Stealthy 2wd q100/q85 build?

[Pongu]

Hi,

I'm a total ebike noob, a less than mediocre electrician/mechanic and english isn't my first language, so please bear with me!

I would like to utilize two geared mini hub motors, because I would like the bike to be as stealthy as possible for several reasons: 1) It will be above legal limits in Sweden, it better look like a normal bicycle from some distance. 2) I don't want to get it stolen. 3) I want to fly past fellow cyclists and have them think a human being can actually go that fast on a mountain bike.

If I get the Gary Fisher hard-tail mtb I'm considering (I may test ride it tomorrow), the plan is to add a 328 RPM Q100C (cst) in the rear and a 201 RPM Q85 in the front. Two S06S controllers, one for each motor. 36v battery capable of supplying 14+14A. The idea is to have the slower motor help in intersections and hills, ie supply torque, while the fast one helps raise the max speed so I get to work faster in the morning. There a very few hills and they aren't very steep.

Can I connect the slow Q85 to the PAS so it assists when I start pedaling and the fast Q100C to a thumb throttle only so I can choose when to activate the Super Turbo Ultra Nitro Power Boost?

Would I need some sort of on/off switch to turn off the Q85 once I have reached cruising speed (if I want to keep pedaling)? I guess a Cycle Analyst would work as an expensive switch to shut off the slower motor above a certain speed, when it starts to become useless.

What do you think?Are these ideas feasible at all..?

Regards,
Pontus

 

[Nobuo]

If you pedal at the same speed of the motor it won't consume too much power, so it is not really needed to switch it off, but yes you could add a switch (powerlock wires on the controller) to the controller.
if I would do that, I would also connect the throttle to both controllers, so in case I want to go full electric power I am able to.

cheers

 

[motomech]

Hi,

I'm a total ebike noob, a less than mediocre electrician/mechanic and english isn't my first language, so please bear with me!

I would like to utilize two geared mini hub motors, because I would like the bike to be as stealthy as possible for several reasons: 1) It will be above legal limits in Sweden, it better look like a normal bicycle from some distance. 2) I don't want to get it stolen. 3) I want to fly past fellow cyclists and have them think a human being can actually go that fast on a mountain bike.

If I get the Gary Fisher hard-tail mtb I'm considering (I may test ride it tomorrow), the plan is to add a 328 RPM Q100C (cst) in the rear and a 201 RPM Q85 in the front. Two S06S controllers, one for each motor. 36v battery capable of supplying 14+14A. The idea is to have the slower motor help in intersections and hills, ie supply torque, while the fast one helps raise the max speed so I get to work faster in the morning. There a very few hills and they aren't very steep.

Can I connect the slow Q85 to the PAS so it assists when I start pedaling and the fast Q100C to a thumb throttle only so I can choose when to activate the Super Turbo Ultra Nitro Power Boost?

Would I need some sort of on/off switch to turn off the Q85 once I have reached cruising speed (if I want to keep pedaling)? I guess a Cycle Analyst would work as an expensive switch to shut off the slower motor above a certain speed, when it starts to become useless.

What do you think?Are these ideas feasible at all..?

Regards,
Pontus

Been there, done that.
I'm not going to go into much detail here, you can read my posts(start with links below), but here some things I have found.
Forget the Q85. The Q100 is so tiny that it is pointless to go with it.
The best version of the Cute is, far and away, the "H" model. It is thought that it has stronger magnets. At any rate, on the same battery and controller, it makes at least 20% more power than the standard Q100.
But it doesn't come in a CST version, so it should be frt. mounted.
(Assuming your bike has 26" wheels, a 328 motor is too high speed and will not be very efficient. The only other speed wind for the CST is 201. That means a 48V battery to get decent road speed. For these reasons, I reccomend the 260 mid-wind on the frt.)
It doesn't sound to me that you meed 2WD, start with a single motor and I'm sure you can get all the speed you want while still climbing the hills you describe.
Your real decissions are what motor wind (201 or 260), what voltage and controller.
With 201 wind motor, 26" wheel, and 36V battery=27 Kph.
Q100H 260 Wind motor=31 Kph
Add 4 to 5 Kph for 48V.

