Q128C sources?

09Klr650

10 mW
Joined
Feb 25, 2018
Messages
23
Location
Ohio
After some constructive comments on my planned build by motomech I am looking at using a built-wheel Q128C (hopefully as part of a conversion kit). Is BMS Battery the only source for such motors? First the wheels are not offered in a conversion kit. Second I am not thrilled on what I have been reading about their lack of communication when things happen. Is it perhaps offered by another name elsewhere? My searches have yielded little. Basically looking into lower-cost geared cassette wheels. Although I am still thinking of perhaps going front-hub. Decisions, decisions. Thank you.
 
BM Battery isn't that bad. I have been ordering stuff from them for years w/out any problems. When there is a problem, it's usually w/ batteries. I actually had what I thought was a battery failure and they offered me a free replacement if I ordered another motor and payed for the combined freight. But It turned out to be just the on/off switch, which I replaced. It would be extremely rare to receive a bad motor, so the thing to do is to double confirm what you are getting what you want before it's shipped.
You are correct that the Q128C is not currently available built in a wheel. But, you can order the spokes from them, which can save a lot of head ache as getting the right lenght can be tricky w/ ebike hub motor/wheels. Frankly, they are not great spokes, they are not stainless steel and if you live in a humid clime they can surface rust. But they are cheap and I guess a guy could clean they ocassionaly w/ steel wool and even wax them. Ordering the motor min us the build can save on freight and the local bike shop can lace a nice Alex rim(avail. locally)to the motor if that's something you don't want to tackle.
One of the really nice things about the Q128 is that the "C" version can be had in a mid-speed, which is the best speed for the vast majority of builds. One does that by ordering the 328 version that is rated @48V. The 328 designation is for a high-speed motor, but if it was rated @ 36 Volts, it's a 260 (mid-speed) motor.
One of the cons to the Q128 is it's width, which can sometimes interfere w/ a rear disc. brake. But as I recall, your bike has V-brakes and you might leave the rear as it is and add a disc set-up to the frt. If you do that, you can solve the ebrake activation by buying BMS Battery's ebrake lever(s) and using one on the rear
Speaking of sm. stuff, when ordering from BMS Battery, it's a good idea to stock up on some other things which are really cheap. Their spoke wrench and 2 pairs of torque arms are must haves and. I would strongly recommend their Left-hand, half-twist throttle.
Since you will be using 12S LiPoly, I would recommend you pass on any of the BMS Battery sine wave controllers and use a square wave w/ a fixed 42V LVC. I can recommend some if you decide to go this route.
 
motomech said:
You are correct that the Q128C is not currently available built in a wheel.

Speaking of sm. stuff, when ordering from BMS Battery, it's a good idea to stock up on some other things which are really cheap. Their spoke wrench and 2 pairs of torque arms are must haves and. I would strongly recommend their Left-hand, half-twist throttle.
Since you will be using 12S LiPoly, I would recommend you pass on any of the BMS Battery sine wave controllers and use a square wave w/ a fixed 42V LVC. I can recommend some if you decide to go this route.

Thank you for the recommendations. I am assuming the square-wave is the more generic SLA scooter/motorcycle/ebike type?

The Q128C rear is now available built-up in two speeds. https://bmsbattery.com/ebike-kit/769-q128c-135mm-500w-rear-driving-ebike-hub-motor-wheel-ebike-kit.html

I was mainly bemoaning that they do not have a kit, which means figuring out what I want for every piece :). I am still considering front-drive for compatibility across all the two-wheeled vehicles I plan on. Or as I said before, eventually buying both. Hm . . . I guess I could buy the front-drive Q128 kit AND the separate rear Q128C wheel at the same time! I plan on putting the controller oin the battery bag anyway with quick-connects and it is not like I need to buy a lot of additional items for the kickbike. LCD, throttle alone would handle it as no PAS is required.

I will take a look at the controllers you mentioned. However I think it would be best to stick with right-hand throttle as that more closely matches the motorcycles I am familiar with. Muscle memory can be a major pain in panic situations!

Thank you again!

Edit to add: Anyone know the differences between the Bafang BPM2 500W front drive and the Q128 400-500W front drive set-up?
 
Alan B said:
Shipping costs are high so combining things and making a larger order can be a good plan. Get some spare parts to have on hand as well. Having a spare motor, gears, etc might be worthwhile as well if you don't want to incur additional delays and costs later.

Ah, gears. Good point. They are plastic from what I have seen. The good news is if I decide to buy a Q128 front for the kickbike and a Q128C for the Schwinn the replacement parts will be common. I assume you mean by buying an entire motor I can switch out the gears and stator as a unit if needed? Makes sense.

I suppose a second controller, spare throttle and PAS sensor would be a cheap insurance policy.

