800W Q128c commuter build

molybdenum

1 kW
Joined
Feb 20, 2014
Messages
301
Location
Burnaby, BC, Canada
Thanks to the ES community, I had some excellent build advice for my first build, which was a 2.3kV capable clyte based hardtail with homemade 17s 15Ah LiMn battery. Once again, I return seeking advice on a new project. I have read many threads on related topics to gather information that may help with this new build.

My situation has changed since my first build and for the past year, I have needed to drive my kids to school and my current e-bike is too heavy for my hitch mounted bike rack. Most days, I was taking a non-electric hybrid on the car and riding the 14 km to work after dropping off the kids and returning for the car at the end of the day. This worked fine for a while, but I suffered neck injuries last October after being hit by a car while riding my bike to work and my recovery has been slow. I'm finally at the point where I can take my bike on a car rack and ride the remaining 3-4 km to work, then return to the car for the trip home; but some days I am too sore to ride at all.

Other than a sore neck, I'm a fairly fit rider and would like to stay that way if possible, so I'm considering 500-800W output with scalable pedal assist would give me the option of extra help on those not-so-good days. It needs to be light enough and balanced about the top tube to fit on the bike rack. I will need easily removable batteries because I can no longer get my e-bike near a power source to recharge. I like the idea of a geared hub, which spins freely and can be ridden like a normal bicycle without resistance.

I'm considering converting my 2012 Kona Dew Deluxe (56 cm aluminum frame, no suspension, 700c wheels) and installing a rear 500+W geared hubmotor. To be safe, I will need about 45-50 km range with pedalling. I plan to build my own 48V battery from high discharge cells. Most of my 28 km 2-way commute consists of fairly light grades, with a few 100 m+ 4-5% grades and two 40-60 m 8% grades. Charging non-lipo batteries at work would be an option, which I might take to keep the weight down.

To mount the bike on a car carrier, I will need to distribute the weight between the front and back. I’d like it to be discrete, so I'm considering a low profile rear hub counterbalanced with a grocery bag battery in a basket mounted to the handlebars. I'm strongly considering the Q series of rear geared motors from BMSbattery for their small size, but I have some questions, as their site doesn't offer much in the way of information and I’d like to get the right stuff (I hear this can be a problem even if you know exactly what you need :shock: ).

Q128H-135mm 800W Rear Driving EBike Hub Motor
-Their website says it’s 201RPM unloaded and 36V; would this spin closer to 250RPM at 48V? What top speed would it give at 48V? My back of the napkin calculation suggests 33 kph unloaded for the q128h at 48v, which seems slow, and ideally, I’d like to have assist up to 32kph at least.

-S12SH 800W 35A Sine Wave Controller
- The controllers recommended for the Q128H are only 500W; will this one work with the Q128H?

-S-LCD3 LCD Meter for S-Series Controllers
- I’m guessing I need one of these for the PAS if I go with the S12SH, which comes with a "simulated torque" feature. Is this feature usable for a mainly PAS build, or would I be better off using a different controller and a V3 cycle analyst??
 
I’ve bought 2qty Q128H (screw cover) and a couple Q100CST’s and I’m still thoroughly confused with BMS Battery motor rpm specs. I wouldn’t assume Q128H 201 rpm is based on 36V. I say it’s based on 48V system.

My 201 rpm Q128H’s topped out about 35-38km/h in 700c wheels but ‘had to use 60-67V (16S RC Lipo) to achieve that speed.

Check my sig pg 2-3 for a couple pics and some road data. Climbs great on rated 800W power but it’s spinning pretty fast on 16S RC Lipo.
 
To mount the bike on a car carrier, I will need to distribute the weight between the front and back. I’d like it to be discrete, so I'm considering a low profile rear hub counterbalanced with a grocery bag battery in a basket mounted to the handlebars.

It's unclear to me how a basket on the frt. is going to counter-balance a rear motor and rear rack mounted batteries. If you don't get the battery pack in the the triangle, you are not likely to achive anything close to frt. to rear balance.

Q128H-135mm 800W Rear Driving EBike Hub Motor
-Their website says it’s 201RPM unloaded and 36V; would this spin closer to 250RPM at 48V? What top speed would it give at 48V? My back of the napkin calculation suggests 33 kph unloaded for the q128h at 48v, which seems slow, and ideally, I’d like to have assist up to 32kph at least.