SO6S with SLCD-3 display is not very stealthy and two would be impossible. While the controller is tiny, this display (which you must use) is large and is obvious on the handlebar. You could use the LCD-1 display, but fior max steath, I wouldn't want anything that lights up on the h.bar.
All you really need is a 6-FET controller with at least 3-speed limiter and PAS.
If you are serious about stealth, use a bike with a dark frame so the wires do not stand out. Pick the motor color to match doner bike hub.
The biggest element that is non-stealthy is the battery of course.
The best/easiest battery to use in the new Li-on "dolphin style" from BMS Battery, but it looks like a battery. The older "water bottle" style are a little better, but they are too big as to blend in.
I use Lipo, which makes very small packs, but I would not recommend it to you.
I would go with a small Li-on pack in a bag.
Search the posts of nader in Germany to see unbelievable stealth bikes.

 

[Pongu]

Thank you both!

Maybe two motors would be unnecessarily complicated!
I understand that 328 RPM won't give me much torque. The idea was to use that motor and light pedaling to keep a fast cruising speed. The 260 RPM motors would be more versatile for sure, but I think I would prefer a high max speed since there are no steep hills and very few stops on my way to work and I'm not afraid to use my legs when needed.
The newish Gary Fisher mtb is light gray, so not very stealthy... There is also a steel frame, decent quality older mtb in great condition for sale in my area, which has the old style gear cluster instead of a casette. That one is blue and might be stealthier.
It might be better to go with the older steel bike, invest in a CA to learn more about ebikes, get a higher torque Q100H for the rear wheel and a better quality controller (FOC was recommended in PM) for higher efficiency and less noise.

 

[d8veh]

Your weight has a big bearing on which motor you use. The Q100H is quite powerful, so if you weigh less than 80kg, a single one might be enough, but it also depends on how fast you want to go.

I've also built 2WD bikes like you suggest and they work pretty well. One of them had a 328 rpm Q100 in the back and a 230 rpm Bafang SWX in the front. Another had two 328 rpm Q100s in it, but I had problems with the controllers overheating because the high-speed motors take the maximum current nearly all the time. I wouldn't recommend that if you have a lot of hills and you're heavy.

On one of my 2WD bikes with two 260 rpm Q100Hs, I have the PAS on the rear motor only and the throttke on both. How you arrange the throttle and PAS doesn't really matter, but for simplicity and stealthiness, I would use a S06S controller with LCD for the back motor, which should be a 260rpm Q100H with PAS only (no throttle). The front should be a 328 rpm Q100 with a simple controller like a KU63 with only a throttle as a boist for your other motor. This will simplify the wiring because you wil only need to connect the brake switches to the rear motor.

With this system, you get good efficiency from your rear motor for normal riding, extra speed when you want it and a lot of extra torque for hill-climbing.

These projects are fun, but you can get just as much much more simply by using a single more powerful motor. The 36v 201 rpm Q128H is still quite small and will give you 32km/h on the road with a 48v battery. You can use the 48v 09 bottle battery that includes a 20A sinewave controller, LCD, etc. This will give you lots of torque from a very neat installation.

 

[Pongu]

Your weight has a big bearing on which motor you use. The Q100H is quite powerful, so if you weigh less than 80kg, a single one might be enough, but it also depends on how fast you want to go.

When I was fit I used to be 85kg. Now I'm more like 78kg!
I should go find a long slope and experiment a little with what speed feels safe and comfortable yet takes me to work in a flash, but I feel 30kph would be a little boring on the long, straight, open passages. More than 40-45kph will probably be too fast.

