A guide to multi-motor (2WD and 3WD) ebike drive systems
ฝัง
- เผยแพร่เมื่อ 10 ก.พ. 2025
- This will Justin's 2nd live stream video tutorial after the Spezi talk and will focus on the design, optimization, and wiring hookup for ebikes and trikes using more than one motor.
There are many situations where multiple hub motors or the combination of a hub motor and a mid-drive motor can be ideal for ebike propulsion. Most often this is implemented when one alone won't have enough power, but it's also useful for traction purposes to get all-wheel drive, for scenarios where vehicle geometry requires it (e.g. Christiana style cargo trikes with an IGH on the rear), and finally for having the best of both worlds (e.g. mid+hub motor) and built-in redundancy on long distance trips.
However, running dual motors also adds complication to the wiring and controls system and there are many part selections details to consider for seamless operation. We will go over in some detail the various wiring strategies that can be used to effectively run multiple motors from a single throttle or torque/PAS sensor device.
Thank you so much for doing this presentation - hugely informative. Can't wait to view your presentation on "Designing all electric drive trains" (aka human-electric series hybrid setup).
What a fantastic resource. Thanks, Justin. I’ve started woking on modifying a lightweight car trailer I pull with my EV by adding two hub motors. The biggest limitation is finding single side hub motors that can handle the load. Very few hub motors give load ratings.
Glad you found it helpful!
I'm thinking about modifying my Radrunner to run dual battery and dual motor eventually, but biggest idea is designing and building my own 3wd Velo mobile.
47:45 I used to have this kind of a setup with two independent motors and throttles in my bike. It wasn't practical, cost-effective or efficient, but it was sooo much fun to ride when it was snowing. I've never had that much fun on a bike. Hoping to build something like it again sometime. :)
I'm trying to make a setup just like that. thank you
Really glad you made this video! I'm doing a dual direct drive motor mountain bike and was contemplating adding wiring for disabling one hub or the other but seeing your charts about core losses is going to keep the build much simpler! Thanks!
Glad to keep you on the more efficient and simpler path!
thanks for the talk, this is useful in setting up dual motors with a single cycle analyst, in particular the information at 55:54
What a great video to watch I’ve been trying to get my head around it all for ages I watched this and it’s straight forward and makes it a lot easier
Fantastic vid, thanks. Really interested in you doing a deep dive in regenerative braking.
I learned a ton from this video. Thank you very much for making and sharing it.
Spot on love your common sense and ingenuity ! Top stuff and your products are well made ! Keep the info coming ! Thank you for your time and knowledge it has helped me more than once !
Your presentation was excellent...thank you!
Incredible comparison! This answered SO many of my questions! Thank you so much! I plan on being a Grin customer very soon!
Watched & listened to 1st 38m. So far I’ve enjoyed being told what I know already. Then concept of freewheel able geared hub motor!!!! Now my brain is overfull.
thank you , this has everything needed to know clearly .
Puts hand up.
I was one of the Catrike guys that got all excited after seeing the Cat at the bike show last year.
Wow, you explain everything so well, well done, thanks
Interesting points in this topic and well explained. Thanks
My E-CELLS Super Monarch Crown has 2 wheel drive with two BAFANG 750 watt, 52 volt (yep) motors and two 52 volt batteries, front down tube battery is 20 Ah, rear, under rack battery is 15 Ah. Maximum load rating is 400 pounds including rider but not the 95 pound weight of the bike. My single controller is a 52 V sine wave 45 amp with 18 MOFSETS in a sealed conductive gel for cooling which also uses two aluminum fin arrays on the box. The bike uses a torque sensing 9 (NINE!) level pedal assist.
The HQ for E-CELLS is in Pahrump, Nevada, fortunately for me B/C I live only 60 miles away in Las Vegas, NV.
FIELD CHARGING: BLUETTI AC200 MAX Li Fe Po inverter battery charged by an Off Grid TREK 220 watt solar blanket cable locked to the roof racks on my SUV. This system works great and can run a large cooler all day W/O depleting the big LFP battery. My bike has a patented, frame mounted charging port to charge both batteries simultaneously. LOVE this "beast".
Thanks for doing this presentation... I thought I would have to figure out a lot of this stuff with trial and error
Great video and super informative, thank you!
Best free video online today.
As a Dane I got a warm tingly feeling when he mentioned the Christiana bike so casually.
We see them everywhere here, and I was thinking about electrifying one with 2 front motor hubs. However, all the electrical versions are sold with back or midwheel drives.
Better get a mid drive. A BBSHD will do it perfectly
Yeah, you only would need the dual hub motors upfront if you are steep hills to climb with your cargo and a single motor isn't up to the task. It is really impressive what dual hub motors can do, and the benefits of regen on this kind of vehicle are huge which you can't take advantage of if you go the mid-drive route.
