I'd say it's half a dozen hard-core members who contribute on here Dean, everybody else seems to treat it like a library. Look at any post and there'll be 100 plus views and maybe, maybe 2 or 3 replies. If only we could ask them lol lol
Maybe email an engine builder, someone Like vulcan and see if they can help you ? Or reliant parts world ? Or Graham walker in Chester ?
jefferdp I agree with Stiffy they ARE different. I sourced my info from a Reliant handbook, remember that Bond and Reliant were very close bed partners at the time of the Bug albeit they were separate companies, and they were using up stock from the stores.
Engine 750cc 850cc
Bore 2.46ins (62.50mm) 2.46ins (62.50mm)
Stroke 2.40ins (60.96mm) 2.72ins (69.09mm)
It is common practice in engine design to have a "Standard" casing then to bore to different sizes and the same with crankshaft throws which effects the length of the cornrod. That way you get a range of engines all using the same casting but with different performances.
For spares you should probably try some of the Reliant spare sources regards Bill D aka Ayrbugger