Thank you.
 
I was mainly bemoaning that they do not have a kit, which means figuring out what I want for every piece :).
You are making a battery harness w/ 10 Ga. wire and XT60 connectors and you are worried about connecting a few components?
Most kits require some finiggling. Actualy, what BMS Battery calls a "kit" is just the motor and wheel
Tell you what, something just came to mind, search for the MXUS "waterproof" front mini geared kit. The entire thing uses multi-pin push/pull connectors and the motor is sm. enough to be frt. mounted since you seem to be stuck on this idea..
A couple builds have been doc'ed here, one recently was purchased on Aliexpress and the other, a year or two back was obtained from the MXUS factory.
I plan on putting the controller oin the battery bag anyway with quick-connects and it is not like I need to buy a lot of additional items for the kickbike. LCD, throttle alone would handle it as no PAS is required.
I have no idea what you are refering to as "Quick connectors", are you going to include the one or two dozen wires from the controller? The controllers I use(That come w/ the PAS, throttle, display, etc.) are $30 to $40 shipped, why would go to all that trouble for such an inexpensive thing?
Overall, it's a bad idea.
I think it would be best to stick with right-hand throttle as that more closely matches the motorcycles I am familiar with. Muscle memory can be a major pain in panic situations!
Common noobie misconception.
I was a motorcycle tech. for over 30 years and it took me about a minute to get used to a left hand throttle, it's totally intuitive. The reason one goes with the left-hand throttle is the frt. chain ring is not used w/ a motor and the shifter can be removed to free up throttle space. If you put it on the right, you are going to relocate the shifter that does get used. As to how much, well, that's the other major misconception that folks that have never ridden an ebike have. That they will be shifting a lot. The reality is, with a motor of any power of all, only 2 or 3 gears get used.
Good luck.
 
motomech said:
You are making a battery harness w/ 10 Ga. wire and XT60 connectors and you are worried about connecting a few components?
Tell you what, something just came to mind, search for the MXUS "waterproof" front mini geared kit. The entire thing uses multi-pin push/pull connectors and the motor is sm. enough to be frt. mounted since you seem to be stuck on this idea..
A couple builds have been doc'ed here, one recently was purchased on Aliexpress and the other, a year or two back was obtained from the MXUS factory.

Soldering I know. Wiring I know. But the ebike tech? Still a newbie. I will take a look at the MXUS.


motomech said:
I have no idea what you are refering to as "Quick connectors", are you going to include the one or two dozen wires from the controller? The controllers I use(That come w/ the PAS, throttle, display, etc.) are $30 to $40 shipped, why would go to all that trouble for such an inexpensive thing?
Overall, it's a bad idea.

Mainly theft. It is quite hard in my area to keep what is yours, yours. I have had everything from lawn mowers to 20oz bottles of soda stolen (thank you thief for the $400 to replace that car window :( ).

motomech said:
Common noobie misconception.
I was a motorcycle tech. for over 30 years and it took me about a minute to get used to a left hand throttle, it's totally intuitive. The reason one goes with the left-hand throttle is the frt. chain ring is not used w/ a motor and the shifter can be removed to free up throttle space. If you put it on the right, you are going to relocate the shifter that does get used. As to how much, well, that's the other major misconception that folks that have never ridden an ebike have. That they will be shifting a lot. The reality is, with a motor of any power of all, only 2 or 3 gears get used.
Good luck.

Good point. People tend to keep to the middle ring to reduce extreme chain angles anyway. Do they eliminate the shifter entirely, or relocate to a somewhat reachable place "just in case"?
 
09Klr650 said:
Good point. People tend to keep to the middle ring to reduce extreme chain angles anyway. Do they eliminate the shifter entirely, or relocate to a somewhat reachable place "just in case"?

FWIW, I kept my short twist throttle on the right hand side since the one that came with my kit was right-handed. I found I could mount it with the shifters with just a little bit of futzing around, but my throttle does force the trigger shifters inboard a bit and they aren't optimally placed. Nonetheless, shifting to lower gears is easy, but shifting back up requires a bit of a reach (I have normal to small sized hands). But as Motomech sez, you don't shift that much anyway, so no big deal.

On an e-bike you'll probably be on the large chainring most of the time. The middle (or low in my case since I changed to a road chainring set for the larger 53T big ring) chainring would be rarely used. You could ditch the derailer completely and simply get off the bike and move the chain manually for those "just-in-case" emergency situations (another reason to lube the chain with paraffin wax rather than oil.)
 
wturber said:
You could ditch the derailer completely and simply get off the bike and move the chain manually for those "just-in-case" emergency situations (another reason to lube the chain with paraffin wax rather than oil.)

I laughed at that. I am one of the sacrilegious ones who lubes his motorcycle chain . . with WD40 :shock: . A spray and wipe every 100 miles or so.
 
