Thanks for the replies. I will be using the bike on the road, mostly riding with a group of British bikes that are faster. I think I will go for the 90mm bore. I am thinking standard cams with maybe 2mm extra lift. A bit larger valves, particularly the inlet. Radius the valve side of the barrel. Machine the head down as much as practical. Would that sound sensible?
Ian, I see on another post that you have had some pistons made. Would any of these be available? It would simplify things.