'201" on 48 V is actually closer to 260 rpm. Top speed in 700 wheel would be 21 to 22 mph(32 to 35 Kph).
You might want to consider the 48V "328" motor. It equates to something like a Mac code 8.
Top speed looks to be about 38 to 41 Kph and it would still be able to handle your fairly short hills.
Either motor would work.

-S12SH 800W 35A Sine Wave Controller
- The controllers recommended for the Q128H are only 500W; will this one work with the Q128H?

Let me preface that question. I.M.O., it would be a mistake to toss your 9-speed cassette for a clunky DNP free wheel the QQ128H motor would require. Stay with the 128C and use the 25 A sine wave S12S. 900 Watts is plenty for that donor bike.

-S-LCD3 LCD Meter for S-Series Controllers- I’m guessing I need one of these for the PAS if I go with the S12SH, which comes with a "simulated torque" feature. Is this feature usable for a mainly PAS build, or would I be better off using a different controller and a V3 cycle analyst??
These controller require one of the compatable displays and the SLCD-3 would be a good choice. The 5-range current limiting divides the increments in smaller pie slices(more versitility)and the current limiting reduces the tendency of the motor to lunge when the PAS is engaged.

I see two areas that I see which may require special attention for this combo and both have to do with the motor fitment.
First, the Kona's dropouts look very spindly an with the Q128's torque, good Torque arms on both sides would be advisable.
Second, The Q128 form factor is such that, while the diameter is reduced, the width is increased. It is possible the motor side cover will contact the rear brk. caliper and require a bigger disc and caliper adapter. Perhaps ykick can comment on this.
 
Ykick said:
I’ve bought 2qty Q128H (screw cover) and a couple Q100CST’s and I’m still thoroughly confused with BMS Battery motor rpm specs. I wouldn’t assume Q128H 201 rpm is based on 36V. I say it’s based on 48V system.

My 201 rpm Q128H’s topped out about 35-38km/h in 700c wheels but ‘had to use 60-67V (16S RC Lipo) to achieve that speed.

Check my sig pg 2-3 for a couple pics and some road data. Climbs great on rated 800W power but it’s spinning pretty fast on 16S RC Lipo.

Very nice build; I read your thread carefully and would consider higher voltage/lower amps as a means of getting a desirable topspeed, and I'm quite flexible about which voltage battery I assemble.

I see your latter settings used 16S RC Lipo (66V off charger, 5Ah). Lyen 6 FET Controller with 13-14A battery current and 30A phase current. This would put just over 800W through the motor and the higher voltage results in 35-38km/h - perfect if I can get my hands on a 6fet Lyen controller.

I can also see from your consumption data, a 16km ride would burn about 3.5Ah
A similar battery would be 16s4p = 64 x 1.5Ah 18650s At 45g/cell x 64 cells = 2.9kg or just over 6 pounds - manageable, but I might have to charge at work if I can't keep consumption down. Wish I could use Lipo!


Ykick said:
Just a quick public service announcement - OFG's riding 26" DD eBikes owe it to themselves to try a lightweight 700c eRoadie. It's hard to believe there's major differences from our usual 26" DD eBikes but it's night/day.

Hell, merely riding in rain with narrow 700c tires throws much less water up in the air than the fat 26" tires I'm accustomed to using. Caught in a shower on wet roads without fenders and didn't suffer nearly as much mess.

Plus, 40lb ebike with freewheeling makes meaningful pedaling much more satisfying while the incredible efficiency and range capabilities from small battery pack opens up a whole new world of possibilities. And actually starting to get genuine exercise!

I think this is what gets me excited.


motomech said:
'201" on 48 V is actually closer to 260 rpm. Top speed in 700 wheel would be 21 to 22 mph(32 to 35 Kph).
You might want to consider the 48V "328" motor. It equates to something like a Mac code 8.
Top speed looks to be about 38 to 41 Kph and it would still be able to handle your fairly short hills.
Either motor would work.

32-35 kph should be plenty of assist for that bike and 260RPM would be a good compromise from the 328, which may be too fast for longer hills imo.

I'm guessing that the Q128c 500W, 36V 201RPM option from BMSbattery would spin at 260RPM, given 48V?


motomech said:
Let me preface that question. I.M.O., it would be a mistake to toss your 9-speed cassette for a clunky DNP free wheel the QQ128H motor would require. Stay with the 128C and use the 25 A sine wave S12S. 900 Watts is plenty for that donor bike.

I'd really like to keep the cassette if possible, but I was considering that the Q128H might be more tolerant of abuse (high volts/amps. Also, do you think a Q128C with 9spd cassette would fit in 135mm dropouts?

