Considering hub motor build for wife... Few questions

Hello all,

I built myself a hub motor commuter using a 36V 201 RPM Q128CST and a 52V 09/dolphin case battery and its working well for me. I want to build a bike for my wife now but thought I would step down to the Q100 to keep weight down for her a bit and also outright speed will never be a care of hers. My question is can I also over volt a 36v Q100CST motor to 48V or 52V? Or since as I said speed is not an issue perhaps I should just stick to 36V pack instead. While I say speed is not an issue it would be great if our bikes were not too dissimilar and speed. My bike is PAS only and I dont even have a throttle, but I will likely set hers up as PAS & Throttle option.

What do I gain or lose by overvolting the Q100CST to 48V or 52V?

What are the benefits if any of just building her a stock 36V Q100CST setup?

She has a Giant Sequoia Drop Frame bike that I may do the mod on, however its a bit small for her. I am considering selling it and buying the Giant momentum I need street and modding that instead. Sort of on the fence between using what she has or buying new.

Luna has the BBS02 kits with battery for a good price, but leaning toward the hub build like mine for the more bike feel when pedaling when motor is off... But not opposed to the BBS02

Open to any and all advice.

Marc

For my girlfriend, who doesn't shift her bike's gears even when she has them, I built a single speed bike with a Q128 front hub running at 36V and 17A. Since the motor is underworked, I'm confident that she won't cook it by lugging it down at full throttle. Acceleration and climbing are more than adequate and speed tends to top out at about 18mph. Her battery range is so long that she waits for me to charge the thing (take charge?), sometimes a couple of weeks. I can't account for it because it's only supposed to be a 36V 10Ah battery. But I guess it sort of makes sense because her typical round trip is about 2 miles and she doesn't ride it every day.

Anyway, she loves the bike and I love that it's very easy to maintain. If I didn't need to haul things around so much, I'd want my own bike to be more like hers.

The 36v 201 rpm Q100 becomes 260rpm when you run it at 48v, which is a nice speed for the Q100 considering its size and power. At 48v, it gives quite a lot of torque too.

The 36v 260rpm or 328 rpm versions at 48v will most likely be too fast for their power, which means less efficiency and more heat problems.

addicted2climbing said:

Hello all,

I built myself a hub motor commuter using a 36V 201 RPM Q128CST and a 52V 09/dolphin case battery and its working well for me. I want to build a bike for my wife now but thought I would step down to the Q100 to keep weight down for her a bit and also outright speed will never be a care of hers. My question is can I also over volt a 36v Q100CST motor to 48V or 52V? Or since as I said speed is not an issue perhaps I should just stick to 36V pack instead. While I say speed is not an issue it would be great if our bikes were not too dissimilar and speed. My bike is PAS only and I dont even have a throttle, but I will likely set hers up as PAS & Throttle option.

What do I gain or lose by overvolting the Q100CST to 48V or 52V?

What are the benefits if any of just building her a stock 36V Q100CST setup?

She has a Giant Sequoia Drop Frame bike that I may do the mod on, however its a bit small for her. I am considering selling it and buying the Giant momentum I need street and modding that instead. Sort of on the fence between using what she has or buying new.

Luna has the BBS02 kits with battery for a good price, but leaning toward the hub build like mine for the more bike feel when pedaling when motor is off... But not opposed to the BBS02

Open to any and all advice.

Marc

Click to expand...

I've built a couple of "assist bikes" based on the Q100.
My current one is along the lines of what you are thinking about. A Q100C in a 26" wheel powered by a LiPoly battery pack that is close to a 48V battery;



It does 18 to 19 mph flat out and on a 48 V batt. I suspect that would be 19 to 20 mph.
I think the one thing I can suggest concerns the controller. I'm thinking she probably doesn't need or care about a sine wave controller/display w/ all the features, info and buttons. I'm using a simple Square wave, 3-speed controller from elifebike. It works well on a low-powered, low speed system. 3 speeds covers the speed range w/out any gaps and when changing PAS speeds, there is little motor "surge" as the system moves up to the next speed. The 810 display is sm. and simple, yet provides on/off, the 3-speed adjustment and a 3 LED "fuel gauge". There is a slight delay when one starts to pedal, which the sine wave doesn't have, but one adjusts to it.
I use the larger 9-FET 17 Amp controller because I have it in a bag, but they now offer a sm. 6-FET unit that works on 48 V. They are avail. at ELB's ebay store and are very reasonably priced.