Please do the all-electric drivetrain. I've been tinkering with that idea for a while and would love to see you explore it.
Just a great and informative video. I run a fat bike with a rear wheel 500 W 36 volt Bafang motor and an S900 lcd. I added a front hub motor Mxus 500 W 36 volt with an SW900 Display And duel matching batteries. One for each motor. The S900 is the master controller so the pedal assist, brake sensor and throttle signal wires share from the S900’s controller to the SW900’s controller. I get 18 mph full throttle with only the rear hub Bafang running on a level surface and if I add the front hub Mxus. I get 21.5 mph full throttle on a flat surface, but more important is I get enough torque now to climb hills in pedal assist mode and 2nd gear that was previously killing the Bafang motor alone. The Mxus motor only shows 78 watts on the hill climbs. I wish I knew The information in this presentation before hand, but it looks like I’ve made a good guess On my all wheel drive set up. Thanks again a great presentation.
Hey there and thanks for sharing your experience building your own 2WD setup with these 3rd party controller and display products. I'm guessing that both of these are geared hub motors? You'll probably find that switching out to a controller with a torque throttle will help a lot for getting a more balanced power share on the climbs.
Grin Technologies I understand how PWM works with the MOSFET and PAS, Throttle, Brake Sensors etc, But the only torque sensors that I know of are in mid drive motors, Thank You
Great presentation. I really think that a setup with a DD rear and a slightly slower geared front motor would just work perfectly even with a voltage driven controller. In high power situations they would share the load and at low power thr faster DD would done the work entirely without even turning off the geared front hub. I think I'm gonna try this setup.
That will work, but you will have no load losses from the grades motor just spinning within the freewheel you are going fast and not actually contributing. So you will have the core losses of two motors but only the power output of one. If you can set a vehicle speed limit to cut out the controller driving the geared motor once it is not contributing then it will work perfectly.
@@GrinTechnologies Well, The easy way is to use the sigle/dual switch button on the controller (almost all dual escooter controllers have that) it basically switches off one of the hubs/controllers. In a dense city setting it would be on but doing pace it would be easy to switch off or reengage... but then again, it wouldn't be automatic... not perfect :) I might as well stick with the brute force (2xDD)
@@GrinTechnologies I’m about to do this to my RadRunner with the geared motor in the rear and your all axle DD on the front. Is this auto shut off easy to configure on the Phaserunner?
Dual motor is also interesting for people that plan to overvolt their existing motor, but are worried about overheating.
You'll still overheat, you'll just be going faster before it happens.
I came to see a mulit motor, kinda like some kind of power 80s hair cut. Turns out the info on trikes was handy too.
10:30 - I agree, but if the phase wiring on the controller blows out you will have to disconnect it and HOPE it hasnt blown off the actual wiring on the inside, or you would have a motor that is working against you until you swap out the wheel. I think I would rather carry an extra rear wheel and controller or two just in case.
A failure that results in phase wires being shorted inside the motor itself is exceedingly uncommon. It's almost always either blown controller mosfets, or cable damage outside the axle, and in both those cases it can be remedied without having to take the wheel off.
Hi Justin - as an EE major, its nice to see a proper EE approach to this motor efficiency business. Very informative. A question on your simulations - it would appear at 24:59 that both System A and System B benefit from 200W of human input, for a total of 400W in which case it can't be compared with a single motor getting just 200W of human input? I hope that your simulation 'add' function knows how to handle that correctly? Best regards.
Yes for sure. You'll notice if you use the "add" function on the simulator tool that the human watts input for system 'B' is disabled as it is no longer part of the equation.
@@GrinTechnologies Thanks - now I look closer I can see some of the figures are greyed out. Missed that on first viewing!
For low traction applications it would be useful to have a feature so that the front (secondary) motor's speed can not exceed rear motor's speed by more than a certain percentage value. Think about riding up a slippery slope where under equal torque the front would naturally spin out.
Yup, but that requires an additional control circuitry with access to both wheel's speedometer sensors. We don't currently have any hardware to tie in that feature though it is a pretty obvious one to implement if 2WD ebikes were much more popular.
Thank you. Nerd Level - Jedi.
I'm glad I'm back here watching this. I should have just placed it on repeat until I incorporated positive chsnges in my life.
Clean my room dammit!
This is so sick for people in wheelchairs very curious to see how this develops
Very informative about two motor systems. Can you go more in depth on how to setup a three motor system?
Hi Jesse, much of the same principle applies just extrapolated to 3 motors and motor controllers. The wiring is a bit messier but the fundamentals are the same. If there's a specific question about a 3 motor setup you've got that wasn't addressed here we'll be happy to answer in the comments.