I've also heard the space required for mounting the Q128C is 141mm irrespective of cassette size. Going to a smaller cassette and adjusting out the top gear(s) would also be an option. If I order the Q128c, for what it costs, I may as well also get the 25 A sine wave S12S controller and SLCD-3 to try out.


motomech said:
These controller require one of the compatable displays and the SLCD-3 would be a good choice. The 5-range current limiting divides the increments in smaller pie slices(more versitility)and the current limiting reduces the tendency of the motor to lunge when the PAS is engaged.

I see two areas that I see which may require special attention for this combo and both have to do with the motor fitment.
First, the Kona's dropouts look very spindly an with the Q128's torque, good Torque arms on both sides would be advisable.
Second, The Q128 form factor is such that, while the diameter is reduced, the width is increased. It is possible the motor side cover will contact the rear brk. caliper and require a bigger disc and caliper adapter. Perhaps ykick can comment on this.

Looking at my clunky hydraulic disc brakes, I think you're right. I think I have a 203 rotor and adapter lying around somewhere. The dropouts look very fragile indeed. I'm nervous about trying to stretch them too much for that reason - maybe 5mm is OK but not a whole lot more. Good quality torque arms are definitely on order.

Thanks very much for the replies and good advice. I'm starting to gain some perspective.
 
I'm guessing that the Q128c 500W, 36V 201RPM option from BMSbattery would spin at 260RPM, given 48V?
Yes.
I'd really like to keep the cassette if possible, but I was considering that the Q128H might be more tolerant of abuse (high volts/amps.

My experience w/ Q100's is, they are not that prone to overheating as long as the climb speed is kept above 1/2 of the no-load speed. I ran a sim. on the Ebike CA sim using the MXUS FXO7 201 motor(sized between the Q100 and the Q128) on 48V/25A and the time to overheat was 20 min. I think you will be up and over long before overheat.

Also, do you think a Q128C with 9spd cassette would fit in 135mm dropouts?

I've also heard the space required for mounting the Q128C is 141mm irrespective of cassette size. Going to a smaller cassette and adjusting out the top gear(s) would also be an option.
Your 9-speed will fit. During the recent design, the Q128 became a true 135 mm drop-out motor. Even if you end up at 141 mm, spreading those chain stays will be very easy, probably can do it by hand. Spreading the chain stays that amount does not put any undue stress on the drop-outs.

The dropouts look very fragile indeed. I'm nervous about trying to stretch them too much for that reason - maybe 5mm is OK but not a whole lot more. Good quality torque arms are definitely on order.
[/quote]

You won't need Dr Bass's TA's :D
I think just a pair from BMS Battery will do if a pair is used. That's all I used with a Ezee geared on 900 Watts in my Rocky mountain. Here is the same set-up on a 100C;

100_0039.JPG

100_0040.JPG

The slotted pieces I got off Ebay, but you can make something if if you have basic tools.

I would order 2 pairs, they are good to have the parts, even if you end up combining them w/ something like a custom Grin TA.
People diss them, but they are hard as diamonds.
Actually, I always order bunch of stuff when ordering from BMS B. They little stuff costs almost nothing when shipped with a motor/Rim.
You will need a PAS, but do not order the new Dual Hall one, it's not working right.

Also, I you don't have one for 13 Ga., a spoke wrench.
I'm a big fan of left-hand, half-twist throttles and BMS B. is one of the few places that sell them.

Lastly, with these BIG Three vendors in China, commucation is the key, talk to them though out the entire process to prevent mix-ups.
 
I don’t think you need 2 torque arms. Derailleur hangar is usually steel and/or some hardened alloy so that gives me plenty of confidence on the drive side.

I do use TA (torque arm) on the brake side. And remember, TA’s aren’t meant to regularly hold the axle from spinning. Properly tightened axle nuts should do that. TA’s are merely a last line of defense/protection in the event you mess-up installing axle hardware at some point. And since gear motors can't regen there's really no mechanism for the axle hardware to loosen on it's own.

These newer motors are likely different gearing from my older Q128H with screw cover. But, 201 rpm motors I used needed 60-67V to reach 20-24MPH level flat, no wind, no pedal input with 700c wheel. That’s all I’m gonna say about the RPM specs.

I don’t use disc brakes on these motors so I can’t comment about potential caliper or rotor interference?