http://stores.ebay.com/diyebikestore/

Been tempted to try the Q100CST on my wife's trike. She has a Tongsheng mid drive, but wants less noise. We already have a CA3, Thun & Phaserunner and I've been considering mounting a spare MAC10, but its a bit heavy and she has a 36V 8AH battery.

Maybe motomech has one of these Q100CST's I could have a peek at?

I'm near Orange Grove & First....

Triketech said:

Been tempted to try the Q100CST on my wife's trike. She has a Tongsheng mid drive, but wants less noise. We already have a CA3, Thun & Phaserunner and I've been considering mounting a spare MAC10, but its a bit heavy and she has a 36V 8AH battery.

Maybe motomech has one of these Q100CST's I could have a peek at?

I'm near Orange Grove & First....

Click to expand...

Sure, no prob.
I have the bike pictured above you can look at/ride.
And
I also have a Q100H (260) on the frt. of my 2WD;



Same Voltage and controller I run on the Q100C, but it feels much more powerful.

I also have a lightly used Q100C (328) which would be good for a single, small wheel driver trike.

https://endless-sphere.com/forums/viewtopic.php?f=9&t=84796&p=1240933&hilit=motomech#p1240933

I'm at Speedway and Swan, retired and here most of the time.
Sorry, no phone at the moment, but you can PM me for my Email

I have two Q100c CST motors , both 201 rpm wind, one laced up to a 650b rim, and the other laced to a 700c rim
I am mostly using the 700c wheel these days.

Depending on if I am going on mostly flat ground or a few slight hills I will use 2x 6s lipo's, or , 2 x 7s lipo's ( really 4 so I am first putting them in series, then connect them to a home made parallel wire harness to the controller.
So in other words I am using a 12s pack or 14 s pack.
It works perfectly, and I am using a little 6 fet controller that was sold as a 48 volt controller, but looks exactly like the 6 fet 36 volt controller from BMS Battery.

It will go up to 20-22 depending if the road is smooth and no wind.
and
Likes to cruise at around 16-17 mph.

addicted2climbing said:

I want to build a bike for my wife now but thought I would step down to the Q100 to keep weight down for her a bit and also outright speed will never be a care of hers. My question is can I also over volt a 36v Q100CST motor to 48V or 52V?

What do I gain or lose by overvolting the Q100CST to 48V or 52V?

Open to any and all advice.

Marc

Click to expand...

Im looking to buy the battery pack with the integrated controllers and they say they work with motors with internal speed sensors. I know my Q128 has an internal speed sensor, but its not mentioned on the Q100 specs. Does the Q100 have one? I want the integral controller for the easier and compact wiring. Also the connections are waterproof, seems if the Q100 does not have the integral speed sensor than the connectors from the controller are not compatible and Im guesssing it has a different pin count. Can someone confirm this? For this reason alone the Q128 may be back on the list but Id love to save weight on her bike and go Q100 as a first choice...

Another option is buy a Q128C CST in 36v 201rpm and also the 36V rear rack battery with controller and all the wiring is compatible. She would have a lower top speed than my Q128 setup, but perhaps the larger motor may still give her more Torque when we are on hills... Her bike is a drop frame women's layout and the rear rack system may be a better option as fitting a battery on the drop tube may be tough since its not completely straight. Downside with this layout is all the weight is on the rear, but its all pretty light anyhow so may not be a big deal. Anyone on here have one of the BMS rear rack battery Case-02 setups? If so how do you like it?

Marc

Yes, all the versions of the Q100 now come w/ an internal speed sensor(white wire).

Wives vary. Mine love to bike ride, but NEVER more than about 5-8 mph. So for her, a 500w bike is scary fast.

