well im hopeing to find out this ? soon. my buddy just built a 421 cub motor,running 39mm mikuni flat slides,+6 swinger,22 domes(pump gas-lol) and a few other things. i just got my bike back together,stock cyl.--drag ported,SHAVED head(.030) -flywheel and reed cages,34mm kein... carbs,35mm pistons,hot rod crank and a set of cpi out of frame pipes.
we are both running 9 paddle 3-buffed haulers, both under paddles on sand . he's not set up good!! im calling he'll have me by 1--1 1/2 bikes.his is a beast but he has no traction.he's suppose to be getting a 14 paddle(i think its to much). hope to run them sat.