OK, I understand carb, you can bypass auto bystarter if you want, but will have to manually choke carb to start.
Why did you install 3gr and 6gr rollers? How did it run with stock 8gr? At your weight 125#, probably don't need really light weight rollers to get acceleration. When rollers are too light, trad-off is often less top speed. Engine peak torque is where you get max acceleration, speed up hill, with stock exhaust pipe peak torque is approx 7000 revs, less or more revs, engine is not working at maximum. Good luck...