Q128H Light & Torquey 800W Hub Motor

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tomtom50   100 W

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Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 22 2018 1:24pm

After a long search for hub motors that are light, good for climbing hills, freewheel easily, and inconspicuous, three stood out:

Q100H (Aikema, sold by BMS Battery & topbikekit)
Q128H (Aikema, sold by BMS Battery & topbikekit if you ask)
Xiongda XD 2-speed (sold by manufacturer and Luna)

As with so many ebike motors it was had to find good specifications and details. That is what this thread is for, to collect and post the best information I can find or measure myself.

The impression I get is that all three motors were more popular a few years ago, but lately mid-drive and direct drive hub motors are more popular. I have a TSDZ2 mid-drive ebike, it works great, mid-drive is great. But it isn't as light, or as inconspicuous, and it has a lot of drag so that on flat pedaling without assists the drag is obvious. I'm looking to make an ebike that feels like a regular bike as much as possible. I am sticking with rear hub motors because climbing a hill a front hub motors spins. That won't do in Seattle. Finally, freehubs are great, but now that you can get good (Sun race) 10-speed freewheels I prioritized motor performance. All three hubs are available with a 135mm axle so you can build up a regular road bike (Luna only sells 145mm Xiongda, but 135mm is available from Xiongda direct).

In the end I bought a Q100H and a Q128H, and I am building the Q128H.

Here are the basics for these Aikema motors:
There is a Q100 and Q100H, Q128 and Q128H. The H models have more torque but are freewheel body only and the rpm choices are limited. But torque is a lot higher.

They have been sold for years by BMS Battery, lately I have found topbikekit who also sell them.

Both BMSBattery and topbikekit have good prices but shipping is DHL and pretty expensive. Opinions vary on BMSBattery. My experience is that they are OK but not expert. Results are better if you keep your order simple. My single order to topbikekit went well.

I know the motors are made by Aikema because the Q100H had an Aikema label underneath the BMSBattery label, and because the part numbers begin with AKM

They have double reduction planetary gears, so the gear reduction is high. This is why they are lighter than direct drive hubs, a high spinning motors geared down for torque is a lighter approach. They have higher reductions than most other geared hubs as well.
Q128H & Q100H Aikema.jpg
Weight of what you see in the picture:
Q128H: 2806g
Q100H: 2240g

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Q128H Dimensions

Post by tomtom50 » Nov 22 2018 1:29pm

Before I bought I could not find solid or consistent dimensions for the 135mm axle Q128H. But now I have it and have measured it directly, so here are good numbers to calculate spoke length:
Q128H measured 2.png

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Re: Q128H Light & Torquey 800W Hub Motor

Post by neptronix » Nov 22 2018 1:35pm

Nice thread, but you missed the Bafang g310, which is rated 500W but realistically can do 700w continuous for a long period of time and only weighs 5.6lbs and has very low freewheeling drag and high efficiency.. ( peaks in the 85% range )
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: Q128H Light & Torquey 800W Hub Motor

Post by neptronix » Nov 22 2018 2:01pm

However, the Q128H could be fun on high volts. Although the last efficiency graph i saw on it ( BMSbattery removed it shortly after ) revealed efficiency in the low 80% - high 70% range. So it can only be pushed so far due to thermal limits.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Q128H Motor Curves

Post by tomtom50 » Nov 22 2018 2:02pm

Ahh, motor curves. As an engineer I love them, but I recognize they are forbidding unless well explained, and is the data reliable.

The only Q128H motor curve data I found was in a Pedelec.uk forum:
q128h pedelecs uk.jpg
http://www.pedelecs.co.uk/forum/threads/q128h.20980/

(good thread, BTW) (D8VEH, a prolific and knowledgeable poster both here at Pedelec, used and loved the Q128H. At Pedelec UK he quite, his posts now show Deleted Member 4366).

The Torque scale wasn't marked, but I figured it out from the table at the bottom.
q128h pedelecs uk 63N-m.png
Being an engineer I wanted data, so I used the online web plot digitizer:
Q128H Motor Curves.png
The original chart went to 63N-m, I straight-line extrapolated to the stalled (End) datapoint in the data. The data was run with a 36V motor, 48V amperage is calculated assuming 48V motor performance is the same (either by different winding or gear reduction).