You have to be the judge of what will suit your wife. Easy to give her more speed and power later, but impossible to get her ass back on the bike if your first try is scary to her.

motomech said:

Yes, all the versions of the Q100 now come w/ an internal speed sensor(white wire).

Click to expand...

OK great to hear. So I guess the waterproof wiring harness I used on the Q128 should work on the Q100. Suppose my only remaining question is if anyone has purchased the rear rack integrated battery setup. On my bike I did not want it since I already had a heavier Q128 and did not want too much on the rear wheel. however in this setup with the lighter motor it may be OK. Plus she may have a front basket with stuff in it as well to offset some weight.

dogman dan said:

Wives vary. Mine love to bike ride, but NEVER more than about 5-8 mph. So for her, a 500w bike is scary fast.

You have to be the judge of what will suit your wife. Easy to give her more speed and power later, but impossible to get her ass back on the bike if your first try is scary to her.

Click to expand...

Yes I want to keep it low power. So another option is I could buy her a new bike with a steel front fork and put the motor on the front. My only concern is she is used to having a front fork so the ride may be a bit harsh. Does riding a front driven motor feel wierd. If the bike feels uncertain to her she may not like it.

Im now pretty sure I am going with a Q100h on the front with the battery on the rear rack. Motor and battery will be 36V so this will be a low power setup and maybe will help with the battery weight on the rear being 36V and less cells. My question that nobody has answered is does a front driven setup feel odd for a casual bicyclist. If the bike feels weird to her or scares her than she wont want to ride it. But if people who have built/ridden one say its a non issue than its the direction I am going. Bike has a curved top tube so battery will have to be on the back and id hate to also put the motor back there as well if front drive is easy to adapt to for an inexperienced rider.

The Overpriced Farady is doing it so im thinking its a non issue

Thanks,

Marc

I built an frt. powered Q100 on 36 V when I lived in a beach town in Mex. I called it my "boardwalk bike" and I wanted it to be about as low-powered as practical because of the people milling around. It would do about 16 mph and below that speed felt like a normal Q100 build(but not a Q100H on 48V build). The frt tire wouldn't spin unless on wet grass. And I have never felt the Q100 was heavy enough to be a prob. on the frt. In fact, the only mishap I have evr had on any of my frt./Q100 builds was when I was standing next to the bike talking to someone and leaned against the thumb throttle The wheel was crocked and it launched off sideways. I grabbed the bars and it pulled me along a few feet, but didn't crash. It was a bit embarrsing though.
I would say, either bike or trike, she won't have concerns w/ a Q100 on 36 V and 10 to 15 Amps. Actually, I would go further and say, she will luv it.

motomech said:

I built an frt. powered Q100 on 36 V when I lived in a beach town in Mex. I called it my "boardwalk bike" and I wanted it to be about as low-powered as practical because of the people milling around. It would do about 16 mph and below that speed felt like a normal Q100 build(but not a Q100H on 48V build). The frt tire wouldn't spin unless on wet grass. And I have never felt the Q100 was heavy enough to be a prob. on the frt. In fact, the only mishap I have evr had on any of my frt./Q100 builds was when I was standing next to the bike talking to someone and leaned against the thumb throttle The wheel was crocked and it launched off sideways. I grabbed the bars and it pulled me along a few feet, but didn't crash. It was a bit embarrsing though.
I would say, either bike or trike, she won't have concerns w/ a Q100 on 36 V and 10 to 15 Amps. Actually, I would go further and say, she will luv it.

Click to expand...

Thanks Motomech,

This was just what I needed to hear. I live a mile away from Pure Cycles main office in Burbank and I plan to go have a look at their city bike. Been going back and forth with decision on Priority classic plus step through and the Pure City. Im leaning toward the Pure CIty since its the nicer looking bike (ie pretty to the wife) and being local if I have issues I can get help. The mod likely voids the warranty, but been chatting with them and they seem interested in seeing this conversion. My only con with this bike is its 32lbs so I am already starting off on the heavy side and was hoping to be under 40lbs.. But maybe I wont be too far off.

