Author Topic: 902 Rear Hub Motor Gear Ratio  (Read 1546 times)

Offline johnbear

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902 Rear Hub Motor Gear Ratio
« on: November 23, 2021, 01:01:10 AM »
Hi All,

I am programming a KT controller and need the gear ratio. Does anyone know what it is?

Thanks

John

Offline Bikemad

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Re: 902 Rear Hub Motor Gear Ratio
« Reply #1 on: November 23, 2021, 07:28:49 PM »
Hi John,

I don't know exactly how many teeth there are on the inner and outer gears (Sun and Annulus) but from the pictures I've seen I would estimate the gear reduction to be somewhere between 4:1 and 5:1.
I presume this setting is only required for speed calibration of the display unit, so you may have to alter it slightly if the speedometer/odometer reading does not match the GPS measured speed/mileage on your phone.

Alan
 

Offline johnbear

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Re: 902 Rear Hub Motor Gear Ratio
« Reply #2 on: December 01, 2021, 12:36:25 AM »
Thanks - I appreciate the answer. I tried 5:1 - 20 magnets. It was a bit low and would stop reading speed when there was no power to the motor. I soldered wires to the white, red and black to an external speed sensor and that worked perfectly. I really like the KT-LCD3 as it gives lots of options for the controller.  I had to take the motor off because the screws on the side were loose so I took some photos.