I have one of the old Truck Trikes built by Bill Stites. It has a cycle analyst running two ezee controllers with the dual controller shunt. My question or confusion is with the dual battery inputs. I have two 48 volt 23 ah batteries and if these are in parallel wouldn't that put the voltage at 96? I've noticed the batteries are numbered 1 and 2 and the trike will function with only one battery but only in position #1. Also #2's input leads have whatever voltage #1 battery is, standing there at the input.
What would be your suggestion for a full system upgrade that would allow for regen?
I really appreciate all you've done and continue to do!
Fantastic! Must have the CA3 with WP8 shared on my dual motor seutp :)
I use two throttles because I can feather the front motor as a anti slip system to eliminate wheel spin when I start riding the bike.
If you get a controller with a torque based throttle response, then you can simply set the maximum torque on the front wheel motor to be a value low enough that doesn't skid out. Then no feathering is needed.
excellent presentations, thx for sharing. could not find pole voting on your web page, so ... i would vote for how-to-solar-charge-ebike-battery, and some examples of common setups which include regen braking, and regen-braking-shallow-dive - basics, like do i need any extra electronic, what batteries are best to use (perhaps capacitor largo, for big amperage ...). i am making e-powered solar charged trailer, for world touring, and your video presentations gave valuable insight into required equipment. thumbsUp, have fun, s love nia
Great video! Are there options for using large capacitors to get full power regen breaking? We would need controllers with separate regen power output, and a manager to keep capacitors discharged while respecting the battery charging limit.
There is zero need for that, modern lithium batteries can absorb all the regen power just fine by themselves without any capacitor to 'help'
You haven't got around to sharing your all electric drivetrain yet. One advantage you never mentioned is aero. ebike world neglects this in general, but an aptera/velomobile shape can go insanely fast with very few watts. Velomobile/recumbents have bad drive trains due to long chain, and either sags or multiple drag rollers. No drive train would allow for lower base (may be impractical on real roads), but also allow a fared shape where you pedal on your back and see forward through mirrors. Easy to see behind and use side mirrors. Even unfared, this would be an inverted superman position, and ludicrous fast road vehicle. A long enough vehicle can have 2nd person using same pedal system but pedalling in reverse if it is circular generator. Vehicle doubles as a sleeping camper! :P
Oh ! And I want to be able to unplug 1 and the controller will still work .& when you have all 3 motors running can you add 3 or 4 batteries ?
Very interesting and informative. I'm in the planning stage of an extended tricycle with the rear axle converted to have a fully working differential and I'm planning to have a dual drive with a front hub and a mid drive, how would I deal with the signal wire in that situation?
I would recommend having it so that at modest power levels only the front hub motor is operating, and then above a certain throttle level (say like 2.5-3V) then the mid-drive motor kick in. Or just run separate throttles for each. Assuming it's a direct drive front wheel then you really mostly just want to use the mid-drive going up hills, but have the hub motor running all the time (hills and flats)
if you are running 2 DD motors... do the 2 of then have to regen of just only 1 ...thank you ....ii enjoyed your presentation ...ii understand what to do now in finishiing my project
You can do regen with just one or with both. The best efficiency and strongest effect will be to use both motors equally for regen just as your do for power
Great video!!! Thanks for the Knowldege :-)
Will left and right wheel fitted with 2 motors act the same as having a Differential?
Yes, there is zero need for a differential. It's fine if one motor spins faster than the other while cornering.
Thank You!
We should meet on live screen share. You'll like what I show you.
Nice!
Oh yeah 😎. OMG 😲 ? White Sidewalls on a Trike? Ha Ha! lol 😆 Too cool 😎 👌 👍 😄
Great video! I'd like to know if there is any issue with switching to dual motor whilst in motion or even whilst accelerating for a dual motor scooter?
Nope, but as mentioned in the video if you have dual motors you should generally be running both of them equally all the time, rather than switching back and forth between 1 motor and 2 motors.
Can I buy a dual motor drive installation kit with console to turn one of them off when not needed and pair a pedal assist with them a separate throttle for the gear drive on a DIY bike?
Hello I just came across your channel and was ver impressed, I am very new to battery powered vehicles but am very interested in it and the possibilities that are available for it. For instance I am a handyman that works around a lake community that is very hilly. I am very interested in building myself a 4 wheel drive cart that could help get material up and down the hills to the lake to work on docks, I am hoping to be able to carry up to 1000 pounds so I am doing my research to figure out what motors, controllers and batteries would work best for this situation. So when I came across your channel I was l very happy, thank you for making this easier to understand, I know I have allot to learn so if you have any suggestions for me it would be much appreciated.
Want to know if therre is a motor controller that can run 3 wheel scootor motors ?
