Q128H

[Deleted member 4366]

It doesn't work like that. If you only had level 3, you'd get maximum power every time and as soon as you pedal, which makes an uncontrollable bike when the motor is a high torque Q128H.

If uou only have level 1, it wouldn't be fast enough. Level 2 is too much for going slowly, and too slow for when you want to go fast. When you have all three, you can go fast and slow when you want. 5 levels from a LCD are even better. For high torque motors and crank-drive motors, current control is better. You only get that from modern controllers with LCDs.

 

[tongxinpete]

So you make adjustments to the LCD power setting as you ride - dependent on the type of terrain? a bit like changing gear on a bike
I found this Con92 - it is said to have a soft start built in. I tried adding to cart to see if there was an option for an LCD display, seems not.
Is the soft start an alternative answer to the problem of the Q128H being aggressive during the start from standing you warn about?
Elifebike have a wide range of controllers (with LCD an option)
They do not though mention soft start.

Soft start controllers exist for industrial motors - they are used for limiting the starting current load before self limitation (the back emf) kicks in as speed increases. One was put on a large pump in a very rural area - on the end of a long line (hence called by the MEB as a soft supply) Problems went away

 

[1boris]

A new CST version.Now I just have to buy one


https://bmsbattery.com/ebike-kit/768-q128c-135mm-500w-rear-driving-ebike-hub-motor-ebike-kit.html

 

[awol]

A new CST version.Now I just have to buy one

Typical they just released that, I couldn't resist and bought a Q128H a few months ago to try and built this up to try and am very impressed. Smaller/lighter than my Bafang CST, just lower rpm but with similar torque.
The other good thing about that new CST version is the dropout width of 135mm whereas the Q128H is 145mm which I didn't give a secong thought to at the time so requires a bit of an extra 'heeve hooww' to get into my dropouts.

 

[1boris]

Typical they just released that, I couldn't resist and bought a Q128H a few months ago to try and built this up to try and am very impressed. Smaller/lighter than my Bafang CST, just lower rpm but with similar torque.
The other good thing about that new CST version is the dropout width of 135mm whereas the Q128H is 145mm which I didn't give a secong thought to at the time so requires a bit of an extra 'heeve hooww' to get into my dropouts.
View attachment 12387

The CST version is "only" 500w.But there is a new 800w version,not cst but 135 mm.
Is your motor 201 rpm? Are you running it at 36v or 48v .Whats your top speed?
I am curious since I am waiting for the new 800w 135mm version (201 rpm at 36v) with a battery pack with 48v and 18 amp controller

 

[awol]

The CST version is "only" 500w.But there is a new 800w version,not cst but 135 mm.
Is your motor 201 rpm? Are you running it at 36v or 48v .Whats your top speed?
I am curious since I am waiting for the new 800w 135mm version (201 rpm at 36v) with a battery pack with 48v and 18 amp controller

I got the 36v 201rpm.I am only a light person and running it at 36v 16a
I got about 17mph ish and at 12s-44v I got about 21mph although my speed is usually restricted anyway so its fine for me at 36v.

 

[Deleted member 4366]

My 48v 201 rpm one does 19mph with a fully charged battery. What I want to know is the actual speed of the 36v one at 48v. Extrapolating your results, it would be 13/12 x 21 = 22.75 mph. My one's torque at 20A and 48v is immense for such a small motor. It's max efficiency of about 80% at 12mph would give it an output power of 770w at that speed, which is enough to climb even steep hills.

 

[1boris]

The new Q128H motor 800w 135mm in a 26" wheel does 52kmh unloaded and about 44 kmh loaded on the flat with throttle only.This is with a 48volt battery and 18ap controller
https://bmsbattery.com/ebike-kit/776-q128h-48v800w-rear-driving-e-bike-motor-wheel-ebike-kit.html

 

[anotherkiwi]

Clean build!

 

[delboy55555]

View attachment 12526 View attachment 12527 View attachment 12534 The new Q128H motor 800w 135mm in a 26" wheel does 52kmh unloaded and about 44 kmh loaded on the flat with throttle only.This is with a 48volt battery and 18ap controller
https://bmsbattery.com/ebike-kit/776-q128h-48v800w-rear-driving-e-bike-motor-wheel-ebike-kit.html

Which freewheel do you have on there? How many gears?