I like the Priority belt drive and the fact that its 26lbs in her size so I could hit that 40lb mark for sure. What I dont like is a coaster brake in their special nexus hub on an electric bike. She will likely always ride in the 12 to 15mph range but I remember my coaster as a kid being a pain in the butt and not very easy to modulate.. Ie skid a lot.

The Pure city comes in Nexus 3 speed or 8 speed derailer. I like the simpliciity of the 3 speed nexus hub, but being a low powered PAS bike we will pedal a lot and I fear she will always be in a gear less optimal with only 3. Also with power, im guessing she will max out the resistance on the pedals quickly on the Nexus. Than again she likely wont go that fast but that is just a guess. Your thoughts on pros and cons of nexus 3 spd vs 8 speed with a derailer. She is not the techincal type so will adapt to whatever I build her but have no experience on the Nexus hubs so unsure if they are fun to ride or not.

My Q128 bike has an 1x11 speed setup and I had to buy a larger crank gear but other than that one change its been very reliable. Its right around 40lbs I think.

Marc

Hello All,

I have been a bit preoccupied with work to get this build going. I spent the weekend test riding bikes for my wife. She is 6'1" and only 3" shorter than me so I figured I am close enough. Downside is most women specific bikes end at 5'10" but many are fine for a bit taller. I tried just about every Dutch geometry type city bike I could find: Pure City, Public, Electra, Raleigh & Linus. I also tried a few Mixte types as well. The Mixte would be perfect since my wife is French but of the ones I found they felt a bit small. Public has a nice one but could not find one to try. Also Linus has one in a Large but can only find Medium locally. Price is also an issue and I found the Pure City for $249 and at one bike shop I found a public C7 and the guy will let it go for $275 out the door. I am leaning toward the Public C7 since its red, rode nice and has a color matched rack. I hated how the Linus Dutchi felt. If money were not an issue I'd likely buy the Public Mixte. Anyhow, Below I have a few pics of the bikes with some simple configurations for the battery. I imported the jpegs into Solidworks, Scaled them until the wheel were 622mm and then sketched a simple battery and Q100. I decided against the rack integrated battery and will use a shark pack instead. One reason is I can use the shark pack on my mtn bike when I convert it in the future.

Public C7:
This bike has a rear derailer and with that it gives me options to put the motor on the front or rear. The image below does not have the rack but the bike I can buy does. I was thinking to mount the battery on the rack and then either hide it behind the cassette or put it on the front but it will be more noticeable. I'm on the fence with either configuration. On the front shares the weight front to rear, but this setup will be light and if the motor is on the back only the battery will be seen and if I add panniers I may be able to hide battery. Or place it in a basket on the back. Bike cost $275, BMS $585 for a total of $860

View attachment 1



Public M7:
This bike has a nexus rear hub so Q100 would go on the front. The frame has room for the battery. as I said if money were not an issue Id go this route for sure. Bike cost is $765 than the items from BMS are $585 for a total of $1350






I also really liked the Electra loft but the curve of the frame would not allow the battery to fit inside it. I would choose the Public over this if I were going to buy a more expensive bike.

Last question in regards the the items from BMS. When I converted my bike I bought a Q128Cst 201rpm at 36V and a 52V battery and 48V controller. Dolphin case setup with waterproof wiring. I did this to overvolt the Q128 to get closer to 260RPM. I see that the Q100 is available in a 260 RPM version so unsure if I should just stick to a native 36V setup on her bike. Or buy the Q100 in 201V and buy the 48V pack and controller. I'd likely prefer 48V if I wanted to use her pack on a mountainbike, but my first priority would be what is best for this build. If I can re purpose the pack I will but its not needed. My mtn bike may not even be convertible as there is not much room in the triangle anyhow. So my question is what are the pros and cons of each motor setup mentioned above.

Thanks again for all the help everyone..