Can you get anymore information on that chair you have in the picture, the beach one
Please
I have really enjoyed watching all of the information you have provided here on YT and your site, they are great to watch and I am amazed that you answered most of my questions/thoughts in your videos before I had the option to ask them! I do have to ask your advice on something though. I am 6'8" (203 cm) 235 lbs (107 kg) and I live in San Francisco which has some REALLY steep hills, the steepest of which aren't officially documented, but the steepest segment is 41%. We have at least 10 hills above 30%.
I am on the waitlist to get a Quattrovelo+, and in order to be able to use it in San Francisco I believe I will require electric assistance, and even then it will have to be robust because I previously had an ELF with a TDCM midrive that would stall out on the hills to my house and I would literally have to get out and push while holding the throttle, even then it was so difficult that I would sometimes slip and have to hang on to the brakes. With the QV I feel that I basically have two options: I can have them install a BBSHD bracket and run a mid drive setup, or run two front hub motors. If I use hub motors I can keep my current drive setup, which is a 75t chainring with a Schlumpf Mountain Drive, so effectively 75/30 chainrings, and 11-46t cogs. If I get the mid drive I have to get rid of the Mountain Drive 2.5 reduction gear and the largest chainring I can find for the BBSHD is 52t, limiting my capability on both climbs and speed without assistance.
I used the motor analyzer tool on your site to compare the options not only at 30%, but also at 0% grade, both with a total load of 150 kg, and human assistance at 250 watts. I used the cda and rolling resistance of a Quest as that was the closest performing velomobile I could find info for, and chose 48v batteries.
I like the idea of DD and being able to reclaim the energy from going down those hills and saving the wear on the brakes, but I don't like the idea of them limiting my speed due to drag. Using the analyzer it seems like the max speed is about 34 mph on flat ground regardless of human input. Would virtual freewheeling eliminate drag at high speeds? I was using Grin v2 FST +Stratorade as the DD drives. Would they be able to contribute at high speeds, when I am out of the city on rural roads, or do they basically have a limit of around 35 mph on 20" wheels?
If I were to use geared hub motors I could power up hills, and they can freewheel when I am cruising at high speeds, but using the eZee 250 RPM motors they would overheat in 8 minutes, faster than the 9 minutes of the DD motors, and there is no reclaiming of energy with regen. On the flats they wouldn't offer any assistance after acceleration as I would be easily going faster than they can spin.
Now if I were to use a mid drive (I used the Grin V2 SLW without Stratorade as the mid drive with a 2:1 reduction, I don't know haw accurate that is compared to BBSHD) I would be able to climb up hills in my 52t/46t gears, and get better range than the other setups and be less likely to overheat, albeit at a slower pace. On the flats I could go up to 42.6 mph under throttle, but I would not be able to contribute anything as I can not pedal >150 RPM. If something were to happen to the battery or motor I would have to push up hills and my max speed would be limited due to the limited gearing. Also, of course, there is no regen.
So, given all of the information, what do you think would be the best solution? Would the possible future addition of solar panels have an impact on what you believe is the best choice?
Thank you so much for your time and consideration, sorry for the wall of text.
Hey there and thanks for the well researched question! Normally this is a conversation best carried over email, but we'd normally say that if the dual direct drive hub motor can do the job and is in your budget, you'll be forever grateful for all the benefits (silence, simplicity, robustness, redundency, and regen) compared to the other options. But the single BBSHD will be cheaper overall for sure. There is no 34mph speed limit, you can always go faster either with a higher voltage battery pack or with the field weakening feature in the controller.
@@GrinTechnologies Thank you very much!
@@GrinTechnologies You've very kind (?) to help out the dude whose claim to fame is shaming homeless people.
Great video! What to you recommend for a tank type steering for a electric dual motor skid steer (low speed)? I'd imagine you would need mechanical braking for turning.
I'm thinking of tank steering for my 3-wheeled, 3-wheel-drive Carla-like cargo trailer.I wonder if I could get some 'tank' steering benefits by using an active voltage amp/attenuator inserted between the CA3 computer and the motor controllers, taking input from stress-sensors in the trailer tow-arm, to modulate the relative throttle (torque/power?) signal going from a split CA3 signal to my two rear-wheel controllers? Somewhere in the Carla Cargo videos/literature they talk about inherent tip-over vulnerability of trikes and I'm thinking there may be a relatively intuitive sensor/voltage control that would tend to stabilize the 3-wheeled trailer during downhill braking+turning, or through any high-speed cornering (the two situations where I imagine tip-over might be most likely). Differential throttling of the two rear wheels could also apply exponentially as dual stress-sensors on the trailer tow-arm indicate the trailer may be jack-knifing and/or over-running the pilot bicycle/vehicle, to both straighten out the trailer and brake it overall (though braking isn't option with the free-wheelable gear-motor rear wheel / direct-drive front wheel configuration I'm now leaning into...). I'm thinking to load my trailer with 1500-2000 lbs payload, so controls and fail-safes to prevent it crushing the pilot and/or bystanders are a top concern - both when it is under proper motor control and when power/control fail for any reason.
