You're amazing truckd. You're a master builder. I'm more of a masturbator.
Amazing that these 500cc & 1000cc bikes of old didn't put out any real HP, a PK 68.5/80cc puts out 3.5 HP and with the mods I'm doing I will barely tip 5 HP I'm sure that gearing has a lot to do with it as well as boring,porting,valves,carbs amazing that a 50cc Morini can give you 9 HP.
I'll explain a bit here. The hp rating on British bikes was nothing to do with the actual output, it was a formula based on bore and stroke for road tax purposes.