For the last several years, all my frt. wheel/motor ASM's have been Q100H "201's" and "260's" and I can swap the two back and forth, even on the same bike. And, except that the 260 is a couple mph faster on the same pack, I never really felt there was much difference between the two. I can climb as steep a hill on the 260 as I can w/ the 201, so I don't really see any advantage to using the 201, unless maybe for off-road where every last "inch" of torque is desired.
I use LiPoly and the times I have used 9S or 10S (33V or 37V) was as much because I have the bricks laying around to configure those size packs. Like 201 vs 260, I don't see much reason to go 36V pack over 48V pack. If you have the possibility to make a 48V pack multi-usage, I would say go w/ it and limit her bike w/ the controller.

My mtn bike may not even be convertible as there is not much room in the triangle anyhow.

Click to expand...

Go LiPoly :lol:
This weekend, I reconfigured the main pack on my GT IDrive and added a sm. aux. pack;





The sm. over-the-frame saddlebag holds 10,4000 mAh of 44 Volts and the aux bag holds 4,000 mAh of the same, for a total system capacity of 14,4000 mAh's. And I still have my "bottle battery", which would add another 4,000 mAh.

There is ALWAYS room for LiPoly!

Hey Motomech.

Thanks for the reply. As usual a few more questions..

Like 201 vs 260, I don't see much reason to go 36V pack over 48V pack. If you have the possibility to make a 48V pack multi-usage, I would say go w/ it and limit her bike w/ the controller.

Click to expand...

So for her setup your suggestion is I go 48V and buy a 36V 260 Q100 motor? Im worried about this option getting her close to 300 rpm per volt.. Or 48V and 36V 201 motor? Any issues over volting the Q100 like I am doing the Q128? I will be using the 18amp integrated controller in the Shark case BMS sells. As for controller limiting I do that in the Top speed cutoff value on the LCD?

Now for your advice on configuration on the dutch type bike? Would you go front drive or rear? Even if I buy pannier bags to hide the battery, I don't foresee her adding much weight in them so a rear battery and rear motor might be the cleanest look both wiring wise and convenience wise. On the flipside the Dutch type geometry seems to be so upright that the rider weight is more biased to the rear axle so it may make sense to buy the front motor to put some weight back on the front. My only concern is the front fork looks a bit thin. It is High Ten steel so it should be fine and the Q100 is small but just worried about a failure on the front and consequences (wife never bikes again) whereas with the motor on the rear the failure would be less of a worry. Public does sell an electric mixte setup with all the weight on the rear and the motor is 3x the size and weight of the Q100 and the weight on the rear seems not much an issue.

Take care,

Marc

I think you are starting to overthink this. The Q100's middle names are "worry free".

I will be using the 18amp integrated controller in the Shark case BMS sells. As for controller limiting I do that in the Top speed cutoff value on the LCD?

Click to expand...

That's a sine wave controller so it limits performance by CURRENT, so when the top speed is limited, the whole performance envelope is limited. Just what you want for her. Depending on which display is used, there will be some buttons either on the display or a remote to scroll up and down.

So, given that the bike's performance can be reined in, I would get the components that offer the best performance, the 260H and a 48V batt. That way, if she loses interest in the whole thing, you have the best toys to play with :lol:

Now for your advice on configuration on the dutch type bike? Would you go front drive or rear? Even if I buy pannier bags to hide the battery, I don't foresee her adding much weight in them so a rear battery and rear motor might be the cleanest look both wiring wise and convenience wise. On the flipside the Dutch type geometry seems to be so upright that the rider weight is more biased to the rear axle so it may make sense to buy the front motor to put some weight back on the front. My only concern is the front fork looks a bit thin. It is High Ten steel so it should be fine and the Q100 is small but just worried about a failure on the front and consequences (wife never bikes again) whereas with the motor on the rear the failure would be less of a worry. Public does sell an electric mixte setup with all the weight on the rear and the motor is 3x the size and weight of the Q100 and the weight on the rear seems not much an issue.

Click to expand...

I'm not even sure what a "Dutch bike" is, let alone understand your question.
But I have never seen a pair of steel forks that a Q100 couldn't be safely mounted. Buy 2 pr.s of torque arms when you place your order, even if you don't use them both they are good to have.

motomech said:

I think you are starting to overthink this. The Q100's middle names are "worry free".