Why would you need mechanical braking? An electric motor can brake itself, or even turn backwards, instantly.
Thanks for a very informative video. I'm seriously considering installing 4x1500w hub motors on a quad. This is because I commute up a steep long road to my place (on top of a mountain). What would be the best way to set everything up so that I can choose front or rear wheel drive when not climbing?
I'm guessing I need 4 controllers and I would say two computers screens? Geared sound like an option?
I'm very interested in how hub motors can be installed in this manner, the fact that they're only held by one side of the axle, are they modified or special orders?
Also is there a way around having to run one in reverse? I don't want steering issues with that much power.
I also have the question: how to run more than 2 motors using the CA3 and the Y splitters you feature in vid. Do you just split twice (or thrice or n times) and always use the red-flagged lead on the end-most Y branch? Is there some minimum RShunt value the CA3 can accurately interpret? How do you calculate RShunt for a multi-Y-split controller throttle signal?
@@inklipMedia Probably best to email them.
I cant unhear it now. You use "um" as punctuation in a sentence. You also use it to denote a capital letter/beginning of sentence and its SO CONSISTENT 😄
Very informative video too
It's a delivery detail we've be working on, this presentation is a few years old now.
@@GrinTechnologies no criticism here, just something I noticed 😁
Btw, you guys make the BEST torque arms. I converted my shitty mongoose status 2.2 into an ebike and it kept breaking. One day the entire dropout broke off. I didn't bust my ass because it was still hanging on by the TorqArmV4, which single-armedly held that side of the wheel on and allowed me to ride back home safely. Buying more soon for my new ebike ASAP!
@@GrinTechnologies if theres something I can recommend for your future versions, its to make the hole's width slightly adjustable. I had to shave down a strip of metal with my dremel to make it just the perfect thickness to shove into the hole between the torqarm and the axle, to make it tight so that there wouldnt be that tiny amount of rotational slack. Perhaps you can make a threaded hole going through the side with a screw that would screw in and push against the side of the axle to keep it perfectly tight, as that half a degree of rotation can still allow for some damage to the dropout
@@GrinTechnologies If I can recommend an improvement for future models, make a threaded hole on the side with a screw that would push against the part of the axle that goes through the torque arm hole, to make it perfectly tight and prevent any and all rotation of the axle. That half a degree of slack can still allow for some damage to the dropout. I shaved down a strip of metal and mashed it in, but making it adjustable would be a much easier way. Perhaps even 2 screws, so that the threads suffer less stress. Just make sure the hole is compensated for somehow so it doesnt become a point of failure
Your presentation is fine. What a creeper criticism.
are bafang planetary gears the same as the ones in a rattan 500w hub motor
For slower speed operations for folks with disabilities where traction is needed… any recommendations on lower Kv for this niche?
Usually about 7rpm/v is the slowest wind for an ebike motor. You can always set the speed limit in the controller for lower speed operation. This does not specifically require a low KV motor.
@@GrinTechnologies thank you! I had seen custom wound motors advertised with Kv of 4.5-6 but running everything in your simulator wasn’t sure of what Gain vs your Grin Slow Fat all axle (7Kv) or even an SX1 for dual motor mobility trike. Max 15mph.
Great videos and tools!
Can you set up all axles of my wild one by Stein to fat trike 26 by4.0 rear and 20by4.0 in front.
You didn't go into 3+ motor hookups much. Could I power a 2 (or 3) DD powered wheel trailer from a dual motor bike, with just more splitters? Can I still disconnect the trailer without much fiddling with the Cycle Analyst settings much?
im gonna build my next bike w-2hub motors .
Is it fair to say heat issues only become an issue when motor power to total vehicle mass ratio in excess of 500w/100kg?
Nope, that should not be the takeaway at all. The correct answer is that heat is an issue when the phase current required to sustain the necessary torque for moving the vehicle at a given load point (mostly dictated by %grade & total vehicle weight) generates more heat through copper losses than the particular motor is able to either absorb (through thermal mass) or dissipate (through conduction to ambient air) in the time duration of interest. ex you can move 1000 kg on flat ground at 20 kph using just 500 watts of power no problem, motor doesn't even get warm:
ebikes.ca/tools/simulator.html?motor=M3540&batt=B3623_GA&wheel=20i&mass=1000&hp=0&cont=C25&autothrot=true&throt=72.5
Same output power, but with a much lighter (200 kg) vehicle climbing a 10% grade cooks the motor in just 5 minutes:
ebikes.ca/tools/simulator.html?motor=M3540&batt=B3623_GA&wheel=20i&mass=200&hp=0&cont=C35&autothrot=false&throt=100&grade=10
I have a 26" fat tire ebike with a rear hub. I'm specifically interested in modding it with a front hub for better maneuverability in the snow. My commute doesn't have many hills but we do get pretty rough snow here in central PA. What type of configuration would you suggest? Is it more ideal to place an additional 750w in the front or a smaller 500w? I see a lot of people placing larger motors in the back.
