Are you sure you have a 91 mdl MC18? If it is 91 itll be an MC21...
I have seen this model RS engine in MC21s before, but dont know much about the amount of work involved in getting it in etc - remember that this idea is no good for a road bike as the RS engine doesnt have a kick start.
Maybe others have more knowledge? If you start a thread on it, or do a search in here there should be some info around...
xvfrona wrote:I am in NZ, what state is the engine in and would it fit into a 1991 NC18 (without too much adjustment!!) and how much you looking for. Regards Keith