I will be using the 18amp integrated controller in the Shark case BMS sells. As for controller limiting I do that in the Top speed cutoff value on the LCD?

Click to expand...

That's a sine wave controller so it limits performance by CURRENT, so when the top speed is limited, the whole performance envelope is limited. Just what you want for her. Depending on which display is used, there will be some buttons either on the display or a remote to scroll up and down.

So, given that the bike's performance can be reined in, I would get the components that offer the best performance, the 260H and a 48V batt. That way, if she loses interest in the whole thing, you have the best toys to play with :lol:

Now for your advice on configuration on the dutch type bike? Would you go front drive or rear? Even if I buy pannier bags to hide the battery, I don't foresee her adding much weight in them so a rear battery and rear motor might be the cleanest look both wiring wise and convenience wise. On the flipside the Dutch type geometry seems to be so upright that the rider weight is more biased to the rear axle so it may make sense to buy the front motor to put some weight back on the front. My only concern is the front fork looks a bit thin. It is High Ten steel so it should be fine and the Q100 is small but just worried about a failure on the front and consequences (wife never bikes again) whereas with the motor on the rear the failure would be less of a worry. Public does sell an electric mixte setup with all the weight on the rear and the motor is 3x the size and weight of the Q100 and the weight on the rear seems not much an issue.

Click to expand...

I'm not even sure what a "Dutch bike" is, let alone understand your question.
But I have never seen a pair of steel forks that a Q100 couldn't be safely mounted. Buy 2 pr.s of torque arms when you place your order, even if you don't use them both they are good to have.

Click to expand...

Ok sounds great will go 36V Q100h in 260 and a 48V battery pack. Rear mounted motor makes sense just in case she decides she hates it and I will have more chance to repurpose a rear motor wheel than a front motor.

I just noticed the bike has a single wall rim. Unsure if it has eyelets. Lets say its a simple single wall 700c wheel, any issues using this with new spokes and a Q100h? Or i can ask to buy a matching double wall rim that hey use on another bike. On my Q128 I bought a ebike rim from Dtswiss, but would prefer to use the stock rims painted in red.

Marc

No, you can't use a single wall rim w/ a hub motor, even a sm. one like the Cute.

Just curious--why not?


They're not as strong as doublewall, but there's nothing physically preventing it, and if your normal riding doesn't cause problems with singlewall, and you use the same gauge of spokes the singlewall was designed for, I can't think of a reason it wouldn't work.


That said, I don't even like singlewall rims for regular bike wheels, because I'm hard enough on wheels that they don't last as long as doublewall (and they flex more in sideloads with heavy cargo on them), bending them sooner than doublewall in my application.

motomech said:

No, you can't use a single wall rim w/ a hub motor, even a sm. one like the Cute.

Click to expand...

Thanks motomech,

I will look to see about buying a different rear rim. I asked the company to sell me a Double wall in red but they wont. Seems all replacement rims will be in silver and I may as well just use the same DTSwiss rim i used on the Q128. BMS has a wheel in rim option, but the shipping is around $160 and I can buy a nicer rim and have it laced for less than that. I still have the rim I did not use on my Q128 build. Its a 32 hole and the Q100 is available in 32 hole if I go with the CST version but than its 201rpm again.. I am pretty sure my rim on hand is double wall. May just end up using that.

Thanks again,

Marc

The Pure City has deep double wall rims, but it is not eyleted? Will this work or are eyelets and requirement as well?

Marc

There are hardly any deep section rims with eyelets. In practical terms, you can either choose deep rims or eyeleted rims, but not both. Eyelets are more of a convenience feature than a necessity, serving as a consistent bearing surface for the spoke nipple and offering some protection against cracking at the rim holes.

Normal shallow section rims with eyelets are easier to build and service, and easier to find in wide sizes to support wide tires. Deep section rims can be stronger per weight and potentially can carry heavy loads more reliably.