Black Magic Racing did some looking into the â€˜04 and â€˜05 Arctic Cat 660 ST models and found that these sleds are not immune to engine movement. They put the sled up on a stand and in a word, â€œHOLYâ€! You wouldnâ€™t think that a motor that big would even need to be bolted down! (That was a joke). Oh yea, she moves.
They got a good feel of how the motor was moving; just like any other sled, up and back, basically trying to twist itself out of the chassis. This, as you may already know, really screws with the efficiency of the clutches, is hard on belts, and hard on the mounts and everything else that is attached.
They fashioned up a torque arm, installed it where they believed it would be the most effective, and engine movement was nearly eliminated.
In a nutshell, the T-660 4-strokes are no different than the 2-strokes. They move around, and this affects drive belt alignment, offset and center distance. Translation, we can do a better job at maintaining clutch-to-clutch distances and power transfer consistency. If you want or need a torque arm for a 660 Arctic Cat 4-stroke, Black Magic has them (218-681-1150 or www.blackmagicracing.com). Order part number #70-1471 for $59.95. Power is useless if you canâ€™t get it from the engine to the track!