Hi,

Yesterday I found out that my new second hand engine from a '91 750 ss was stricktly air cooled. There is no casting around the cilinder to hold oil as on a 750 sport. The early 750 ss versions even came without a oil cooler (it was an option). I found out reading some literature. In noticed on a later post '91 750 ss engine that it has the oil castings on the cilinder.

So:
750 sport air/oil cooled
750 ss (91) air cooled
750 ss (92+) air/oil cooled

I also notice that the dowels in the oilway are sligthly different. The 750 ss has larger diameter passage compared to the 750 sport. I suppose this has something to do with the cooling (mass flow vs pressure?)

I was wondering what the interchangeability would be between the engines and there cilinders? Could a strickly aircooled set-up be installed on 750 sport lump? As far as I can tell there is no difference on the mating surfaces between the cases, cilinders and head. Could there be a difference in the oil-pump?

The heads differ slightly as the 750ss has a spherical combustion chamber.

Did some more reading and found that also the 750 sport came with either air cooled or oil/air cooled engines.


Kind regards,