Spreading dropouts can be done gently prying with a screwdriver against the motor housing while slipping the axle into the dropouts. 5mm or so isn’t bad IMO and I do it all the time on the aluminum frame.

Gotta play with washers, nuts and axle hardware a little get the best dropout fit and then perhaps some wheel truing/dishing to line everything in the dropouts the best it can be.
 
This is great information and I think it's all coming together; I'll be ready to order some parts very soon.

I will likely order the unlaced q128c motor and lace it into an Alex DM18 to match the front wheel, which was rebuilt following the collision.

Here's the parts list so far:

Q128C-135mm 500W 201RPM@36V $112.00 US
S12S 500W Torque Simulation Sine Wave Controller $34.00 US
S-LCD3 LCD Meter for S-Series Controllers $29.90
PAS--Pulse Padel Assistant Sensor With 12 PCS Magnets $4.65 US
Ebike torque arms $15.00 US
$194 USD total, which equates to $250 duckbucks at today's exchance rate.

I have enough Doctorbass Konion lying around for either a 13s4p, or even a 16s4p battery build. I'll have to order a compatible charger.


motomech said:
My experience w/ Q100's is, they are not that prone to overheating as long as the climb speed is kept above 1/2 of the no-load speed. I ran a sim. on the Ebike CA sim using the MXUS FXO7 201 motor(sized between the Q100 and the Q128) on 48V/25A and the time to overheat was 20 min. I think you will be up and over long before overheat.

So I guess the trick is to keep it above ~15kph on hills. Lacking experience with Q128's, I'll have to try it out and see what happens. Has anyone installed a thermistor in these motors?


motomech said:
Your 9-speed will fit. During the recent design, the Q128 became a true 135 mm drop-out motor. Even if you end up at 141 mm, spreading those chain stays will be very easy, probably can do it by hand. Spreading the chain stays that amount does not put any undue stress on the drop-outs.

This is very good news, and I'm very much looking forward to riding a bike-like ebike, and thanks for the images of your torque arm setup. I can also see yor rear disc rotor nicely clears your Q100 and your calipers sit just above. What size rotor are you using there? I'm thinking 203s would be absurd overkill :D


motomech said:
Lastly, with these BIG Three vendors in China, commucation is the key, talk to them though out the entire process to prevent mix-ups.
Mixups can happen with any vendor, and I will take your sagely advice and communicate in simple terms throughout.


Ykick said:
I don’t think you need 2 torque arms. Derailleur hangar is usually steel and/or some hardened alloy so that gives me plenty of confidence on the drive side.

I do use TA (torque arm) on the brake side. And remember, TA’s aren’t meant to regularly hold the axle from spinning. Properly tightened axle nuts should do that. TA’s are merely a last line of defense/protection in the event you mess-up installing axle hardware at some point. And since gear motors can't regen there's really no mechanism for the axle hardware to loosen on it's own.

I can see what you mean about the derailleur hangar and the regen, which would reliably loosen my nuts to the point where I had to install nordlocs on my other build.


Ykick said:
These newer motors are likely different gearing from my older Q128H with screw cover. But, 201 rpm motors I used needed 60-67V to reach 20-24MPH level flat, no wind, no pedal input with 700c wheel. That’s all I’m gonna say about the RPM specs.

My 36V 201 RPM Q128 should spin at 260RPM at 48V

A 700c wheel is about 0.7 m diameter with tire: (0.7 m x pi x 260RPM/min x 60min/hour = 34.3 kph unloaded speed. This might yield 24 kph (70%) under load. Under the same formula and assuming a linear relation between volt increases, 66V/48V x 34.3 kph = 47.2 kph unloaded and 33kph under load. Interestingly, when I plug in a 48v 250RPM motor into the ebikes.ca motor simulator, I get a 34kph top speed estimate; maybe I'm missing something?

24 kph is too slow for me, and I will be looking into higher voltage controllers. To start, I'll use the BMSB 48v S12S controller since it's cheap enough and it'll get me in the game quickly. Maybe this will be sufficient considering it is to be a light pedal assist type build. I'll plan to build the battery in a manner that allows easy expansion to 16s in case I want to upgrade.
 
