2WD (Two-Wheel Drive) FAQ

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chas58
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Re: 2WD (Two-Wheel Drive) FAQ

Post by chas58 » Oct 17, 2014 2:51 pm

motomech wrote:
sange wrote: As I said before, expect a top speed for two 328's @ 36V to be around 40 Kph.
I agree, that is what my bike does...
25^3 bike: 25 lbs, 25 mph, 25 mile range.
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https://endless-sphere.com/forums/viewto ... =3&t=49691

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Re: 2WD (Two-Wheel Drive) FAQ

Post by arkmundi » Oct 17, 2014 4:28 pm

Thanks for an informative discussion of 2WD. Comes up in context with the MXUS, motor wind, no additional torque discussion. Framed as a trade-off between speed and torque, where torque is often needed to contend with hills. My purchase of the 3000 watt MXUS is a need for sufficient speed, 30-35 mph, to flow and blend with urban traffic. A rear mount motor. My current ride has a Heinzmann 500 watt 36V geared front-mount motor. May keep it as is, but considering, take that and mount on my new Trek Shift 3 along with the MXUS. The Heinzmann gets me up hills just fine and home city is nestled in the hills of central Massachusetts. So maybe a little extra kick up the hills. Motor & controller are light enough. Tie into the battery, which will be a 72V A123 AMP20 pack in two 36V sections, mounted pannier style on a back rack. Configuration lends itself to 2x serial for 72V or 2x parallel for 36V.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by sange » Oct 19, 2014 3:37 am

Hello D8veh,
what is the proven maximum current for a S06S with a soldered shunt mod?
Thanks.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by d8veh » Oct 19, 2014 6:09 am

Most of these Chinese 6 FET controllers can go to about 20A, but it depends also on your motor. A high speed motor will draw the maximum current most of the time. You have to bear in mind that the S06S is only rated at about 7A. It'll overheat if you run it continuously much above that. Obviously, if you have it out in the air-stream, it has a better chance. The KU63 controller used to be my preferred 6 fet one because it's very robust and flexible. They overheated and cut out when I used them on my twin 328 rpm Q100 bike at 15A each.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by drew12345 » Oct 25, 2014 10:01 am

Has anyone done SingleTrack with 2wd? I'm wondering how it would handle and would motor overheat with all the stop and go and rolling hills.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by fellow » Nov 13, 2014 6:17 pm

sange wrote:Hello D8veh,
what is the proven maximum current for a S06S with a soldered shunt mod?
Thanks.
I assume that you mean S06S with Frankenstein mod (=changed mosfets). The original mosfets will smoke on default (7A cont, 14A peak) shunt, sooner or later.
Here is my shunt at 19A, 54.6V, irfb4110pbf Frankenstein S06S mod used on oil cooled Q100H 201rpm:
Image
The highest I've tested is 20A, its about 1-2mm more on the shunt. Current record is held by Snickers here on endless, 53A:
Image
I believe his controller died after that, if my French servs me correct. His mod involved heavy modification of shunt, and other components besides the mosfets. He wrote about it on my project page (see my signature for more info about his mod).

For those that do not know what the S06S is, it's the 24 USD controller in a size of a cigarette pack.
My 18S Q100H Frankenstein S06S project is here: https://endless-sphere.com/forums/viewto ... =6&t=68305

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Re: 2WD (Two-Wheel Drive) FAQ

Post by Hangdog98 » Dec 30, 2014 7:16 am

drew12345 wrote:Has anyone done SingleTrack with 2wd? I'm wondering how it would handle and would motor overheat with all the stop and go and rolling hills.
I'm using the Keyde motors in 2WD with what appears to be lowish amp delivery. It's no good for single track. On the types of uphill challenge faced on even mild singletrack routes the front spins out and the rear bogs down and overheats. I should have listened to the experts, volt up and gear down they said. It'll be fun they said. They were right.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by drew12345 » Dec 30, 2014 3:13 pm

Thanks for update! I was planning on trying this out next year. Glad you let me know.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by hodgie » Feb 28, 2015 12:30 am

OK, this two-motor idea has me wondering. I may have a need for a very powerful e-bike to pull a small trailer.

I have two Heinzmann brush motors ....one from a 36v orig eBike and one from a 24v orig eBike. I understand both motors are probably the same in design (both could provide at least 500W each at 36v +). Not real fast but quite alot of low end torque, right?