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 22 2018 2:47pm

neptronix wrote:
Nov 22 2018 1:35pm
Nice thread, but you missed the Bafang g310, which is rated 500W but realistically can do 700w continuous for a long period of time and only weighs 5.6lbs and has very low freewheeling drag and high efficiency.. ( peaks in the 85% range )
Thanks!

I saw the G310 at ebike.ca
https://www.ebikes.ca/shop/electric-bic ... laced.html

The rpm they show (8.4 rpm/V, 306rpm on 36V, 408V on 48V) seems too high to get me up the hills I need to climb.

I could not find a standard format motor curve chart (torque as the X axis), but using the ebike.ca simulator I get this for the 1 mile 8% grade hill on my commute:
G310 52V.png
G310 36V.png
I think I would burn the motor. If they had a slower wind it would have made the short list.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by neptronix » Nov 22 2018 3:02pm

Yikes. The motor is current limited and out of it's efficiency window in both situations. Bump the controller up to 40A to see what it's really going to try to pull.

A slower winding would be ideal. The 700c wheel isn't helping either.

If you have to take hills like that, it may very well melt the slower Q128H too.

You can adjust the kV of the bafang g310 in advanced to get a closer to apples vs apples comparison to the Q128H, except you should consider that the G310 is a lot more efficient with an equivalent kV, thus if the G310 gets scalding hot, the Q128H is already a puddle of molten metal.

Depending on how long this 10% climb is.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 22 2018 4:54pm

neptronix wrote:
Nov 22 2018 3:02pm
Yikes. The motor is current limited and out of it's efficiency window in both situations. Bump the controller up to 40A to see what it's really going to try to pull.

A slower winding would be ideal. The 700c wheel isn't helping either.

If you have to take hills like that, it may very well melt the slower Q128H too.

You can adjust the kV of the bafang g310 in advanced to get a closer to apples vs apples comparison to the Q128H, except you should consider that the G310 is a lot more efficient with an equivalent kV, thus if the G310 gets scalding hot, the Q128H is already a puddle of molten metal.

Depending on how long this 10% climb is.
The climb on my commute is 8% for 1 mile. I climb it with the TSDZ2 at 8mph, it takes 7.5 minutes. The motor case is perhaps 130F at the top. The TDSZ2 handles it fine, but it goes through the bike gears so the motor is at an efficient rpm.

Adding amps doesn't help
52V 40A Controller.png
The wind is too fast.

The Q128H is a 201rpm wind. 12 mph (climbs the hill in 5 minutes) is 146 rpm. That's where the slow winding and high power of the Q128H help out. At 146rpm efficiency is about 73%, and 50N-m of torque is available with 35N-m needed to climb the hill, so there is a safety factor. I'll find out, but the numbers say it should work. It won't go as fast on the flat, but it is the hills where I need assist.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by motomech » Nov 22 2018 5:06pm