 

[1boris]

The freeweel is 10 and orderet from em3ev.com But there are some problem with some of the gears

 

[delboy55555]

The freeweel is 10 and orderet from em3ev.com But there are some problem with some of the gears

10 speed and it fitted ok in a 135mm wheel? I wonder if a 9 speed might work better. Im trying to decide between this and the new q128c but that one is 500w so finding it hard to decide now!

 

[1boris]

Fitting was no problem,even the spokes was tight and didnt need any adjustment or dishing.I didnt build the wheel,ordered it from bms battery and put it right on the bike without any adjustment.But I think the space between the gears are not matching the orginal XT gears and thats why some of the gears have trouble.This motor only come in one winding and it is listed as 36v and 200 rpm.That is wrong because I can pedal the bike close to 50 kmh.So the winding must be around 270 rpm at 36v.But even with the high speed winding with a 48 volt battery an 18 ah controller it is really strong on hills and does not seem to have any heat problems.and i am 105 kg.Very impressed with the motor so far.The cst has less space inside because of its cst build.the stator is not so wide as the one at 800w.you can read about it and ask questions here:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=72094

 

[delboy55555]

Fitting was no problem,even the spokes was tight and didnt need any adjustment or dishing.I didnt build the wheel,ordered it from bms battery and put it right on the bike without any adjustment.But I think the space between the gears are not matching the orginal XT gears and thats why some of the gears have trouble.This motor only come in one winding and it is listed as 36v and 200 rpm.That is wrong because I can pedal the bike close to 50 kmh.So the winding must be around 270 rpm at 36v.But even with the high speed winding with a 48 volt battery an 18 ah controller it is really strong on hills and does not seem to have any heat problems.and i am 105 kg.Very impressed with the motor so far.The cst has less space inside because of its cst build.the stator is not so wide as the one at 800w.you can read about it and ask questions here:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=72094

Ok thanks for the information i will check out that link also! It sounds like a great motor. Thats good you didn't have to do anything with the wheel too, I read some people where having problems with built wheels from china.

 

[Man]

So,in comparation with a bpm 500w,its the same torque without heat issues?sounds really good.

 

[1boris]

I cant copare it directly to a BPM.But the torque is maybe better at low speed.but I have tried it on some very steep off road mountain hills here in Norway.Off course it could not go on for ever up theese hills.But it wasnt any more hot than my bafang bbs 48v 750v on the same hill-It is a very nice motor.But remember I have only tried the Q128 800w 135 mm version.I can not speak for the q128c 500w version

 

[Man]

Im very curious about this motor,for the price and weight looks a really good option.you use it with 36v 22amp controller?

 

[J'adoreParis]

My Q128C, ready built into a 20-inch wheel, just arrived, but when placed in the dropouts, it doesn't spin freely by hand. Is this normal for a new motor?

 

[Marc Webster]

Fitting was no problem,even the spokes was tight and didnt need any adjustment or dishing.I didnt build the wheel,ordered it from bms battery and put it right on the bike without any adjustment.But I think the space between the gears are not matching the orginal XT gears and thats why some of the gears have trouble.This motor only come in one winding and it is listed as 36v and 200 rpm.That is wrong because I can pedal the bike close to 50 kmh.So the winding must be around 270 rpm at 36v.But even with the high speed winding with a 48 volt battery an 18 ah controller it is really strong on hills and does not seem to have any heat problems.and i am 105 kg.Very impressed with the motor so far.The cst has less space inside because of its cst build.the stator is not so wide as the one at 800w.you can read about it and ask questions here:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=72094

I know I am resurrecting an old post here but I have a quick question. I see people here using the 36V Q128C 201RPM with the 48Volt shark pack with integrated 18amp controller and I want to buy this exact setup, but was told that the 18amp controller was too small for this setup. Seems people here are doing it. Curious if I can get some feedback on this. Also bike is a 700C commuter and I weigh 105kg but i do plan to pedal all the time with a PAS installed. I am not a fan of the larger 09 battery with 20 amp controler and would prefer the shark pack with 18amp if it was suitable.

I am open to any advice and suggestions.

Best regards,

Marc

 

[Deleted member 4366]

It'll give 60% more power than an average legal UK OEM ebike with a hub motor. That should be plenty of power.