Could I put both motors on the same eBike with the one 36v eBike controller [brush] (which I hear can accept 40+ amps) operating both simultaneously powered by a single battery pack? Any snags? I wonder if there is something about controlling a brushed motor that makes simultaneous twin motor control very difficult.
Own 36V and 24V Ioccoca EVG's with original Heinzemanns. Want to replace auto transport as much as possible. Eventually looking to upgrade 24V EVG to a 48V+ rig with a direct drive motor. Figuring out the battery technology right now to get my 36V EVG usable. BMS is still a bit (a lot) of a mystery.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by dogman dan » Apr 28, 2015 6:45 am

I think it would be possible to run both brushed motors on one controller, however, they'd share the power.

So each motor would run cooler, sharing the power, but you wouldn't have as much power as two controllers with more combined amps.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by medved » Dec 25, 2016 5:25 pm

I'm thinking about 2wd with two Cute Q100 motors and S06S or S12S controllers.
Is it possible to connect two SxxS 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

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Re: 2WD (Two-Wheel Drive) FAQ

Post by amberwolf » Dec 25, 2016 11:00 pm

medved wrote:Is it possible to connect two SxxS controllers in master/slave mode?
No, you would have to do it as others have, sharing these controls between the two normally.

However, the Lebowski controller brain chip can do master/slave, if you want to build your own. A look around will find a number of threads with that name in the title to read about various builds for it, as well as acquiring and updating the brain chip, PCBs to install it on, etc.

There may be others (Adaptto?) that can do it as well, but the "typical" ebike controller cannot.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by medved » Dec 27, 2016 1:42 am

Thank you amberwolf.

I'm afraid that I don't have enough skills to deal with Lebowski brain chip and Adaptto is just overkill for this setup.

I'm thinking now to connect all sensors and S-LCD3 display to the front motor controller. And will split throttle signal to both front and rear.

So I will have 2wd human-electric hybrid on pas and when I push throttle, both motors will roll.
Will it work like I described? And most important, will the rear controller work properly without the LCD display and sensors?

Thanks and Happy NY!

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Re: 2WD (Two-Wheel Drive) FAQ

Post by motomech » Dec 27, 2016 4:22 am

Early SO6S/SLCD-3 combos defaulted to #2 speed range(slow) when "pinned" to run w/out the display. Not sure about the later versions.
I have run 2 like controllers off one throttle signal. Keep the common gnd. short. Even doing that, there was some signal degradation and resultant roughness in motor response. Nothing major, but noticeable.
I was prepared to build a system where the the second motor was run off a C.A. when I rigged two throttles. I liked that enough that I have been running that system for several years now.
There is no reason to run both motors all the time and some advantages to having independent control.
One is the ability to control the frt. motor, which, even on low power systems like the Q100/SO6S, will spin the frt. tire at times. With all time 2WD, some sort of differential might be a good idea.
Another is I can streatch the range slightly by using only one motor.
Here is how I use two throttles;
100_0028.JPG
100_0028.JPG (88.18 KiB) Viewed 724 times
100_0029.JPG
100_0029.JPG (98.78 KiB) Viewed 724 times
It's very natural and intuitive, but I only use both together when a fast start, like crossing a busy intersection.
Most of the time, I run the rear motor w/ the PAS and add the frt. motor w/ the thumb throttle for hills or a top speed run.
Since the frt. motor will not be using PAS, any simple square wave controller will do, but I'm not sure about combining unlike controllers.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, 2.4 Holly Rollers run ghetto tubeless. 25 mph. Mean Well HLG-320H-48A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 12S LiPoly elifebike 9-FET 17A controller. 20 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: 2WD (Two-Wheel Drive) FAQ

Post by medved » Dec 27, 2016 10:06 am

motomech
Thanks for sharing experience!
I will order 2 throttles and try your approach first.
PAS, display, speed sensor and throttle 1 will be connected to the front controller, and throttle 2 to the rear.
So if I'm using PAS mode and want to add rear motor, I just use the throttle 2 and it won't affect assist.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by motomech » Dec 27, 2016 11:01 am