I am sticking with rear hub motors because climbing a hill a front hub motors spins.
That is a rather general statement, but yes, a frt. mount hub motor will spin given enough power, somewhere around 1500 Watts system power. But that is the range where other handling and safety issues arise. I had a Q100H frt. mount run on a Lyen 22 Amp Mini-Monster and 14S LiPoly(Nom. 52V) and while it required some care, like having the frt. whl. pointing straight before stabbing the throttle, it wouldn't spin the whl on any hill if the pavement was dry. Suffice to say, whl. spin on dry hills is not the limiting issue, it's other things. Since most of us recommend limiting frt. motor systems to around 1000 Watts for drop-out insurance, the whl. spin when climbing is a non-issue.
Here are the basics for these Aikema motors:
I believe that right now, the standard Q100's are still made by Ananda, the original manufacturer from 2010 to the second variant of the Q100 C (the V2, is you will). They were both of good quality and that now the H's have super-ceded the Standard models, I guess they are, by de-facto, made by Aikema.
There is a Q100 and Q100H, Q128 and Q128H. The H models have more torque but are freewheel body only and the rpm choices are limited. But torque is a lot higher.
All hub motors are, to a degree, a compromise of road speed and climbing ability and any discussion of mini motors should would be amiss to not focus on the relationship of motor speed range, whl. size and system power. There are three ranges;
1)Low-speed or the "201"(that is, 201 rpm when rated at 36 Volts).
2)Mid-speed or the "260".
3)High-speed or the "328".
For reasons too lengthy to go into here, I will make a flat statement that has been proven over and over again;
95% of all mini hub motors used in whl.s 24" to 27.5", should use the Mid-speed range motor(260). Only the most dedicated riders on road bikes should consider the 328 in a big whl.
And yes, the Q100C is not available in the mid-speed range and myself(and others)have loooked into what it would take to install 260 gears into a 100C(the Holy Grail of mini's). But for most, it is a better option to use a Q100H (260) w/ a free wheel rather than a Q100 C (328) w/ a cassette. For riders who would be happy w/. a low 20's mph top speed, a Q100C (210) in a 26" or larger whl. run a 52 Volts is a good option.
The Q128 does offer a "C" option in a mid-speed range. The Q128 328 rated @ 48 Volts is, in fact a 260 version were it rated @ 36 Volts. This is a big attraction to me.
The biggest down-side to these motors is a function of their biggest attraction, their form factor. Their sm. diameter, but wide motor cores and resultant housings, can create fitment problems. The ramped side covers often end up very close to brk. caliper mounting bolts and spoke heads. In fact, the MXUS mini, sized between the Q100 and the Q128, have the factory built wheels using all "Inner" positioned spokes to maintain clearance. The C versions having the motor cores basicly "pushed" over to create the needed length for the cassette spline require extreme dishing. On some bikes the chain-stay shape/drop-out location can create challenges and it's impossible to know how things will line up until tried on a certain bike.
Motomech '11 Motobecane Fathom team, Q100H 201 frt. mounted, 14S Multistar LiPoly, elifebike 9-FET 20A controller. Mean Well HLG-320H-54A, Crazy Bobs on Alex DM32's 21 to 22 MPH.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by neptronix » Nov 22 2018 5:15pm

Yeah, 52v is absolutely not what you want to run on a mid speed winding up a hill because it will try to draw more current than it can take, and if you don't give the current, it falls out of it's efficiency band and overheats even quicker.

The Q128h might melt faster despite it's lower speed winding because of the lower efficiency. On the flats, at 800W it almost has to shed 200W of heat, which many mid sized DD motors can't even do. The picture is even worse on an 8% grade.
This is why your mid drive handles it with stride; it's correctly geared for the job.
The only way to overcome this with a hub is to have more motor than you need on the flats - some headroom for hill climbing.

Whatever you do, it's going to take a lot of watts to go up an 8% grade.

Even a 12T MAC ( their slowest wind ) threatens to get roasty toasty on this hill on just 36v in a 700c wheel, but can just barely pull it off. 700c wheels are a huge disadvantage and require more motor to overcome combination of slower RPM and high load.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 22 2018 5:48pm