I've also built 2WD bikes like you suggest and they work pretty well. One of them had a 328 rpm Q100 in the back and a 230 rpm Bafang SWX in the front. Another had two 328 rpm Q100s in it, but I had problems with the controllers overheating because the high-speed motors take the maximum current nearly all the time. I wouldn't recommend that if you have a lot of hills and you're heavy.

Not many hills and the few that exist sre short and not very steep, but I wouldn't want to risk frying the motor, which is why the plan was to use the 328 RPM one for cruising speeds only, to increase the max speed. Hence the plan for a little helper with better torque!
The Q75 can't use a S06S, which is why I thought of Q85 201 RPM, but since the Q100 is small too, perhaps it will be unnecessary to go below that (se the post above!).

On one of my 2WD bikes with two 260 rpm Q100Hs, I have the PAS on the rear motor only and the throttke on both. How you arrange the throttle and PAS doesn't really matter, but for simplicity and stealthiness, I would use a S06S controller with LCD for the back motor, which should be a 260rpm Q100H with PAS only (no throttle). The front should be a 328 rpm Q100 with a simple controller like a KU63 with only a throttle as a boist for your other motor. This will simplify the wiring because you wil only need to connect the brake switches to the rear motor.

I'm very tempted by this idea!
It means I have to go with the older bike (but it seems to be in great condition and steel is always steel) if I want to have the Q100H in the back like you suggest, which I agree would be best since it would be the primary motor. The front 328 RPM motor would free wheel at low speeds and only be there for when the STUNPB (Super Turbo Ultra Nitro Power Boost) is needed on the long flat boring roads. PAS only on the rear motor would work great, since it will always be on and a small LCD for the PAS level etc would be hard to be without.

With this system, you get good efficiency from your rear motor for normal riding, extra speed when you want it and a lot of extra torque for hill-climbing.

It seems to be what I was aiming for, just a little better thought out!

These projects are fun, but you can get just as much much more simply by using a single more powerful motor.

Yes, the backup plan is to throw stealth out the window and get a MAC 1000W kit instead!

Thanks for giving me much food for thought!

 

[motomech]

Which do you want to do, build a stealth bike or a complicated bike with computer displays and buttons and switchs. When someone sees a large screen CA or SLCD-3, they know instantly it's electric.
And if you have a limited budget, and it sounds like you do, why spend all your money on a 2WD you don't need and buy a crappy bike?
A single Q100H on 48V will get you to 37 Kph, which is fast enough to be fun and you might even be able to pedal along with stock gears.
At speeds above that, you really need hyd. brakes and at least good frt. suspension. If the roads are not perfectly smooth, you need rear suspension too.
If you must use 2WD, the only reason to do that is to be able to run two 328's for the highest top speed, like I do. Or maybe a pair of 260's for steep hills or a pair of 201's for dirt riding. But if you start overlapping motor speeds for some reason, you would be better off with a bigger motor.
My 2WD easily goes 45 Kph, but it's a high quality bike and I have rebuilt the wheels with wider rims and tires for stability. I also installed custom gearing to be able to pedal along.
But I have over $2000 US invested.
I also have a bike with a single 260H on the frt. and it is just as fun to ride, for a lot less money and very few people have any idea it's not just a regular bicycle.
I would suggest you put your money in a nice bike to start and you can add a second motor later if you feel the need.
and remember, for 2 motors, you will need a higher discharge battery and they are not cheap nor stealthy. What battery do you have in mind?
The other thing that you may not realise is, to use a 260H rear, you will need to buy a free wheel and the options are not good. To get the 11T sm. gear needed to pedal at 45 Kph plus, you will need to buy a DNP and they are Junk. the other options start with 13T sm. gears and they are cheap units and don't last.

 

[Pongu]

The older of the bikes I was considering is from the late 90's and already has a free wheel instead of a casette. So a Q100H would fit in the rear too. No suspension and a steel frame, which I thought would be good for stability and safety. Then again, if new high-quality 11T clusters are hard to find and the original is 13T, which means I won't be able to pedal at higher speeds, then it may not be the perfect bike to build on. The roads are pretty flat but not perfect. Perhaps I will be shaken to pieces at higher speeds!