I can also see yor rear disc rotor nicely clears your Q100 and your calipers sit just above. What size rotor are you using there? I'm thinking 203s would be absurd overkil
The standard disc. I think it's a 160 mm. this is my bike;

http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?year=2003&brand=Rocky+Mountain&model=Edge
Cutes are so sm., they don't even come close to the caliper.
But my old MXUS geared made contact, but I was able to file the caliper to clear.
The MXUS geared mini has about the same dimension as the Q128.
Here is a diagram of an Outrider, which is the same housing as the MXUS;
http://www.aliexpress.com/store/product/Outrider-Hot-sale-good-quality-e-bike-36V-300W-rear-gear-motor-for-electric-bike-EN15194/710912_32475177005.html
I guess that is why the MXUS mini wheels are always laced w/ all spokes as "inners";
https://endless-sphere.com/forums/viewtopic.php?f=3&t=74164
Here is a standard QQ128;
http://www.elifebike.com/upfile/dtpic/2011/1G/KSU5.3DNYT/1GKXM7_6WT84.jpg
I'm pretty sure you will have to move the caliper, will be interesting to see.
My 36V 201 RPM Q128 should spin at 260RPM at 48V

A 700c wheel is about 0.7 m diameter with tire: (0.7 m x pi x 260RPM/min x 60min/hour = 34.3 kph unloaded speed. This might yield 24 kph (70%) under load. Under the same formula and assuming a linear relation between volt increases, 66V/48V x 34.3 kph = 47.2 kph unloaded and 33kph under load. Interestingly, when I plug in a 48v 250RPM motor into the ebikes.ca motor simulator, I get a 34kph top speed estimate; maybe I'm missing something?

Yes, that is what I said;
"201" on 48 V is actually closer to 260 rpm. Top speed in 700 wheel would be 21 to 22 mph(32 to 35 Kph).".

24 kph is too slow for me, and I will be looking into higher voltage controllers. To start, I'll use the BMSB 48v S12S controller since it's cheap enough and it'll get me in the game quickly. Maybe this will be sufficient considering it is to be a light pedal assist type build. I'll plan to build the battery in a manner that allows easy expansion to 16s in case I want to upgrade.
So where do you get the 24 Kph?
If 34 Kph is too slow for you, order the 48V Q128 328, which I don't think you understood what this is when I mentioned it before. It's the same as Q128 36V 260! That this motor speed is available is one of the great things about the Q128. It's N.A. in the CST Cutes :cry:
My experience w/ Q100's is, there is little performance difference between the 201 and the 260. the 260 is faster and only at the lowest couple mph does the 201 pull harder. In real World riding, the difference between the 260 and the 328 feels much greater.
Most of the rider reviews I've seen of the Q128 were over at Pedelecs UK, in particular, Dave'ws(D8veh). He said the torque of the Q128 was closer to the BPM, than the Q100 and while he was testing the H, I think you will fine the CST to be torquy as well.
If your goal with this bike is nice pedal assist, you don't want to change the controller. The Sine waves are about as good as it gets without going all the way up to the high-priced systems. If you go to an INfineon, your system will be noisier and you will lose all the features of the LCD-3.

Use the Outrider standard as a sub for the Q128 48V 328 on the Ebike CA sim. to check performance, but keep in mind the Q128 will climb much better than the Outrider.
 
Here is the thread Dave started concerning the Q128;

http://www.pedelecs.co.uk/forum/threads/q128h.20980/page-4

Here is his very good explanation of the advantages of the 5-range current limiting when used w/higher powered sysytems;

<<<<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.>>>>
 
motomech said:
24 kph is too slow for me, and I will be looking into higher voltage controllers. To start, I'll use the BMSB 48v S12S controller since it's cheap enough and it'll get me in the game quickly. Maybe this will be sufficient considering it is to be a light pedal assist type build. I'll plan to build the battery in a manner that allows easy expansion to 16s in case I want to upgrade.
So where do you get the 24 Kph?
If 34 Kph is too slow for you, order the 48V Q128 328, which I don't think you understood what this is when I mentioned it before. It's the same as Q128 36V 260! That this motor speed is available is one of the great things about the Q128. It's N.A. in the CST Cutes :cry:
My experience w/ Q100's is, there is little performance difference between the 201 and the 260. the 260 is faster and only at the lowest couple mph does the 201 pull harder. In real World riding, the difference between the 260 and the 328 feels much greater.
Most of the rider reviews I've seen of the Q128 were over at Pedelecs UK, in particular, Dave'ws(D8veh). He said the torque of the Q128 was closer to the BPM, than the Q100 and while he was testing the H, I think you will fine the CST to be torquy as well.
If your goal with this bike is nice pedal assist, you don't want to change the controller. The Sine waves are about as good as it gets without going all the way up to the high-priced systems. If you go to an INfineon, your system will be noisier and you will lose all the features of the LCD-3.