motomech wrote:
Nov 22 2018 5:06pm
I am sticking with rear hub motors because climbing a hill a front hub motors spins.
That is a rather general statement, but yes, a frt. mount hub motor will spin given enough power, somewhere around 1500 Watts system power. But that is the range where other handling and safety issues arise. I had a Q100H frt. mount run on a Lyen 22 Amp Mini-Monster and 14S LiPoly(Nom. 52V) and while it required some care, like having the frt. whl. pointing straight before stabbing the throttle, it wouldn't spin the whl on any hill if the pavement was dry. Suffice to say, whl. spin on dry hills is not the limiting issue, it's other things. Since most of us recommend limiting frt. motor systems to around 1000 Watts for drop-out insurance, the whl. spin when climbing is a non-issue.
Here are the basics for these Aikema motors:
I believe that right now, the standard Q100's are still made by Ananda, the original manufacturer from 2010 to the second variant of the Q100 C (the V2, is you will). They were both of good quality and that now the H's have super-ceded the Standard models, I guess they are, by de-facto, made by Aikema.
There is a Q100 and Q100H, Q128 and Q128H. The H models have more torque but are freewheel body only and the rpm choices are limited. But torque is a lot higher.
All hub motors are, to a degree, a compromise of road speed and climbing ability and any discussion of mini motors should would be amiss to not focus on the relationship of motor speed range, whl. size and system power. There are three ranges;
1)Low-speed or the "201"(that is, 201 rpm when rated at 36 Volts).
2)Mid-speed or the "260".
3)High-speed or the "328".
For reasons too lengthy to go into here, I will make a flat statement that has been proven over and over again;
95% of all mini hub motors used in whl.s 24" to 27.5", should use the Mid-speed range motor(260). Only the most dedicated riders on road bikes should consider the 328 in a big whl.
And yes, the Q100C is not available in the mid-speed range and myself(and others)have loooked into what it would take to install 260 gears into a 100C(the Holy Grail of mini's). But for most, it is a better option to use a Q100H (260) w/ a free wheel rather than a Q100 C (328) w/ a cassette. For riders who would be happy w/. a low 20's mph top speed, a Q100C (210) in a 26" or larger whl. run a 52 Volts is a good option.
The Q128 does offer a "C" option in a mid-speed range. The Q128 328 rated @ 48 Volts is, in fact a 260 version were it rated @ 36 Volts. This is a big attraction to me.
The biggest down-side to these motors is a function of their biggest attraction, their form factor. Their sm. diameter, but wide motor cores and resultant housings, can create fitment problems. The ramped side covers often end up very close to brk. caliper mounting bolts and spoke heads. In fact, the MXUS mini, sized between the Q100 and the Q128, have the factory built wheels using all "Inner" positioned spokes to maintain clearance. The C versions having the motor cores basicly "pushed" over to create the needed length for the cassette spline require extreme dishing. On some bikes the chain-stay shape/drop-out location can create challenges and it's impossible to know how things will line up until tried on a certain bike.
Front wheel spinning. When climbing steep hills my front tire skitters sideways. Pulling a trailer it lifts off the road if I'm not careful how I pedal, causing balance problems. In short I already have trouble slipping my front tire, no way will it pull me up a Seattle hill in the rain.

Q100H manufacturer: I saw the outlines of a label under the BMSBattery sticker on my Q100H bought a month ago. I carefully peeled it back, and... it was covering an Aikema label.

Speed. Since I am fitting a climber I need a low speed wind motor. The 48V Q128H is nominally 201 rpm. That motor is also available in 201 rpm 36V wind that at 48V would be 268 rpm. D8VEH rode this combination and felt it hit a sweet spot. I almost went that way, but I look at the hills around here and decided to be conservative.

Thanks for the thoughts.

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Q128H & Q100H are Aikema motors

Post by tomtom50 » Nov 23 2018 1:31pm

In various posts it is not completely clear what company manufactures the Q100H & Q128H. It is possible in the past there were other manufacturers.

Here is some solid evidence the current manufacturer is Aikema
http://www.aikema.com.cn/En_Product.asp ... for%20rear

I bought a Q100H from BMS Battery about a month ago. It has a BMSBattery label, it looked to me like the BMS label was applied over another label, so I peeled back the Aikema label and;
Q100H Aikema Label.jpg
Aikema uses AKM as the start of their model numbers, here is the model number on that same q100h HUB:
Q100H Part Marking.jpg
(the damage on the hub is my fault, I dropped it)
I also bought a 48V 201rpm Q128H from BMSBattery. It shows no sign of a label lurking under the BMS label, but here is its part marking, AKM as well:
DSC00336.jpg
I took the 48V 201rpm Q128H apart to check its gear reduction, I'll post that soon with pictures. Has anyone seen a specification for reduction ratio for a 48V 201rpm Q128h? I'm curious to see if it matches what I measured.

Final bit of evidence, topbikekit.com.

