rebuild it from the ground up, or just do the top end (pistons/head).
you will find it fits right in you need to put a perch for the clutch and the oil tank must be mounted but otherwise it worked out fine on mine i had a hondamatic 1977 but a friend gave me a 750e engine as soon as i got it here i started tearing out the hondamatic i dont like the hondamatic engine very much it lacks power and is kinda unsafe at times plus it didnt have a kickstarter
The hondamatics are a sought after item. They are used quite often in bracket racing as they are dead on consistent. Anything performance wise that you can do to the std 750 can be done to the auto. All the engine parts fit. Many big bore auto's running around. IF you have a running auto you should be able to sell it quite easily.
The hondamatics are a sought after item. They are used quite often in bracket racing as they are dead on consistent. Anything performance wise that you can do to the std 750 can be done to the auto. All the engine parts fit. Many big bore auto's running around. IF you have a running auto you should be able to sell it quite easily.