I was thinking that 260RPM is the unloaded wheel speed. I completely defer to your real world experience with these Q series motors; 32-34kph should be plenty fast for this donor bike and 260RPM should perform better on hills than 328.


motomech said:
Here is the thread Dave started concerning the Q128;

http://www.pedelecs.co.uk/forum/threads/q128h.20980/page-4

Here is his very good explanation of the advantages of the 5-range current limiting when used w/higher powered sysytems;

<<<<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.>>>>

Thanks for the link; I read some of Dave's other pedelecs.co.uk posts but missed this one, which does describe the 5 stage pedal assist quite nicely. The primary mission is to build a light weight but capable pedal assist commuter ebike. It would also be a shame to give up the sinewave controller, which should power the motor quietly and smooth as butter. Is BMSB's LCD-3 version the only S series controller compatible LCD offering 5 levels of pedal assist?

In hopes of furthering knowledge of these seemingly versatile, often overlooked smaller motors, I'll definitely be posting my own observations regarding caliper clearance and other design idiosyncrasies, top speeds, efficiency etc. as I progress through the build.
 
Here are the spoke calculations for the Q128C-135mm in am Alex DM18 700c wheel

To center wheel about the dropouts, I need a 7.75mm offset for dishing according to the schematics. Plugging the values into the ebikes.ca spoke calcuator, I get:

Edit: I've opted for a two cross build





I put the left elbow in and the right elbow out because it seemed to improve spoke tension ratio.
 
On feb 29th, I registered at BMS Battery and I was soon emailed by a couple of sales agents. On March 3rd, Taking motomech's advice to establish good communication, I contacted Suga from BMSB by email with my wishlist.

She responded later the same day to say my parts list was compatible and to check the quote, which included discounts slightly better than their kit prices. I had two chargers on the quote, which was partly my fault, as I’d asked for the battery-charger combo and later said I’d need a charger. I emailed her back on the 4th with the corrections, added a brake lever cut-off to the order and asked for a revised quote.

She emailed back later on March 4th with the revised quote, which was correct.

On March 5th, I placed the order, paying the quote by paypal; I emailed her to say I’d placed the order and asked her to ship to my work address by Fedex. She responded early on Mon March 7th to say she’d received the payment and that the goods were in production.

On March 17th, I was surprised to receive the two packages at work, as I had not been notified the order had been shipped. However, everything was exceptionally well packaged and they shipped me the right stuff:
- Q128C-135mm 500W Rear Driving EBike Hub Motor, 36V 201RPM
- S12S 500W sinewave controller
- LCD-3 for S-series controllers, black
- PAS--Pulse Pedal Assistant Sensor with 12 PCS Magnets
- Pair of EBike Torque Arms, M12
- Thumb Level Throttle
- Brake cutoff
- 48V11.6Ah Bottle-09 Panasonic Battery Pack without Controller, Black

All in all, the BMS Battery order was a positive experience, and arrived quite quickly. I’ll be assembling the bike in the coming days and will update as I go.

I hope to cannibalize the brake lever for parts and modify my hydraulics levers to cut off the motor.

I'm having trouble finding a LBS to lace my motor into a 700C Alex DM18 and I’d rather have it done professionally. I’ll lace it myself if need be; I'm not sure if my spoke calculations (last post) are correct?
 
Here's the donor bike, a 2012 Kona Dew Deluxe:
dew_deluxe.jpg

I'm having the wheel laced into an Alex DM18 to match the front wheel. As you can see, the clearance between hub and calliper may be tight:

Kona Reardisc_small.jpg

The disc on the bike is 160mm and the motor is about 144mm diameter. I'm thinking that a 180mm disc brake rotor will allow the calliper to just clear the hub. I plan to place an order for the Shimano Alivio HG300 9 Speed Cassette, post to IS mount adapter, 180mm shimano RT56 disc, Shwalbe Marathon plus tire and spare tubes in time to arrive for the completed wheel build.

Edited Sept 13th 2017 to upload images due to photobucket SNAFU
 
Had a similar issue when recently installing the very same hub on one of my folders with 140mm rotors. Thought about using a dremel, but that would've meant grinding away most of the inner-side adjustment dial. Instead I got an Avid post spacer set and 160mm rotor, which has the added benefit of concealing the hub.

This is my first build, and so far I'm very pleased with it. The Q128C, combined with cellman's 52V pack, puts out plenty of power for my daily commute. In fact, more than I typically need.
 