I found this site recently, I see no sign on the forums that it is well known. They have a lot of merchandise and good prices, and they sell AKM motors, including the AKM-100H (and their picture of the AKM-85SX has an Aikema label)
2018-11-23.png
http://www.topbikekit.com/akm100h-36v35 ... p-677.html
They will sell the AKM-128H on request.
They seem to be a good supplier, I made an order and received everything promptly. Particularly nice was the 9 MOSfet 22A sine KT controller integrated into a Hailong battery base.
http://www.topbikekit.com/kt-36v48v-9mo ... p-712.html

I've seen this nowhere else, I have seen no mentions on the forums. I posted details on the KT open source thread
https://endless-sphere.com/forums/viewt ... 0#p1426374
KTE-9S5-J5.jpg
It looks like a good match for various geared hub motors, especially when a goal is a neat build.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by motomech » Nov 23 2018 11:44pm

You can save yourself a lot of time and just do a proper search here. Just search the posts of either myself, D8veh or chas58 using the keyword Q128. Literally hundreds of posts like;
https://endless-sphere.com/forums/viewt ... h#p1235123
https://endless-sphere.com/forums/viewt ... h#p1088658
https://endless-sphere.com/forums/viewt ... 28#p614826
https://endless-sphere.com/forums/viewt ... 28#p837074
And that's only a sm. sample.
You can go back to the original Q100 in 2010(when I bought my first one)by searching the posts of cellman using the searchword cute.
There really is not anything not known about these motors except why the "H" and the "new Q128" makes more power than the standard/older versions(although not the 30% BMS Batt. claims, both Dave and I think it's more like 10 to 15%). Personally, I think it's better Neo magnets.
It really doesn't matter who makes them asides from of couple of gear-sets, neither BMS Batt or the manufacturer sells parts for these things. But the beauty of these motors, they are so inexpensive a replacement can be installed and leftover can be canniblized. I've had over a half dozen Q100's over the years.
You might want to look at the 2WD bikes both Dave and I built. I built the first one, then he copied it. Then we both tried different motor speed combos, 201's, 260's and 328's. I even "mixed and matched"(didn't work well). The Q100H (260's) worked the best(best climber) and I think a Q128 rear and Q100H would make a great combo.
You might consider that as in the long run, I don't think a single midi pulling a trailer up hills in Seattle is going to cut it

But overall, I got a lot more ideas from Dave than he got from me. He has a brilliant way of getting to the heart of a problem. He also has a way of rubbing folks the wrong way. I think this is the third time he has been banned @ pedelacs LOL
But alas, as you pointed out, people don't really care much about these hubbies these days
Motomech '11 Motobecane Fathom team, Q100H 201 frt. mounted, 14S Multistar LiPoly, elifebike 9-FET 20A controller. Mean Well HLG-320H-54A, Crazy Bobs on Alex DM32's 21 to 22 MPH.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 24 2018 1:16am

motomech wrote:
Nov 23 2018 11:44pm
You can save yourself a lot of time and just do a proper search here. Just search the posts of either myself, D8veh or chas58 using the keyword Q128. Literally hundreds of posts like;
https://endless-sphere.com/forums/viewt ... h#p1235123
https://endless-sphere.com/forums/viewt ... h#p1088658
https://endless-sphere.com/forums/viewt ... 28#p614826
https://endless-sphere.com/forums/viewt ... 28#p837074
And that's only a sm. sample.
If all info is out there (friendly challenge) what is the gear reduction of the current Aikema 48V Q128H?

Here is another: Motor characteristic curves for non-H 128 motor?

I have read the threads. Some info contradicts, some is outdated, some is good. This thread can make it easier for others, give some solid info based on measurements, and I have intersting stuff not yet on the forums, such as:

9-MOSFET KT sine controller integrated into Hailong battery mount (similar to 6-MOSFET case-08 controller from BMS battery, but stronger)

Aikema parts. As you note before Aikema parts have been unavailable. Apparently no longer true:
AKM Parts.png
Cheers

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Servicing & Gear Reduction (48V 201rpm Q128H)

