I was at a race in New Castle, IN so I was no where near the old computer. My computer only works in Naperville. I looked at the pictures and he has too many washers on the end of the driven unit. It was meant to have some float since it is outboard mounted and it is a series 20 clutch. The oilite bushing on the driver unit is a good idea to have if the belt is tight. Once the pins in the driver unit get bent I would get new weights just because it is very difficult to straighten the pins. The cause of the problem was the driver unit wasn't on tight and it gave the weights a chance to get to far out inside the driver unit.
Series 20 and series 30 are basically the same and handle the same horse power. A series 30 is always outboard mounted, driven unit has the ramps facing you as kneel down looking at the engine. The series 30 is asymmetric which means the belt is almost flat on the side closest to the engine and it runs a lot hotter than a series 20 because the belt is being forced up the flat side of the sheave. Series 20 are symmetric which means the angle on the belt is even on both side so it as the same pressure on the belt as it goes up or down on the sheaves and will not generate as much heat. When you use a series 20 outboard mounted like the Yerf Dog the driven unit was meant to float on the jackshaft so the driver and driven would be aligned when the driver would move the belt inward. Series 20 were meant to be inboard mounted (ramps facing the inside of the unit and the name would not be visible as you knelt down looking at the engine). We made them both ways because some manufacturers didn't want to build their own jackshaft. A series 30 is much easier to mount on an engine but it WAS designed for a mini-bike. Yes, it will work on a go kart but it has it limitations and you must start compensating when you get larger on the tires, then you must think about a larger driven and more holes in the cover guard to let out the heat on even Comet belt will need some of the Yak grease.