Good point. People tend to keep to the middle ring to reduce extreme chain angles anyway. Do they eliminate the shifter entirely, or relocate to a somewhat reachable place "just in case"?
I remove mine completely. All three of my Mountain bikes came with a 44T large chain ring. In order to be able to pedal along at least 20 MPH, I replace it w/ a 48 T and to pedal even a little faster, a 50T. Normaly, removing the derailleur will allow the chain to "pop-off" at times, but since the 48 or 50 T sprockets pull the chain tighter, it won 't come off. Now, if I was using the highest gear(biggest sprocket on the 9-speed cassette), there might be a problem with the chain getting too tight. But I only use the three smallest gears and it all works out very well.
The alignment thing is only a consideration when one is on the highest(biggest)gears on the cassette.
 
If you buy the BMSbattery battery with integrated controller, it looks like they use the single 9 pin connector to the motor, and a multi-pin cable that ties together the throttle, LCD, and brake levers. Cleans up the wiring a lot, unless it turns out too long for your bike.

For a separate controller, I think PSWpower.com has a better price for the 17A and 20A controller kits (add brake levers, LCD< PAS sensors, etc). They run on 36V/48V/52V and the shipping charges seem to be lower.

I did buy two Q100H and one Q128H in three separate orders from BMSBattery. Last purchase was in December. I bought them as bare motors. By lacing them myself, I could use Saphim strong spokes, 14G with 13G ends, and rims of my choice, instead of generic 13G spokes. Saved some money too., Shipping for a wheel is crazy.




.
 
I love my Q128 H 201 rpm rear motor. Unfortunately in a moment of stupidity I tackled one hill to many and stripped the gears. The hill was steep and rough gravel about a half mile long. It was too rough to keep my speed up so I assume that the motor got hot enough to soften the plastic gears. I made it to the top but my nice quiet motor now sounds like string trimmer in a patch of weeds.
I already had an order in with BMSBattery.com for 3 more motors for other projects so I won't be down for long. I asked Bmsb if they could supply replacement gears and the answer was no. And a few hours of research didn't turn up an alternative source.
So my question is: should I lace one of the new motors into my rim or just open them up and move the new gears to the old motor?
Has anyone else had any luck sourcing parts for the Q128?
 
This seller seems to offer replacement gears for the Q128 series:

https://www.ebay.com/itm/Q128-Q128H-Q128C-800-Watts-hub-motor-gears-three-gears/163037182978
 
Hwy89 said:
I love my Q128 H 201 rpm rear motor. Unfortunately in a moment of stupidity I tackled one hill to many and stripped the gears. The hill was steep and rough gravel about a half mile long. It was too rough to keep my speed up so I assume that the motor got hot enough to soften the plastic gears. I made it to the top but my nice quiet motor now sounds like string trimmer in a patch of weeds.
I already had an order in with BMSBattery.com for 3 more motors for other projects so I won't be down for long. I asked Bmsb if they could supply replacement gears and the answer was no. And a few hours of research didn't turn up an alternative source.
So my question is: should I lace one of the new motors into my rim or just open them up and move the new gears to the old motor?
Has anyone else had any luck sourcing parts for the Q128?

[strike]Can't help with your parts search; but if you are in UK/Europe and want to get shot of your broken Q128H, I will buy it, if the price (and shipping) are reasonable.[/strike]

(And then I noticed "North Arizona" :( )
 
1N4001 said:
This seller seems to offer replacement gears for the Q128 series:

https://www.ebay.com/itm/Q128-Q128H-Q128C-800-Watts-hub-motor-gears-three-gears/163037182978

Thanks 1N4001, that would come to about $55.00 US shipped from London. Cheaper than a new motor from BMSB.
The seller does not specify motor RPM so I have to ask another question. Is a geared motor's RPM determined by the number of windings or by the gear ratio. I have always assumed that the fast and slow models had different gear sets. Mine is the slow 201 RPM model.
 
Hwy89 said:
I love my Q128 H 201 rpm rear motor. Unfortunately in a moment of stupidity I tackled one hill to many and stripped the gears. The hill was steep and rough gravel about a half mile long. It was too rough to keep my speed up so I assume that the motor got hot enough to soften the plastic gears. I made it to the top but my nice quiet motor now sounds like string trimmer in a patch of weeds.
I already had an order in with BMSBattery.com for 3 more motors for other projects so I won't be down for long. I asked Bmsb if they could supply replacement gears and the answer was no. And a few hours of research didn't turn up an alternative source.
So my question is: should I lace one of the new motors into my rim or just open them up and move the new gears to the old motor?
Has anyone else had any luck sourcing parts for the Q128?