If you haven't made a decision yet, I'd go big power direct drive front hub. We'll presume the rear hub is geared and can get you up the hill. The direct drive can let you recharge on descents. It won't have much torque at low wheel speeds so I think it will help in slow snow situations. Just not sure how to integrate the 2. The rear hub gets you going and keeps you going at slower speeds and at some speed the front hub motor will become more efficient as there is no gearing loss. I like the pluses of regen (what controller is needed?), low torque when assisting, maximum efficiency faster on the flats, especially with an extra 100+ watts of you. The rear gear hub will free wheel.
In 2WD and 3WD setups using hub motors, does the brake trip sensor apply regen braking to each hub equally as well?
If each motor controller is configured to respond to the regen brake signal in the same way, then yes. Otherwise no.
@@GrinTechnologies thanks
Hi, I built a dual-motor setup. I bought all the parts from you guys. You mentioned in this video that there is a trick for making a step function in the phaserunner controller, but you could bot share it because of a glitch. Can you share that info with me?
Best to ask that via email, youtube comments isn't really the right platform for technical support
hello, I was wondering how to hook up 2 mid-drive motors to the same axle, with the motors going at the same speed?
I was wanting to run 2 controllers with 1 48v battery for each controller.
I'm wanting to make a e-bike/mini bike with 2 mid drive motors to the rear wheel.
Yes in principle you can do that just fine as long as you can sort out the mechanical linkage. Electronically it's fairly starightforward. Whether your bicycle chain and cogs will like the loads of dual motors is a totally different issue. I'd expect a very high rate of drivetrain wear and failure. The combination of a mid motor and a hub motor makes much more sense, especially as it gives you regen.
I'm considering a dual-motor system so this presentation was extremely helpful, Thank you! Is there a link to the simulator?
Also, generic question about direct-drive hub motors: should I assume that if I have the DD motor in an off condition that when I am pedaling I will have to overcome the resistive force of the DD motor as described when the DD motor is slower than the flywheeled motor?
Anyone tried to fit a trike 3x3.. I've got a gear less hub motor rear 1500w and wanted to fit 2x500w front. Will this system work?
Yes, but the electrical hookup is a bit cumbersome. The trike in the thumbnail of this video is a 3 hub motor drive.
what i miss regarding this topic is, in case of 2 e-wheels, in parallel, like on trailer, should one use 1 battery, or 2 separate batteries, for each motor 1 battery, and how to reverse direction of 1 e-wheel, if 2 e-wheels are mounted in parallel (ie on trailer, 1 e-wheel is mirrored).
The best in general is to have all the batteries paralleled or one large battery, but it's fine to have separate packs for each controller if that's more convenient, which may well be the case for a trailer assist.
Motor reversing is done with the controller.
I would like to build a fat bike with front and rear hub drives and then maybe add a middrive someday down the road.
I would like to use your all axle aluminum hubs with laced rims, please show us how it’s done what kind of controllers we need what kind of part numbers we need
Hi Larry, best to send an email to info@ebikes.ca with a picture of the bike you've got. Our front All Axle hub can work with 150 x 15mm thru axle fatbike forks. For the rear motor, it would be a geared bafang G060 or G062
2 hub motor with one throttle two controller any technical issue will come? for operation
See the video, I go over this in some detail, but the short anwser is that there are not that many technical issues as long as you have either matching KV motors or are using controllers with a torque based throttle.
@@GrinTechnologies we are using torque based throttle,
@@GrinTechnologies thanks for ur reply
Should buy a full suspension fat trike that will get three wheel drive. A big rear engine, plus your grin all axle motor on the front wheels. You showed very well how two hub engines work together even though they are different sizes, and how to connect the controls and throttle. Wish you showed how to connect three motors. Can you put a splitter on a splitter to control three motors?
Yes sorry for not addressing this more explicitly. All of the same principles apply to 3WD as 2WD, and usually with a 3WD system but then there is 1 more slit to do in the wiring. We're unlikely to make a "3-1" system splitter as a stock cable adapter, but you could apply the same principles to make your own. The splitter on a splitter can work in some cases (like just the simple throttle splitter), but it wouldn't work for the 2:1 WP8 splitter since that has resistors in it for balancing the current sense. I would normally suggest using the dual controller CA3 shunt and then just tapping in a 3rd throttle output wire.
