First legal build

wheeliepete

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Got a sudden urge to put together a lightish 36v rear hub bike for a bit more of a workout. Got a KT 36/48v controller, pas etc. on the way from PSW Power and looking at the cassette motors on BMS Batteries. Am I right in thinking the 201 rpm 800w Q128H or 201 rpm 350w Q100H are the best choice for running 26" wheels? How do they compare in weight? Will the Q100H be happy running 20 amps?
Also do the motors come with the lead to the controller?
 
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Deleted member 4366

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All the motors come with the right lead.

Q128 is about 3.5kg, Q100 is about 2.2kg.

"H" versions are for freewheel gears. "C" versions for cassette gears.

If you want 20 amps, the Q128 would be better. Forum member Cwah ran a Q100H at 48v and 20A for a while. He's quite light, but still there was noticeable wear on the internal gears when I opened the motor.
 
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wheeliepete

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Thanks for that D8veh, I'm only around 75kg, so I might chance the Q100H. What do you think of lacing a motor into an good, but old single skin rim?
 

Nealh

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Q100 lighter use parameter C5 to reduce amps by up to 5a.
C5 & 3 will set it to 17a.
 
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wheeliepete

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I was thinking the same Nealh, can always adjust the power depending how fit I'm not feeling! like the idea of the lighter Q100H, that's nearly half the weight of my battery saved.
 
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Q100 gives a lot of torque. I used to use one when I was 100kg. At 75kg, it should be fine for you.