I could get an expensive bike (a used cyclocross or something similar that is built to go fast), but I'm afraid it might get stolen. So I would prefer to have a strong, safe bike that flies like the wind, but doesn't draw too much attention when it's parked outside work.

The newish mtb will have a casette in the rear, so that would have to run a Q100C rear or Q100H front.

After having a front wheel unattach itself from the fork at 30km/h (while jumping from the sidewalk onto the road) in my youth, which led to quite a few bruises, I'm a little hesitant to put too much motor on a suspension fork, but I guess a Q100H would still be OK?

So the simplest and most practical choice would be to get a good, modern bike and put a single Q100C in the rear or a Q100H in the front, with some stealthy battery solution and no LCD. But I would need an LCD to get different levels of PAS and at some point a CA would be fun to get more control of what's going on.

Another practical but less elegant choice would be the older bike and a single, pehaps larger motor in the rear, which means less stealth, less pedaling at high speed but an affordable, powerful and simple installation.

Then there is still the temptation of having two small motors as outlined above, but an older mtb may not be able to handle that much speed for the above reasons...

Hmmm... You have given me much to think about! I need to sort out my priorities first and then decide on the bike!

 

[d8veh]

You can get DNP freewheels with 11T top gears. I have them in UK or you can get them from Ebikes.ca if you're in USA or Canada.

 

[Pongu]

I'm going to look at a hybrid bicycle tomorrow. It's black so cables should blend in pretty well. The brand (Crescent) has a good rep in Sweden and it's only a couple of years old, so it should be in pretty good shape.

I'm leaning towards a simpler build... Stealthy and semi-legal. Which means a small geared motor, preferably in the rear. But I'm reluctant to throw out the casette and get a soon to be obsolete screw-in cluster just to be able to mount a Q100H in the rear. So I could either put a Q100H 260 RPM in the front or Q100C (cst) 201 RPM (but boosted to the same speed by 48v on the battery) in the rear. Rear is stealthier. Front gives me a little extra torque and an easier installation, but is a little less stealthy and handling may not be as good as with a rear mounted motor.

Would less than 500W (15 amps at 36v) be OK even though it's on an aluminium fork with suspension? The cousin is in the hospital right now after a bad motorcycle crash and will probably not live... So I feel less inclined to take risks right now.

 

[Cephalotus]

I use a Cute 85 for more than 3 years and it runs well at 36V and 11A. I see no reason why it should be "to small" especially in a dual drive and with a rider actually pedalling?

I recommend to get two fast motors, so the current will be devided on both when going quickly. With your weight and two motors and youself pedaling I see no problem at all going up some hills with that setup.

I also would suggest reading about the mmc-v3 controller from elfKW: http://elfkw.at/produkte/controller/mmc-v3-bluetooth (maybe you need to use google translation)

Buy two contsrollers for your motors and file the switch down to maybe 10-12A maximum. The elfKW will let you programm two setups. Make setup 0 the stret legal setup with 20A peak current and maybe 12A contious current (devided on both motors) and a speed limit of 25km/h (throttle can be programmed to work only with PAS after 6km/ or whatever speed and ist a power controll throttle - highy customable- instead of the chinese speed control throttles).
Make setip 1 your fouvorit setup.

Switch of the bike and it will always start in the legal setup #0. You can set it two your fun setup #1 with a smartphone app (bluetooth, also shows lots of data) or with a (hidden) switch during startup. You also get a programmable (6-9V?) DC output voltage for your lights. I would programme the fun setup at 22A peaks (for maybe 30 seconds, everything is programmable by the way) and 16A continous. At 8A each motor it will be a very efficient setup and almost impossibe to overheat.

16A at 36V at two fast winding 328rpm motors will easily get you to 40km/h if you are willing to pedal a bit...

 

[Pongu]

Thanks Cephalotus!