Would another valid reason to "easily" enhance a stock utility/cargo bike with geared hub (radrunner) or mid drive underpowered but torquy motor with a DD hub motor that provides free/powerful braking through regen, and the power needed when utility/cargo capacity is actually used? For radrunner, adding a 1000w front hub motor would seem to be good power/torque combo compared to trying to find a 2000w rear hub DD replacement, which may still be a net torque loss. Though there is probably a mid drive motor that fits radrunner with even higher torque, and adding a rear 1000w dd hub, could provide marginal gains for what is fairly significant extra expense compared to keeping working geared rear hub motor.
Hey Grin Tech, I’m a little lost as how to program my second motor. Listened to this video a couple times...I have a phaserunner and a 40a grinfeon controller I have to divide the ohms...but otherwise with cycle analyst and other than autotuning the phaserunner (which is the second controller and motor) I’m not sure what else I need.
Best to send us an email. I'm presuming you are using the dual controller CA shunt? In that case you just set the CA to 1.000 mOhm, and have the throttle output of the shunt go to the throttle inputs of each controller.
Hi. I watched this video to find a solution for riding in the snow. The throttle mapping should keep my rear tire from spinning at takeoff if I set the rear motor to engage slightly later than the front. But I don't understand torque-based controllers or throttles. I have a Kelly KLS-S 4812S. It does have throttle mapping and I understand it. I've read the description and owner's manual for my controller but I haven't found anything that mentions torque-based or voltage-based. There are 3 different throttle parameters, but nothing I recognize as torque-based. A little help?
Unfortunately we don't deal with Kelly controllers so cannot offer any direct insight into their settings. Torque is the same as phase current, so if the throttle is mapped to your phase amps then that is effectively torque control.
@@GrinTechnologies ty
@@GrinTechnologies If you could direct me to information on this subject I would appreciate it. I've done searches and haven't found anything helpful.
Excelente
The eZee motor is going up a 2% grade, but the secondary hub has 0% grade. Was that to load eZee more (1hr. 6 min)?
When the two systems are added as they are here, there is only one %grade control since they are on the same vehicle. The secondary %grade slider is disabled and not functional, the value that it has is irrelevant.
Justin, what hub drives exactly did you use on your friend Michael’s Easy Racer conversion for his Dempster Highway trip? I’m looking to set up a RANS Stratus LE with either dual hub drive or front hub and mid drive, depending on how screwed up the rear dropouts come. Also, you didn’t mention another good reason for dual drive: more equal tire wear!
He went with the eZee geared hub motors. But normally for long distance trips we recommend direct drive hubs like the Grin All Axle or FH212 / RH212 series just because there is less that can to wrong with them.
** When your new FREEGEN motors are available WILL THEY WORK AS 2 regenerative braking MOTORS ON MY FRONT AND REAR WHEELS??
i.e. Will your controller handle both for balanced regen and balanced braking?
As long as each freegen controller system was independent then yes, the controller loop is between the brake, the controller, and the motor. But we really recommend that your 2nd motor not be freegen but either a regular geared or direct drive hub motor so you have one totally mechanical back up brake.
What is best two hub motor system it the two tires will be next to each other off road use
I dunno what you mean by "system", but as long as you can mount them, you'd just use two motors and controllers of your choice with a single throttle (and Justin's magic cable) controlling both. Don't worry about turning; the motors will do "differential action" all by themselves. HTH.
Supercaps as regen dump for e-juice when braking?) Where are small clutch-less geared hub motors? Yes, please keep working on the E-zee version.. hopefully front and rear matched pairs..)
good stuff
What about the extra mass of the 2nd motor? Surely that has to have an impact on efficiency but I didn't hear you mention it.
4kg of extra mass has virtually no effect on efficiency or wh/km consumption rates. There would be a little but more energy used going uphill and accelerating, which would be countered by a little more regenerative energy recaptured going downhill or stopping.
What about ABS system for dual regen braking? Or if even, electronically assisted ABS disc braking?
You just don't need ABS with regen. That's a holdover idea from mechanical brakes in automotive systems.
Oh, and one more question: does the phaserunner do voltage regulation? Can I connect a 72V battery to the phaserunner for control of a 48V motor? My hope is yes, the phaserunner does voltage regulation, but I suspect the answer is "no" that ai'll need a DC-DC converter or risk overvolting the motor(s)
All motor controllers do voltage regulation. That is entirely the primary function of a motor controller, to reduce the voltage of the battery to a lower voltage for the motor (and converting DC to 3ph AC of in the case of a brushless motor). Keep in mind that there is no such thing as a "48V" motor. Motors do not have an intrinsic voltage rating.