Post by tomtom50 » Nov 25 2018 4:45pm

Nice CAD view
CAD View.png
The CAD view is current, everthing I saw inside matches.
1. To open unscrew the cover (freewheel side) from the hub body and lift out. I held the cover in a vise with aluminum jaw plates and turned the hub with a strap wrench. The hub cover with the free wheel threads is removed by removing the nut and spacers on the axle.
IMG_20181120_135320.jpg
IMG_20181120_135135.jpg
(I unnnecessarily removed the three screws )
If you do remove the three screws you can lift off the ring gear and see the one-way clutch
IMG_20181120_135050.jpg
2. Remove the three screws attaching the axle stub to the planet gear carrier and pop off the axle stub.
IMG_20181120_134112.jpg
I took off the pinion shaft thrust bearing to get a picture of sun and planet teeth
IMG_20181120_134435.jpg
IMG_20181120_134435.jpg (77.36 KiB) Viewed 4651 times
IMG_20181120_134724.jpg
IMG_20181120_134724.jpg (85.46 KiB) Viewed 4650 times
Ring Gear.jpg
Ring Gear.jpg (113.15 KiB) Viewed 4651 times
IMG_20181120_134243.jpg
IMG_20181120_134243.jpg (89.31 KiB) Viewed 4651 times
Primary reduction
Motor sun gear: 12
Primary planet gears: 44
Primary reduction 3.667

Secondary Reduction
secondary planet gears: 33
Ring gear: 96
Secondary reduction: 2.909

Overall reduction 10.667:1
Motor rpm at 201 wheel rpm: 2144rpm

Finish quality, tolerances, and fit are very good

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Re: Q128H Light & Torquey 800W Hub Motor

Post by Hwy89 » Nov 25 2018 10:13pm

I have a Surly Big Dummy cargo bike with Q128h 201 rpm motors front and rear. They are 48 volt motors run at 52 volts.
It aint fast, tops out at ~19 mph but it can really climb hills. With both motors pulling it rarely gets below 13 mph on the steepest hills and pulls a fully loaded gross weight of 360 pounds.
I rode it from Toledo Ohio to Nashville Tn. With all my camping gear, water and food and never once over heated or had to get off and push. The front wheel doesn’t spin out when the rear is engaged. They seem to be perfectly matched and work together. If I goose it in sand or loose gravel the front will spin especially if I’m trying to turn.
I’m happy with the way it is set up but I have bought two 36 volt 201 rpm motors that I plan on putting on it. If I can keep the climbing ability and increase the speed it will be even better.
Thanks for the link to another source for these motors. I’ve been looking for one for a year or more.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 25 2018 10:27pm

Neptronix mentioned the Bafang G210 as another hub motor with similar power and weight. Unfortunately it is only available with windings too fast for climbing an 8% grade with a 700C wheel. (300rpm 36V / 400rpm 48V).

They are really similar in construction and size
G310Opened.jpg
Q128C-135 & G310.png
Same double-stage reduction ratio. Inrunner motor. And about the same size.
I figure with similar construction and size the Q128H will shed about the same heat (heat = electrical power in - shaft power out), and ebikes.ca has a thermal model of the G310 in their simulator. It turns out the G310 will shed about 132W of heat indefinitely, and if you add ATF that rises to 192W.
G310 Heat Rejection.png
So what does that mean about the 1 mile 8% climb on my commute?
Q128H Hill Climbing.png
The torque lines cross at 14.5 mph, 200W heat being generated in the hub. If heat transfer is similar to the G310 I will overheat in 12 minutes. At 14.5 mph 1 mile is 4.25 minutes, so it should be fine.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 25 2018 10:33pm

Hwy89 wrote:
Nov 25 2018 10:13pm
I have a Surly Big Dummy cargo bike with Q128h 201 rpm motors front and rear. They are 48 volt motors run at 52 volts.
It aint fast, tops out at ~19 mph but it can really climb hills. With both motors pulling it rarely gets below 13 mph on the steepest hills and pulls a fully loaded gross weight of 360 pounds.
I rode it from Toledo Ohio to Nashville Tn. With all my camping gear, water and food and never once over heated or had to get off and push. The front wheel doesn’t spin out when the rear is engaged. They seem to be perfectly matched and work together. If I goose it in sand or loose gravel the front will spin especially if I’m trying to turn.
I’m happy with the way it is set up but I have bought two 36 volt 201 rpm motors that I plan on putting on it. If I can keep the climbing ability and increase the speed it will be even better.
Thanks for the link to another source for these motors. I’ve been looking for one for a year or more.
That totally matches what I'm seeing from the motor data. Not fast but a lot of torque for hill climbing. What controllers are you using? I'm worried mine will have issues with 52V (I have a 52V battery).

