Yeh these little chippers were way cheaper than that nice machine. Flywheel in them was maybe 40lbs at most. Direct drive off the gas engine, nothing to change the speed. Figure the gas engine maybe doing 3200rpm at full throttle, give or take.
As for my PTO conversion, the big pulley rode on a fixed bearing that was mounted to an adjustable plate. The plate moved up/down to set the belt tension. The shaft was just a stub shaft, it didn't pass through the machine. No doubt this is crummy design, but there was no room to pass the shaft through, it would have interfered with the flywheel. Kind of a "it's this or nothing" situation when doing a conversion.
Hadn't considered the chute angle being wrong, probably a big reason it failed. Trying to fix that wouldn't even make sense given the time/cost.