Re: centrifugal clutch question
the simple answer is Yes... but it depends on which type centrifugal clutch you get since there are 2 different types I know about... The most common type has a one way bearing that rides on the shaft extension and it can be pull started or bump started because the one way bearing will lock up when torque is applied from the rear wheel but free spin when the engine is running until the clutch engages. These are most commonly sold on ebay by sellers like BoyGoesFast.
The other type don't have a one way bearing but just a standard bearing on the shaft extension and requires a pull start, these are usually sold by the Grubee dealers and also need the clutch housing to be sealed off and then you add 3 ounces of oil since the friction surfaces on the clutch pads run best in an oil bath. The standard type with the one way bearing need to be run dry, just grease up the bearing and the shaft during assembly and it needs to be re greased periodically.
No need to widen the crank, these kits come with a shaft extension that goes on where the bevel gear went.