Old Motor Shaft Size VS New Motor Shaft Size, Pinion and Rack...

[rb99]

I am getting around to installing a new 4g controller (I bought it a few years ago from SB) on my older strut machine. I remember when I asked about new pinions they were more expensive because they were modded to fit the old shafts. Can someone tell me if my motor shafts are bigger and/or what other differences I might find? Is the rack a different size as well?

Does anyone remember the price of new pinions verses retro pinions?

If I buy a new Z will my old motors and pinions fit the rack on the new Z? (Not the retro Z but say a used Z?)

How much are new motors compatible with the 4g controller? Any recommendations?

Thanks

[garyc]

Richard...
Depending on the motor model number Pinions are as follows:
Shaft diameters: 12mm (keyed) 14mm and 1/2" (you can mic yours to be sure)
Teeth: 20, 25, 30 tooth (18 T replaced with 20 T) (you can count these)
Rack width: 1/2" or 3/8" (earlier) (easy to measure)
There are also some earlier models that have a 14 (or 14.5) degree pressure angle in lieu of the current 20. (14 only on the 3/8 boston rack)

If you post the motor model number you may get more help.

All PRT motors will bolt up to all PRT Z assemblies