I'm excited about the possibilities of the Q128C, as this build should have very bike-like handling and feel. My aim is to be able to pedal this bike with no assistance and have it feel much like stock; thus, as light as possible is in order. Being able to keep the cassette in lieu of the clunky freewheel is nice too.

kurtster said:
Had a similar issue when recently installing the very same hub on one of my folders with 140mm rotors. Thought about using a dremel, but that would've meant grinding away most of the inner-side adjustment dial. Instead I got an Avid post spacer set and 160mm rotor, which has the added benefit of concealing the hub.

It's interesting you were able to get the 160mm rotors to fit. My measurements indicate it will be very close at 160mm, and some rubbing will likely occur. The shimano m445 hydraulic disc calipers are a bit clunky and sit deeply into the disc. Since I need to order a rotor anyway, I see no reason not to go to 180mm to be safe; however, a 160mm rotor would do a much better job of hiding the motor IMO.

kurtster said:
This is my first build, and so far I'm very pleased with it. The Q128C, combined with cellman's 52V pack, puts out plenty of power for my daily commute. In fact, more than I typically need.

Congrats on your first build; nice to hear the Q128C is working out for you :)
 
My aim is to be able to pedal this bike with no assistance and have it feel much like stock; thus, as light as possible is in order.

It doesn't work that way. Even a Q100 on a road bike is too parasitic to ride with the power off. One wouldn't think that 10 pounds and a free wheeling motor wouldn't have such an effect, but it does.
 
motomech said:
My aim is to be able to pedal this bike with no assistance and have it feel much like stock; thus, as light as possible is in order.

It doesn't work that way. Even a Q100 on a road bike is too parasitic to ride with the power off. One wouldn't think that 10 pounds and a free wheeling motor wouldn't have such an effect, but it does.

Consider my bubble burst :oops: That being said, it will be interesting to see for myself how much of an effect the Q128C has on pedalling effort unpowered. I know from experience that it is possible but unpleasant to pedal my HS3540 a few km unpowered - it was still slightly better (and a bit faster) than the walk of shame.


Here is the controller I was sent:

S12S controller cables_small.jpg
As you can see, it is labeled as an S12S controller. The wires do not match those of the S12S, and it appears to have the cruise and EABS lines as per the S12SH pinout. I'm guessing there is nothing to worry about, as their pinouts are likely ancient and no longer reflect their controllers. I'll know soon enough when I hook it up :eek:

They were having a sale at chain reaction cycles, so I placed an order for the stuff I need to complete the wheel and modify the rear rotor.

View attachment 2
S12SH pinout.jpg

I'm definitely going to upgrade the connectors for the power and phase wires.
 
It's been awhile since I have used BMS B Sine wave controllers, but something doesn't look right.
I don't see a Hall connector.
The Hall will have 5 wires: Red, blk, yellow, Blue, and green, same as the display.
As I recall, the display wires are very thin and it uses a female JST style connector.
The Hall wires are thicker and it uses a male Molex that the pins need to be installed.
I may be confusing the SO6S controller here, but I'm pretty sure there should be two sets of Blk, Red, Yellow, grn. and blu,
Maybe you can post a new thread concerning the S12S connectors and some of the guys currently using them can chime in.
It's very strange to me :roll:
 
Golyo said:
molybdenum said:
I put the left elbow in and the right elbow out because it seemed to improve spoke tension ratio.
You will have both in and out elbows, otherwise you cannot cross them.

Thanks for your suggestion; come to think of it, I've bought hubs mounted in cheap rims and noted how the spokes bent around each other for the reasons you mention above. I've little experience at wheel building and I'm short of spare time, so I'm getting the wheel professionally built at the best ebike place on the planet :D


motomech said:
It's been awhile since I have used BMS B Sine wave controllers, but something doesn't look right.
I don't see a Hall connector.
The Hall will have 5 wires: Red, blk, yellow, Blue, and green, same as the display.
As I recall, the display wires are very thin and it uses a female JST style connector.
The Hall wires are thicker and it uses a male Molex that the pins need to be installed.
I may be confusing the SO6S controller here, but I'm pretty sure there should be two sets of Blk, Red, Yellow, grn. and blu,
Maybe you can post a new thread concerning the S12S connectors and some of the guys currently using them can chime in.
It's very strange to me :roll:

I'm quite sure these are the hall sensors, though they're not in a Molex connector; it is hard to see the 6P plug in my lousy photo from the previous post. Here is a better quality closeup photo with the 6P controller connector (right) connected to the motor cable (left). The three phases are protruding from the motor cable next to the halls.

