Hilliard Fury with 2 white and 2 black springs if you have to have it completely stock except governor removed. 4 black springs if you are allowed to modify it a little but have to have small pipe and stock airbox. 4 white springs if you have to have it completely stock with the governor intact. Works best for us generally with 2 white and 2 black springs in the stock predator classes. Or you can go to the local Tractor supply store and get a Hilliard Extreme Duty clutch, which is almost the exact same thing as the fury, and run it just like it comes in the box if you run stock predators, if you need it to engage higher, order 4 black springs. Be sure to wipe the clutch clean with WD-40 before you put it on the kart, and be sure to oil the little bronze bushing inside the drum before you use it, and after each night of racing. After each night of racing, when you take it off to lube up the bushing again, spray the entire clutch down with WD-40 and wipe it off with a rag, leaving it slightly wet so it doesnt rust. Dont try to clean it with brake cleaner, acetone, water or anything other than WD-40 or you will reduce the life of the clutch.