I actually have the PAS on the rear, but I guess it doesn't matter.
Although I didn't realize it when I first built 2WD, the biggest advantage is being able to have a nice pedaling feel of a low-powered system w/out having use expensive components to "tame the throttle". But at the same time, having an ebike that can jump up into a higher performance envelope.
On my mountain bikes, the frt. Q100 is not that noticeable, but I kept adding more and more battery(LiPoly addiction)until it wasn't that great of an assist bike anymore. At that point, I went w/ a bigger rear motor and built another assist bike w/ a single Q100.
I have tried about every combo. of Q100 motors in 2WD and if you have the time, you might want to run your build list, starting w/the donor bike, by me.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, 2.4 Holly Rollers run ghetto tubeless. 25 mph. Mean Well HLG-320H-48A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 12S LiPoly elifebike 9-FET 17A controller. 20 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: 2WD (Two-Wheel Drive) FAQ

Post by cycleops612 » Dec 27, 2016 7:21 pm

An absent important 2WD scenario, is that which dominates the EV car market - the petrol electric hybrid, like Prius only two discrete motors.

An example niche would be a rural long ride to town for school/work or errands & some hills. Use the ungeared small petrol motor to cruise, and electric for torque and quiet/relaxed in town errands. No hassles with cops here in Oz where petrol is illegal.

Engaging regen on DD motors when using petrol power can recharge if desired. No range issues.

if the motors power the same wheel, the regen could charge while stationary, or serve as a mobile electric power generator.

Even simple friction drive petrol is fine since electric is doing the torquey stuff.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by Monkeypowah » Nov 22, 2017 5:21 pm

Hi new member just slightly bumping this thread.
I'm building a 2 geared hub motor bike now, motors are cheap ebay conversion 250W, with 36V 15A controllers, only cost 100 quid each with wheel, tyre and controller, brakes, throttle the lot.
The battery is a 15AH 48V, so overvolting from the start, I'm sure they'll handle it.
This is a EU spec system, but has a link wire to overcome 250W/15MPH restriction, going for simplicity, one throttle feeding the two controllers.
I'm building it firstly into the wifes old Giant hardtail and as an ex Enduro dirt bike rider, I'm looking for something to tear up the trails, speed is irrelevant, the main reason is my entire dirt bike trail system in Wales has been converted to MTB usage, so I'm looking for something of a lightweight motorcycle that will pass as a MTB , obviously my spec is low so far, but hoping to convert to a higher torque fatbike rear hub and 24 inch wheel.
Probably going to go for a simple push button switch to kick in the front hub when I need it on the throttle wire.
I don't really need to ask any questions, I'm just going to finish it and see how it goes, terrain is slippy and rocky so many of the problems here with regards to syncing and efficiency don't really apply, I'm hoping the lightweight low power hub should keep the front end light enough and may even keep the front controller restricted, with a two position switch, one kicking it in and another reducing the power.
I have no idea if this will actually work, but I'll report back as it does or does not happen.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by motomech » Nov 22, 2017 8:35 pm

No big mysteries here, lot's of folks have built 2WD bikes. I've been doing it for 7 years.
I think your first problem is your 15 Amp constant rated batt. W/ two motors, you will need twice that.
You also might want to rethink your throttle araingement. One throttle directly to two controllers often interfear w/ each other and some folks use a buffer like a Cycle Analyst. And a switch is way too course for off road usage, you need a way to modulate the frt. motor.
I use two throttles.
Basicly, I would suggest you search and read some more to see what works and what does not. Humbly, I might recommend searching thru my posts.
Or maybe read thru this thread that you have drudged out of the mists of the past.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, 2.4 Holly Rollers run ghetto tubeless. 25 mph. Mean Well HLG-320H-48A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 12S LiPoly elifebike 9-FET 17A controller. 20 MPH.
https://endless-sphere.com/forums/viewt ... 8#p1237928

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Re: 2WD (Two-Wheel Drive) FAQ

Post by markz » Nov 22, 2017 9:23 pm

You are breaking the law, are you prepared for that? It seems you are, but still lack the cojones to go say 36V 30A into a 21" for ultimate torque at same price as the feeble weakness 250W. I digress, restraint is the key here, just feeling twitchy, never understood weak. Dont mind me, I see this is your first post. Welcome. Your thread would have been better placed in the Electric Bicycle topic, for future reference of course, I dont care either way but you get better responses when you place a well typed post in the correct topic.

