I just took this science experiment for another blast this morning. God dam its fast. It definitely accelerates harder than even motors.
Until such time as I man up and do some damn science on this beast it will have to reside in the pile.
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Nice! I’ll be running a dual diagonal setup(if I can fix my first vesc) with different motors. Rear will be Enertions big rspec and front will be a Tacon 160. It will be fun for sure!
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@lowGuido This is so cool! I’ll mention something obvious, but not yet noted; this approach might allow dual-rear configs with more motor can options. Maybe you could use different motor can sizes, one large one (63mm) and one smaller one (50mm) without running out of room on your trucks!
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Nice @sk8ace a UDD setup as it would be… interesting to hear how that goes for you.
@treenutter yes the can size is something that has crossed my mine once or twice before.
Ok, so here’s my question - what if you put a brushed DC motor on one truck and a BLDC on the other? Brushed motors have maximum torque at zero RPM, which would give you great take-off power and then as the power on the brushed motor diminishes with increased RPM the BLDC kicks in and pulls you the rest of the way.
Also you wouldn’t have any of the issues with over RPM drag since the brushed is not a “timed” motor.
I might have to try this.
DougM
don’t BLDC also have max torque at 0 RPM?
Yes that is correct:
Theoretically, but in reality I have to kick the board to get it going - otherwise it stutters a lot, whereas a brushed motor could give you clean smooth power off the line.
One problem with brushed motors is that the bigger they get the lower the rated RPM, so getting a powerful enough DC that matches RPM range of the BLDC would be tricky.
DougM
Been reading this thread with intrigue, especially as I have a spare motor and ESC laying around. So it sounds like this setup worked quite well considering the weird configuration. I’m happy with the explanation given, but my only question is this:- Would the slower motor create a braking effect as it tries to turn slower?
No it wont slow down. If you use VESC with current control, the motor always try to spin at maximum rpm all the time. If one motor has higher rpm than the other, the drag effect will occur (not braking).
Ideally uneven drive is similar case to car engine differential if I look at it. If there is less load on one side of the wheels, that wheels will spin faster taking all the current and power (normal differential and not slip differential). What it comes to eboard is that the motor and the batteries will self balance the power distribution.
It works exactly the same on a regualr dual drive with the same motors. With two ESCs each driving thier own motor, each one will always try to do its best individually.
I’m not 100% sure how the traction control option in VESC affects this when using dual with the CAN bus. I can’t really tell the difference with it enabled or not enabled honestly.
Here is my plan/theory. Use a Tacon 245kv and SK3 260kv motor with slightly different gearing; 17/36 & 16/36, respectively, since I have both of these motors and could fit them both on one truck. Theoretically, I’m expecting it to run similar to a normal dual drive, but I’m not sure if there would be any issues with running this setup.
Has anyone else tried this type of even uneven setup or have any opinions or comments?
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I don’t see any reasons why this wont work. what ESC’s are you planning on using?
I would be interested in the results… especially with different gearing.
I encourage this kind of thinking. outside of the box, not just what everyone else tells them to do.
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I wonder if you could fit a Tacon 160 and Tacon 110 in a dual rear configuration, then you’d have an uneven drive and disguised as a regular old dr drive. Lol
well the 2 SK3’s that I used in my original setup are so very similar in size that you hardly notice the difference. however you can feel it.
I’m going with torqueboards 6s to start.
This is awesome. Ya’ll know what would be sweet mash up of unique ideas? Carvon skates dual drive from a single motor (pictured) x2 using the Stacked KV motor idea in this thread. Credit to carvon for the drive set up, I just like pictures.
Lol who needs to stop?
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not 100% sure whats the point of this. 
if you run dual motors anyway, will you really ever need the extra torque of one low kv motor? or would you ever need some mixed topspeed of 2 different kv motors when you could just tailor kv to your max desired speed and go with that? I ran dual rear 63mm with max speed 50kph+ and more torque was the very last thing I needed on that setup.
in my eyes, you just add an uneven load that will add extra wear on belts and wheels, will add extra load on motors leading to extra loud bldc noise and you probably loose efficiency too. ontop of that, while accelerating from stand still to max kph, the torque will smoothly swap sides on your truck, so youll constantly have to readjust your weight. probably no biggie, but might add some confusion and possible instability.
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If everyone walked straight in a line no one would dance.
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