Instead of swapping just the gears, you can often unscrew the old core from its laced shell and screw in the core of a new motor. I've done this with the Q128c and it worked fine.
 
Thanks Molybdenum, I will give that a try as soon as I get my order from BMSB. I am also going to order the set of gears from the Ebay seller in London. If they turn out to be the right parts maybe I'll be able to repair the core too and keep it as a spare.
 
You will need to make a core removal tool. This thread has some links to various tools members here have used to unscrew the core: https://endless-sphere.com/forums/viewtopic.php?f=2&t=88303&p=1288267&hilit=q100+cover#p1288267

I used the one similar to that of ntr (bottom of page), but I had to double up on the steel to keep it from bending. Be sure to put the metric screws (M5 i think?) so they-re in the three holes and flush with the tool to prevent it from shifting and damaging the threads.
 
Hwy89 said:
Thanks Molybdenum, I will give that a try as soon as I get my order from BMSB. I am also going to order the set of gears from the Ebay seller in London. If they turn out to be the right parts maybe I'll be able to repair the core too and keep it as a spare.
Are you sure that it's your gears that are stripped and not a hall sensor or mosfet problem that also makes your motor go rough and noisy?

You should disassemble the motor and check the gears before ordering anything.

Also, test the hall sensors and measure the mosfets in the controller. To check the mosfets, disconnect the controller completely and measure the resistance between each phase wire and the red wire that copnnects to the battery. the results should be in the range 7K to 14K, but they should all be the same. Repeat the test using the negative battery wire. Again they should all be the same in the range 7k to 14k.
 
Good advice D8veh, I had actually placed an order for 3 new motors and controllers before this motor crapped out so I decided to postpone tearing it down until I had parts on hand to fix or replace it. Just checked tracking on that order and it arrived in Phoenix this morning so should be delevered tomorrow. I also ordered a set of gears from Ebay being shipped from London England but don't know when to expect delivery. Have house guests all week so I won't be getting much done untill they all clear out.
I will be putting dual Q128s (201 RPM slow wind) on a Surly Big Dummy cargo bike and putting on a 14S 12P pack of Tesla cells.
 
I recieved my shipment of new motors and the next day the set of gears from London England so today I took my motor apart. I wasn't able to remove the three screws that hold the gear retaining plate. I tried using a hand impact screwdriver but all I acomplished was deforming the philips driver tip that came with the impact driver. I stopped before it completely stripped the screw head so there is hope of still being able to remove the screws if I get a better impact driver. Any advice on what type to buy?
From what I can see the gears don't look like they are damaged but it takes a lot of force to rotate them. I opened one of the new motors and the gears can be turned with about 1/4 of the force it takes to turn the old motor. I can see alignment marks on the new motor but not on the old one. If the motor slipped a little and the gear alignment marks didn't match up would it result in the gears not meshing correctly and being hard to turn?
 
usually the supplied tips are pretty hard. You could try another bit, but you might need an adaptor, 1/4" to 3/8th, or even two, 3/8th to 1/2. There is a bit of technique involved. Lot's of pre-load w/ the hand gripping the driver and a big hammer. At this point, if the PHillips doesn't loosen them, you might think about cutting a slot W/ a Dremel tool and using the slotted bit. It will leave some marks in the cover, but they will be covered by the cassette/free whl.
I don't think the gears can move a tooth w/out totally wiping them out. They probably have gotten hot enough to partially melt and deform.
 
I finally got my motor apart after getting a set of hardened tips for my impact driver. Not sure about the others but the phillips tip that came with the driver was definitely mild steel.
The gears look absolutely perfect. With the plastic gears removed the metal sun gear still would barely turn so I split the motor halves to look inside. I inspected all of the rotor poles and magnet surfaces for rub marks or any sign of dragging and found none. I tried lifting each magnet and none of them were loose. I spun the bearings and both seemed free and well lubed. So I put the halves back together. The rotor will turn by hand but not easily. I shorted the phase wires 2-2-2 and each combo locked the rotor so it could not be turned at all .
At this point I slipped the core from one of my new motors into the housing laced to my rim and reinstalled it on my bike. Easy peasy and I'm back to having a smooth quiet ride.
I would really like to know what happened to that motor but they are on sale at $79 plus shipping so I will always keep a spare.
Thanks all for the advice.
 
BMSBattery Q109H is an Aikema motor (just got one, Aikema later under BMS label)

Aikema motor serials start AKM.

Topbikekit sells Aikema AKM100H, same motor. I asked for quote on AKM128H, they can sell, price $109. So they sell Aikema 128 motors.

I have not figured out shipping, not sure how total cost compares.

I hope topbikekit is a good vendor, they sell interesting stuff. For example KT sinewave 22A 9 mosfet integrated controller for Hailong case. BMS integrated controller is 6 MOSFET.
 
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