I'm very new to ebikes. If you have 10 seconds I have a quick question sir; if someone was running 2 hub motors and their combined max current from the controllers was 60 amps, and you used a battery with 50amp BMS (52v 20ah), what would happen? If you ran WOT you may trip the BMS of the battery and it come back on after a few seconds? Or something worse? Thank you!
Nothing bad. Either it will trip the BMS circuit, or it won't. And if it does, either it will turn itself on again automatically, or more likely you will have to unplug and replug the battery to the controller as most BMS circuits latch their over current cutoff protection to the detection of an external load. You have to fully remove all loads from the battery for the BMS to reset.
What height person is this recommended for?
Is there a video or information on the trike with 3 motors?
I've got a trike. If you find out.let me know
I want to know how much service Grim offers when one purchases a kit? Can Grim set the parameters on my system remotely? Is there a way to share CA data with Grim in order to dial the system in according to the data that is collected over a period of riding?
We provide guidance on installation and settings, but can't set your parameters remotely... You could absolutely share your CA data for advice on settings.
What about having one motor with no throtle and the other motor throttle only on seperate system pedalling only on flat then both throttle and pedallin on hills
That works just fine too. In that case, we would recommend that the throttle controlled motor used just on the hills is a geared motor that freewheels.
what setup would you recommend for someone wanting to pull around 450 lbs not counting the batteries and motor weight... im wanting to build a bike that can pull my weight... a 75lb dog in a trailer and camping gear down the westcoast... so steap hills and mountains.. i need long range.. good speed.. and i also intend to mount a solar panel to charge it when i cant find a place to plug up
You know who has the answer? The front desk clerk at Dinty's Motel in Biggs, OR. Good luck, rich boy. ;-)
How about using the iMortor3 motor in front and using a rear hub motor at the same time? Will this work?
Yes, been there done that.
@350:00 what is a good regenerative braking brushless motor controller that is not too expensive? I am going to ask on endless sphere too...
Came here for information on rear differentials for a dual motor set up on a trike, but was told I don't need it, and to ignore the inefficiencies and uncomfortable turns... Efficiency is important to me and because I make deliveries, so is my ability to maneuver, including taking some tight turns. :/
With a torque based controller like the Phaserunner/Baserunner, then is actually no reduction in efficiency and no effect on the steering or handling. Both the inside and outside motors will be generating the same torque even if they are rotating at different RPMs. It's already intrinsically acting just like a mechanical differential.
@@GrinTechnologies Oh no... I'm at the drawing board again. lol Learn some more and like a cascade, you have to change a chain of things. lol Thank you.
Hi.
I have ebike model MATE-X-750W.
Battery 48 V/14Ah fail.
On side battery voltage terminal 42V -when turn battery key to ignition position-drop to 0V.
What can i do?
Buy new one?Where? Replace insert? Where to buy?
The shop or vendor who sold you the bike should offer all the support and warranty. 42V is dead flat for a 48V nominal pack, so naturally your BMS discharge port is tripped. I would start off by charging your battery until it reads 53-54V.
can i do a 2 battery blender with one controler port that will feed two 48 volt motors via a 3 way y spliter on my trike. some one told me that will blow up my electrical system. who is right?
You can run your controllers off a common battery bus or off individual batteries, both options are just fine. But no matter what, each motor needs its own controller.
All same motors and controllers. 2 for bike and 2 for trailer. Question Hou to use one throttle?????
Simply split that throttle signal to all 4 of your motor controllers.
How do you know if your throttle is torque based?
I am planing to build an ebike with two hubs (front and back ) and two mid motors
So what's your opinion
I think two mid-motors is silly and will exceed what you can push through a bicycle chain for no real benefit to speak of over just one mid-motor.
Could this potentially be used for a 4 wheel drive system? Just split the wire again? Would a single cycle analyst be able to do 4 motors?
That's what I want to do. I want to get a recumbent quad and have a hub drive on each wheel. My guess is I need 4 controllers & screens (one for front & one for back) as well as plenty of battery power. Have you done anything like this yet?
@@davidcarr2649 not yet but GrinTech did give some good info. You would need 1 cycle analyst, 4 controllers, 4 hub motors, and enough battery. It would be a bit pricey. Make sure you order the grin tech controllers that allows for a reverse switch.
@@mattmccoy2621 thanks.
did you bicycle across the Canada/USA border? What was your experience like doing that?
Several times, and the experience has always been just fine.
@@GrinTechnologies which border crossing did u use (Huntingdon or Whiterock or?) ? it seems like things have gotten much more difficult particularily when going from Canada to US at thr vancouver . if u use the White Rock crossing is there a path for bicycles to use or do you have to cross with the cars? I am also wondering when u have your trike or quad bicycle with a bike trailer.