From the pinout, the black should be ground, and the red +5V; the halls are A:blue, B:Green, C: yellow. What is unclear is what the white wire is doing there; I don't see this on any of the controller images, nor in any of the schematics. More concerning is the unexpected extra wire connectors (EABS and cruise?), which only appear in the S12SH schematic.

Hall wires2_small.jpg

I have a few more things to look into but I think your suggestion of a new thread is a good one. I'm wondering if opening it up and examining the innards would reveal the controller type?
 
White wire is usually the speed sensor connection. It could be internal, but many times it needs to go to a separate external speed sensor on the wheel. Does it connect to a nother white wire going into the motor?
otherDoc
 
docnjoj said:
White wire is usually the speed sensor connection. It could be internal, but many times it needs to go to a separate external speed sensor on the wheel. Does it connect to a nother white wire going into the motor?
otherDoc

That's a very good point. Looking into it, the Q128C has an internal speed sensor. The controller is also equipped with a connection for an external speed sensor that mounts on the wheel, which I'm not using.

Indeed, the halls and white wire all connect through the motor cable to the motor. Mystery solved.

Now I just need to confirm they sent me the right S12S controller and not a mis-labeled 35A S12SH version.
 
molybdenum said:
motomech said:
My aim is to be able to pedal this bike with no assistance and have it feel much like stock; thus, as light as possible is in order.

It doesn't work that way. Even a Q100 on a road bike is too parasitic to ride with the power off. One wouldn't think that 10 pounds and a free wheeling motor wouldn't have such an effect, but it does.

Consider my bubble burst :oops: That being said, it will be interesting to see for myself how much of an effect the Q128C has on pedalling effort unpowered. I know from experience that it is possible but unpleasant to pedal my HS3540 a few km unpowered - it was still slightly better (and a bit faster) than the walk of shame.


I don't know about that. I have a couple of q100 builds (road and mountain), and riding them with a dead battery is just fine. The bikes weigh about 30lbs each with motor and battery, so maybe that is the difference. In the 10-15mph range, I'm quite happy riding without the motor.

And yes, a healthy rider on a light road bike is tons of fun. Its a lot different than the mountain bike that weighs about the same, and my range is about 30% farther on the road bike (speed is similar). It does kinda freak driver's out when I'm on a normal looking road bike doing 25-26mph...
 
I finally got around to the build.



20160507_201818_small.jpg

The Q128c is laced into a 700c Alex DM18 mounted with a Schwalbe Marathon Plus. I upgraded the disc rotor to shimano RT66 180mm to allow clearance and added a Shimano Alivio HG300 9 Speed Cassette. Amazingly, the wheel slipped easily into the dropouts with the 9 speed cassette and washers on both sides. The disc rotor needed no shims and the calipers needed absolutely no realignment.

I stuffed the controller and wire ratnest in a vented canvas bag. I'm hoping that at the low power levels I'm running, it doesn't get too hot. I'll monitor the temp and move it under the bag if it's a problem.

Controller bag_small.jpg

Torque arms on both sides. Sept 13th 2017 edit: Cut stainless steel torque arm to fit dropout and used DP420 epoxy adhesive to attach permenantly, as BMSB torque arms had too much play and the wheel came out.

picture to come

The BMSbattery order was perfect except they sent me a left handed thumb throttle; turns out, this arrangement fits the handlebars better anyway. I'll post my thoughts on the performance when I get a chance to test it. Tomorrow, I plan a 26 km round trip.
 
The torque arm and the axle nut are too far out on the axle.
The TA should be clamped against the bottom of the chain stay and the nut should be inboard of the wire exit slot.
Do you have the fat washer/spacer in there? I think you need to replace it with a reg. flat washer.
Remember, when it's right, the wire should exit downward with a loop to prevent water ingress.
Then you should be able to fit the plastic end cap.
The BMSbattery order was perfect except they sent me a left handed thumb throttle; turns out, this arrangement fits the handlebars better anyway.

I don't think BMS B. sells a left-hand thumb throttle. I just flip the reg. thumb around when I mount it on the left and I suspect that is what you have done.
If you like the thumb on the left, you would have really liked the LH half twist i recommended you get.

Do you think the motor would have fouled the original brake disc/caliper?
Looking forward to the performance report.
 
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