So I've got my big bore kit all run in now but I'm not too pleased with the top end; the bottom end is much better but the top end is poor. I can only do about 65mph now whereas I could do 70mph consistantly before I installed the big bore kit, even in low gears I cannot get above 7k rpm and I could do roughly 10k before. I was wondering if the stock carb is limiting the ammount of fuel/air mix getting into the cylinder since it now needs 20% more per intake stroke, am I on the right lines here?

I read somewhere that I have a 22mm Mikuni already and the Molkt 26mm will fit right onto my existing intake boot but are there any better alternatives? I don't want one that will be hard to get the jetting right.