Motor RPM rating = Maximum?

johneb

Pedelecer
Aug 3, 2013
88
3
Am I correct in assuming that the RPM quoted for geared hub motors is the maximum rate at which they can turn the wheel they drive? I'm considering the Q128H for my HPV Scorpion (20" Wheels) and want maximum torque for hill-climbing. Whilst I'm not particularly bothered about speed, I do want to achieve the legal assisted maximum (yes - I know the motor is well over the legal power rating). The Q128H comes in 201 rpm and 328 rpm versions, which I calculate translates to maximum driven speeds of 11 mph and 18 mph respectively, making the 328 rpm version the one to go for?
 
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Deleted member 4366

Guest
The 328 rpm one is correct for a 20" wheel. it will give a top speed of around 21 mph in a 20" wheel with a fully-charged battery.

You might find that it's a bit fierce for a 20" wheel unless you're a heavyweight. for most people, the Q100H would probably be better.
 
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anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,845
5,785
The European Union
For 20" yes the high rpm one. I have almost decided on the Q100C to keep the weight down, I feel it is sufficient to climb within the legal limit with a 26" wheel. I am going to be using a Patterson Metropolis drive and the Sunrace 11-40 8 speed cassette so an interesting range of gear inches and it spins out at about 60 km/h.

Ps d8veh Beat me to the post button! :D
 
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