The programmable controller seems great. But if I make the bike look reasonably unsuspicious and use some good manners and common sense, I doubt I'll be pulled over by the cops.

I bought the black hybrid bike!


Now for a noob question:
If I would get a Q100H for the rear wheel and exchange the gear cassette for the 11T screw-in type freewheel cluster mentioned above, will the derailleur work just as well as it does now or should I stick with casettes..?

If it's best to stick with the cassette type freehub, then my latest idea is to put a Q100C (cst) in the rear and a Q100H in the front, both 201 RPM. With a 48v battery they should spin at 268 RPM right? I liked the idea of having a current limited, PAS controlled main motor rear for everyday use and an extra motor in the front for speed. Since only the current limited rear engine would be punished by hills and city traffic, the front one should be able to withstand unlimited 15 amps by throttle when the long, straight flats get boring right?

Or if a Q100H would be unsafe, I could put a Q85 in the front instead, to minimize the strain on the aluminium fork and maximize stealth.

 

[motomech]

http://endless-sphere.com/forums/viewtopic.php?f=3&t=54043&p=1042846&hilit=enoch#p1042846

Even so, you would be better off running two 260H 260 motors and accepting to substandard performance of the DNP, rather than trying to use different speed winds.

Two 201's on 48V would do 37 Kph together, a little slow, but it would climb very well.

That bike has lots of triangle space for a triangle bag and big battery.

 

[Pongu]

Aarrgh... Compromises!
Dirty mid-motor and Bafang CST thoughts are creeping in!

BTW, thanks for turning me away from the steel fork mtb. After trying out the new bike at high speed on a gravel road full of pot holes, I'm in love with suspension... The difference between locked and active was like night and day!

 

[motomech]

Yeah right.
Mid motor is not stealthy.
Bafang CST is nice and simple.
D8veh doesn't care much for dual 328's but I do.
Zero problems and I am a heavy rider, but use 24" wheels and ride in a flat area.

http://endless-sphere.com/forums/viewtopic.php?f=4&t=40567&start=25

We have been waiting for a Q100 H CST for a while now.
MXUS makes a mid wind CST mini and they are great motors. Slightly larger than a Cute.

 

[tomjasz]

Um, good ideas, but on the right bike a mid is very stealthy. It's the battery that get attention for me.

 

[Pongu]

Yeah right.
Mid motor is not stealthy.
Bafang CST is nice and simple.
D8veh doesn't care much for dual 328's but I do.
Zero problems and I am a heavy rider, but use 24" wheels and ride in a flat area.

http://endless-sphere.com/forums/viewtopic.php?f=4&t=40567&start=25

We have been waiting for a Q100 H CST for a while now.
MXUS makes a mid wind CST mini and they are great motors. Slightly larger than a Cute.

Thanks, I'll have a look at MXUS too!

 

[d8veh]

I've used the small Mxus CST motor. It wasn't very powerful and didn't like more amps. It got quite warm at 19A. One of the sales team from Mxus told me that there's two versions. One has weak magnets and lower grade wire for the Chinese market and the other has higher grade wire and magnets for export. I bought mine from a Chinese stockist. I've no idea which version I had, but probably Chinese market version.

 

[Pongu]

For this bike, I have decided a Bafang BBS01 36v will be the best choice. It will allow me to pedal, but with assistance both for going up hills and increasing max speed on flat roads. And it will be legal, so it doesn't have to be ultra stealthy. But the look will be clean. Black frame, black mid drive, black frame battery. I'll post some pictures once I'm done!

Thanks for all the suggestions though!
They will come in handy when I electro-cute my second bike! It will probably get a front mounted Q100H at some point.

 

[medved]

I'm also thinking about 2wd with two Cute Q100 motors and S06S controllers.
Is it possible to connect two S06S controllers in master/slave mode? So, throttle, PAS, speed sensor, ebrakes and display will be connected to one of controllers and another controller will simply duplicate the current on the other motor.
Or what is the best way to connect it?
Thanks