Where to find the right hub motor for me

[wiwild]

Hello,

I bought a bike : Oryx T-500 which is a 10kg aluminum bike.

I wanted to add an hub motor, mostly for hills, to it and for long trip.

I want something lightweight not too big. I already have a greentime controller 12 Mosfet 30A 500-600W and a 14s5p battery pack made of Samsung ICR18650 cells with a 16A constant charge/discharge BMS.

I saw on this site : https://www.electricbike.com/12-kit-power-levels-360w-to-8000w/ that my ideal motor would be a BAFANG-BPM at 960W.
So I loose regen braking but can freewheel when I don't use it.

I would like to stay under 200$CAD with shipping, that's why I was searching for used one on this forum but there isn't.

I find this http://www.greenbikekit.com/electric-motor/rear-bldc-1.html?dir=asc&order=price&p=2 but there is so many references.. I would like to achieve like 26mph with it on a 26" wheel.

Can you tell me the cheapest site or if you have one to sell.

Also I need to lace it in a 26" rim I've never done that so maybe I must have it done for me ?

Ps: I live in Canada/Quebec
PPs: My rear shifter is shimano cassette with 9 speed and I have disc brakes.
Thanks!

 

[FluxZoom]

https://bmsbattery.com/ebike-kit/351-bafang-bpm2-48v500w-rear-driving-e-bike-hub-motor-ebike-kit.html? Maybe?

P.S. : High speed means low torque. Low speed means high torque. RPM means "Revolutions Per Minute". 201RPM is often used for 24", 26", 700C and 28" rim. 328RPM is often used for 16", 20" and 24" rim.

 

[Grizzl-E]

Pm sent

 

[wiwild]

Ok so with the motor on bmsbattery that say 201RPM so, 31mph/50kmh on a 26" tire ?

Grizzl-E has some mxus xf07 but with both motor I cant fit my cassette right ?

I've found this one too http://www.aliexpress.com/item/36V-48V-250W-High-Speed-Brushless-Gear-Hub-Motor-E-bike-Motor-Rear-Wheel-Drive-MXUS/1880934447.html?ws_ab_test=searchweb201556_1,searchweb201602_4_10017_10005_10006_10034_10021_507_10022_10009_10020_10008_10018_10019,searchweb201603_6&btsid=93e295b3-65ad-4ff3-a3f1-4f86d5e9c619 by typing the reference of Grizzl-e is it the same ?

Thanks !

 

[FluxZoom]

There is a Q100c hub motor where the C stands for cassette, but I doubt you can hold a 9 speed cassette with it, maybe with spacers and a spread fork, maybe. Personally I place little value on high gear count on an electric bicycle, makes a lot of the gears worthless. Freewheels screw on, you can see the threads on hubs, you should figure out how to tell the difference if it's important to you. Cassette setups might be a little nicer but require more space, sometimes this means motors aren't as wide internally (might not be ideal).

 

[wiwild]

It's just because it's what I have so there is nothing to buy other than the motor. Also I'm sure it is compatible with my shifter.

I'll measure the space it takes.

 

[FluxZoom]

It's just because it's what I have so there is nothing to buy other than the motor. Also I'm sure it is compatible with my shifter.

Yeah, I got that, you'll probably have to change some things. Something else you may not have considered is a torque arm setup, it's probably not optional, especially on an aluminum frame. https://en.wikipedia.org/wiki/Fatigue_limit

 

[wiwild]

Ok so, I have an approximately 45mm wide cassette and a 135mm dropout. 5mm too much ? No motor are slim enough to accept a 45mm cassette ?

What is the difference between rear and front motor ?

Also I just need "pedal assist" that's why I target low power motor.

Like this one : http://www.greenbikekit.com/electric-motor/rear-bldc-1/e-bike-cassette-freewheel-hub-motor-36v-250w-light-weight-high-speed.html or this one but heavier http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2015-8X-2S8V.1T5PW

Thanks

 

[leo99]

I am doing a similar build with a Q100c and a 9 speed cassette. You can look at my thread with my signature. I have put the motor without any problems and I have put the 9 speed on the motor but I haven't tried putting the motor on with the cassette but I don't see where there would be any problem. EDIT: it fits without any problem
I will be running the motor at 14s with 15 amps. More amps would mostly likely melt the motor so I don't think know this motor would be the best maybe look at 128c who is similar but would take the amps better and has a cassette also

 

[MadRhino]

Welcome to a new Montrealer ebiker :wink:

For low power, the right motor is not hard to find: Any small motor will do.
I went to a shop and bought the only one left, and it turned out it was just right :lol:

Pedal assist is another story, I mean intuitive and natural feeling PAS is not so common. This is not about the motor, but the controller program and PAS system that are translating rider's cadence and torque. I am not really into this but I like the Bionix and I have heard that some cheaper systems are very close now.

 

[leo99]

Just in case, I checked my motor with the 9 speed and it goes in without any problem with the 9 speed installed so you shouldn't have any problem with the Q100cst or the Q128C.
I hope this might help you.
Leo

 

[wiwild]

I went to a shop and bought the only one left, and it turned out it was just right :lol:

A shop in Montreal ?

Just in case, I checked my motor with the 9 speed and it goes in without any problem with the 9 speed installed so you shouldn't have any problem with the Q100cst or the Q128C.
I hope this might help you.
Leo

Ok thanks, I read your thread nice idea to switch from 3 to 1 speed in front.

I think I'll go with this already laced Q100cst https://bmsbattery.com/ebike-kit/617-q100c-cst-36v350w-rear-driving-e-bike-motor-wheel-ebike-kit.html?search_query=q100c&results=7 about the rpm I think 201 is the best ?

Thanks.

 

[spinningmagnets]

Here's an "RPM and wheel diameter to speed chart"

https://endless-sphere.com/forums/viewtopic.php?f=28&t=16114

 

[wiwild]

Here's an "RPM and wheel diameter to speed chart"

https://endless-sphere.com/forums/viewtopic.php?f=28&t=16114

Thanks didn't see this I was using this site : https://wahiduddin.net/calc/calc_speed_rpm.htm

Which gave me wrong result or I misuse it.

So 328RPM will be more appropriate since 201rpm only give me 20kmh..

My controller is able to put 30A to the motor when torque is needed, will the motor sustain it ?

 

[leo99]

30 amps would be way too much. it is only 2kg and the q100c is even has a smaller motor mass then the q100h who barely stands 20 amps before gears brake from what I have read. As I will personally run mine at 15 amps with a controller that is 25 amps that I am going to reprogram lower to save the motor from certain death.

if you are going to use a 14s battery that means you will be running the motor at a faster speed. 328 is at 36 volts at 52 volts it equals to 328/36v * 52v = 473 rpm = 58 km/h no load so much too fast for the size of the motor. the 201 at 52v 290 rpm = 36km/h that is much more realistic for that motor.

If you really want to keep that controller you should look at a Mac from em3ev or maybe the q128 but even that one should be to small for 30 amps

that's my 2 cents from what I know
leo

 

[wiwild]

Is it possible to replace gear to metal ones ?

Do you know a place where I can fin the 260rpm version ?

Thanks §

 

[leo99]

I don't know if there are any metal gears for this model but they will make a lot of noise. The clutch has been known to have some problems with too much amps.

The 260 is only for the Q100h who has slightly bigger motor but has a freewheel. The Q100cst only comes in 201 and 328.