martell06 said:
can someone enlighten me as to what the numbers mean?
Hell, I worked in tire shops for 20 years and I don't know what the numbers mean. They progressively got higher as the years went on and the features grew.
As far as the "tap dance" goes...most "modern" center post changers incorporate a "feathering" feature, where the post can be controlled via foot pedal pressure. If you are halfway through the cycle, you can hold the bar in position, by releasing some pressure from the pedal. It won't advance, and it won't return as long as that level of pedal pressure is maintained.
On older models, the pedal control was more of an off/on control. It either cycled forward full speed, or it was in the return mode. Some level of control can be obtained by rapidly pressing the pedal on/off ("dancing"). Every machine has a different "feel", and familiarity with any given machine requires some warmup or practice time.
Holding the bar...this can go both ways. If one holds the bar tightly, any sudden rotation can cause painful results. On the other hand, setting the bar on the post, letting go of it, and mashing the pedal is just as bad, if not worse. I have transported at least three noob tire guys to the ER as a result. Head injuries, as I recall. Big eggs on their foreheads and shiners for weeks.
Knowing when to hold the bar or let go is a result of experience. Your hand can feel the tension, and it should communicate this through your brain to the foot on the pedal. Hard to explain, but it works.
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