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Re: Q128H Light & Torquey 800W Hub Motor

Post by neptronix » Nov 25 2018 11:21pm

Good data right there.

If you think about it, the G310 puts out roughly the same power than the Q128H, and is perhaps a hair larger, but it can only expend 132w continuously, and the Q128H is putting out >150W of heat at it's rated 800W.

But this hill requires 1100-1200w to maintain any decent speed on, ie 15mph. And that's with 100w of pedaling.

Man, a rear chain drive with a 1:1.25 ratio would kick ass with this Q128H, or maybe making a mid drive out of it, or with the bafang because it spins faster.
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Re: Q128H Light & Torquey 800W Hub Motor

Post by Hwy89 » Nov 26 2018 8:48am

“What controllers are you using? I'm worried mine will have issues with 52V (I have a 52V battery).”
I am using S12S sine wave controllers from BMSbattery.com with LCD5 displays. You are correct in thinking that they don’t like the 52 volt battery but it isn’t too much of a problem for me. If I fully charge the pack to 58.8v my controllers will randomly shut off a few times until the pack voltage drops below 56 volts. All I have to do is release the throttle momentarily then reapply and the power is back. Even if it happens on a hill the power is back on before too much momentum is lost. I think there is a 72 volt sine wave controller available but have not tried it.

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 26 2018 2:57pm

Hwy89 wrote:
Nov 26 2018 8:48am
I think there is a 72 volt sine wave controller available but have not tried it.
Thanks, that doesn't sound too bad. I read somewhere that the 72V KT controller is set up for 'normal' 24/36/48/60/72 voltages, and that if you connect a 52V pack it decides between 48V and 60V and sets voltage limits that aren't right for 52V 14S. So you might be best off with what you have.

It would be nice if the manufacturer had a manual that covers stuff like that.

If I had known 52V was not widely compatible I'd have bought a 48V battery. $400 is spent, so I think I'll put up with what you describe.

Your bike sounds pretty cool, have you put a lot of miles on it?

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Re: Q128H Light & Torquey 800W Hub Motor

Post by tomtom50 » Nov 26 2018 3:10pm

neptronix wrote:
Nov 25 2018 11:21pm
Good data right there.

If you think about it, the G310 puts out roughly the same power than the Q128H, and is perhaps a hair larger, but it can only expend 132w continuously, and the Q128H is putting out >150W of heat at it's rated 800W.

But this hill requires 1100-1200w to maintain any decent speed on, ie 15mph. And that's with 100w of pedaling.

Man, a rear chain drive with a 1:1.25 ratio would kick ass with this Q128H, or maybe making a mid drive out of it, or with the bafang because it spins faster.
On the 8% hill and a weight of 110kg 36N-m should do it at 14.5mph, and that is not including any pedal power. The Q128H motor chart
8% climb.png
says 680W shaft power out and 880W electrical power in, 200W heating the hub. It will be interesting to see how closely reality comes to the predictions.

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Re: Q128H & Q100H are Aikema motors

Post by NiToNi » Aug 03 2020 1:32pm

tomtom50 wrote:
Nov 23 2018 1:31pm
I bought a Q100H from BMS Battery about a month ago. It has a BMSBattery label, it looked to me like the BMS label was applied over another label, so I peeled back the Aikema label and;

Q100H Aikema Label.jpg
"AKM-13.0"

Does this mean that the Q100H is exactly the same motor as the Akima 85SXC?

https://wooshbikes.co.uk/?hubkits#85sx

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Re: Q128H Light & Torquey 800W Hub Motor

Post by knutselmaaster » Aug 03 2020 2:38pm

No that is the q85

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Re: Q128H Light & Torquey 800W Hub Motor

Post by NiToNi » Aug 03 2020 3:22pm

OK thanks.

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