Q128H

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Deleted member 4366

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#1
About 3 years ago, after a lot of success with the Q100 motors, I tried a Q128, which is bigger, so I thought it would give a lot more torque. It was a total disappointment. I don't know why, but it was gutless regardless of how much current I pumped through it.

The Q128H has been around for a while, but I never heard of anybody trying one, so, to satisfy my curiosity, I had to get one. To go with it, I got one of those 09 flat bottle batteries that includes a 20A sinewave controller and the rest of the kit. I lashed up the kit to an old Carera Kraken I had lying around, and was finally able to satisfy my curiosity. This is a 48v system and the motor is the 201 rpm version.

The previous one I had was quiet, but this one is very quiet and smooth - almost silent. Nobody will hear you coming. The Torque is impressive. . It had no trouble dragging me up our 14% test hill without pedalling. In fact, it could stilĺ get up at half throttle. It seems to be very happy giving high torque while going very slowly. It would therefore be very good for heavyweight people who want a lightweight bike and aren't too bothered about speed or maybe for towing a trailer. The throttle is very soft. It's dead easy to trickle along at 2 or 3 mph.

It comes with a label that says 800w on it. If you pealed it off, you wouldn't have any trouble convincing people that it's a 250w motor. It's much smaller than a Bafang BPM.

I'm not too sure what the top speed is yet. 201 rpm is 15 mph. I don't think that it's much faster than that, though if you want more speed, you could always use the 36v one at 48v. I haven't managed to get the PAS working yet, nor the speed display. I've got a feeling that there's a fault in the controller or display. I'll have a go at sorting it tomorrow. The last one of these kits I used worked perfectly straight out of the box. For that kit I used a 500w BPM motor. This one has the same torque, though the BPM had more speed, but was noisier.

I'll try and post some photos when I've finished it.
 

anotherkiwi

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Jan 26, 2015
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#2
Is there space for a controller in a "normal" flat bottle battery case? Is it possible to take off the controller's aluminium casing to make it fit if it is too large with the casing?

Sorry, more questions to come I am sure...

Tony
 
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Deleted member 4366

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#3
No. It's a special controller made to fit in the base of the battery and it uses the bottom plate as a heatsink. You can buy the controller kit on its own. You get the controller, waterproof harness, LCD, throttle, PAS, ebrakes, motor adaptor wire and motor extension wire for £72 including shipping.

https://bmsbattery.com/controller/698-sine-wave-controller-for-09-case-controller.html

The motor wires are both very long, so you need to cut and join them somewhere unless you want miles of wire wrapped around your battery. Whichever ones you cut, you only need one join.
 

awol

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Sep 4, 2013
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#4
How do you get the shaft on there to fit my 8spd cassette cogs if I fancy trying one in the future?
 
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#5
It's a freewheel motor, so you need a 8 speed DNP freewheel gear-set. You need a fairly substantial dish in the wheel to get the rim central. It didn't take much springing to fit in my 135mm frame. Maybe it was already stretched a bit. The motor's 145mm, wide with the 8-speed.
 

anotherkiwi

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Jan 26, 2015
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#6
No. It's a special controller made to fit in the base of the battery and it uses the bottom plate as a heatsink. You can buy the controller kit on its own. You get the controller, waterproof harness, LCD, throttle, PAS, ebrakes, motor adaptor wire and motor extension wire for £72 including shipping.
Is the PAS connector on the controller compatible with a torque sensor? Is the PAS connector on any controllor compatible with a torque sensor or do I need a torque sensor specific controller?

Sorry for being slightly off topic

Tony
 
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Deleted member 4366

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#7
Look at the BMSB website. They do a torque sensor version. Personally, I think that a decent PAS sensor is more than adequate. These controllers have very nice power algorithms, which mean that there's not really any advantage of a torque sensor.
 
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#9
Go to the BMSB website. Add it to your basket. Check out and you will see it's £72. Simples!

The controller uses current control, so selecting a lower level reduces the current; however, you get the full 20A with the throttle.
 

jonathan75

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Apr 24, 2013
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#10
A US$43 charge bumped it up for me to US$130, ie £84! Are you getting mates rates or something? ;)
 
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#11
What's the $43 for?
 

awol

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Sep 4, 2013
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#12
Any idea how it's weight and torque compares to a bafang CST 250w ?
 
D

Deleted member 4366

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#13
At 20A, it has more torque and it weighs about 1kg less.
 
D

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#15
I get $25.88 shipping to uk.
 

jonathan75

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Apr 24, 2013
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#17
I solved the mystery of the two different prices you and I are getting. When logged into the BMS site via the account I set up with them, shipping prices are much lower. Though they do strangely 'jump' by $10 sometimes when one puts an extra $1 item into one's basket.
 

awol

Esteemed Pedelecer
Sep 4, 2013
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#18
It comes with a label that says 800w on it. If you pealed it off, you wouldn't have any trouble convincing people that it's a 250w motor. It's much smaller than a Bafang BPM.
Who is the manufacturer, if I were to make a replacement power label I would need to put that on, do I now need to include the max speed cutoff of 15.5mph on there too?
 
D

Deleted member 4366

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#19
I believe the motor to be a clone of an Aikema motor. It coild be a genuine one, but Aikema didn't know who BMSBattery are. BMSBattery's main office is under the name Ecitypower, so that doesn't mean much.

I think the Ideal label would have the following info on it:

AIKEMA(AKM) Electric (Suzhou) Co., Ltd.
36v
250w
Max speed 25km/h
EAPC
CE mark

After further testing of my 48v 201 rpm Q128, I can now say that itgives good power to 17 mph, which then tails off to zero power at 20 mph, so if you want a bike that's restricted to 25 km/h, but gives very high torque. This combination of motor battery and controller is the one. It'll blitz all the OEM bikes with BPM/CST, Ezee and Bosch
Motors in a hill-climbing contest. You would get similar power from a BPM at 48v and 20 amps, but the Q128 is smaller, lighter, smoother and quieter. Somehow, I'd always thought that this motor would be a hidden gem.
 

trex

Esteemed Pedelecer
May 15, 2011
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#20
which controller do you use with this Q128H? their test report looks very impressive against the BPM.

q128h.jpg
 

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