Lets get down to bizzzzsnitch, 2 cont 1 throttle, well I remember reading someone hacking up two throttles working on the twist action, where the front would turn on until you got to 1/2 or 3/4 throttle position. Cant believe 250W, yes still twitching over here.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by Rassy » Nov 22, 2017 10:18 pm

As far as running two controllers/motors from one throttle, I've done it several times with no problems, even a couple with three controllers/motors from one throttle. Same technique with both brushed and brushless hub motors. As long as the controlers and motors are the same and in same size wheels and they are both getting their juice from the same (or paralleled) battery packs you should be fine.

There was some speculation that there could be some issues that would cause a problem between the two controllers via the throttle wiring, but I just paralleled all three throttle wires to both controllers. So sure, there may be a risk, but I think the risk is worth it. Two motors on the same rig seem to really enhance their performance during hill climbs.

Of course the comment about battery capacity may be a concern if the battery isn't rated for at least 2C.

Welcome to the forum and good luck with your project(s).
-Rassy-
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https://endless-sphere.com/forums/viewt ... 28&t=69419
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Re: 2WD (Two-Wheel Drive) FAQ

Post by Alan B » Nov 22, 2017 11:56 pm

We have definitely seen interference from controllers with parallel throttles due to the large battery currents causing differential voltages to the throttle inputs, but it does not always happen and it is less of a problem on lower power motors. Do make the controllers close together and join the controller battery ground wires together near the controllers and keep the wires very short and heavy so they share the same ground. Don't connect the throttle ground wires together, connect the throttle to the main controller, ground, +5 and speed as usual, and connect the speed wire only in parallel across to the other controller. Try it and see how well it works. You can use settings in the controller to adjust the front/rear power, and even have the front motor drop out at higher speeds if you wish. Disconnecting the front speed wire with a switch should be fine also to select 2WD on the fly.

If you want to discuss your build plans it would be good to start a thread on your bike, and keep this thread for an FAQ, and report here with summary results and/or problems.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by Monkeypowah » Nov 23, 2017 3:06 am

Thanks for the tips there, of course 250W is mostly just an imaginary EU compliance figure, , I presume these controllers limit the amps to give approx 250W, but in reality they will be running at at least 15 amps, heat dissipation being the issue, the bike needs to look as normal as possible, so small gear hubs that wont be kicking stones in riders faces is what I'm looking for.
If it turns out just switching the controller for the front is too harsh, I'll fit a thumb throttle, though I really want simple, too much going on with pushbikes having gear selectors on both side of the bars.
Battery arrives today...so busy tonight, it is a 2C by the way.

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Re: 2WD (Two-Wheel Drive) FAQ

Post by markz » Nov 23, 2017 4:47 am

In reality it could very well be a 350W motor labelled as a 250W motor, or even a 500W motor labelled as a 250W motor. There is no standard, its just whatever the seller can sell, they dont care. Just slap on a holographic 250W sticker or stamp it into the metal and wash your hands. Hows the Fuzz going to know anything, all they care about is writing you a ticket so they can puff out their chest to their superior in their power stance with their inflated egos and donuts in hand. You want accurate marketing for motor wattage, Justin at ebikes.ca stated it very clearly in electricbikereview's tour of the old Grin Tech premises in V-Town, in the video its quite near the beginning, I'd say 8 minutes in. I bet you wont watch it, interesting non the less.

Yeah just parallel the throttle wires as mentioned, or scroll up and see the custom throttle jobby that I saw scrolling down to find the response to my spicy post. I'll slap it to ya posting.php?mode=reply&f=2&t=33429#pr1251155

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Re: 2WD (Two-Wheel Drive) FAQ

Post by cycleops612 » Nov 23, 2017 6:25 am

markz wrote:
Nov 22, 2017 9:23 pm
You are breaking the law, are you prepared for that?
I bet you'r fun at parties. :)

Just saying, my longyeah axial drive mid motor (24 powered gears) is only visible to the practiced eye (unlike the battery of course). I strongly suspect a second motor would pass notice.

What hasnt been mentioned afaik, is there are advantages to opting for powering each wheel optionally, vs sharing a controller, and it to some extent diminishes the need for full power to both from a single battery, tho I agree, more amps is better for when you do want both at full power(best avoided rangewise anyhoo). This is not the case when traction is the issue.

I also like regen on one (front ideally) but not both motors, due to the slight drag.

In theory, I think I would opt for a twist throttle, with an adjacent thumb throttle, and with practice, both controllable with one hand.

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