Is it possible to fabricate a differential for esk8, thus allowing for less motors but still getting 4WD?

I’m apologize to whomever made these, but I recall a guy on the forum who made gear drives that placed the motors facing perpendicular to the wheel axle. This got me thinking about the possibility of using one motor with axles coming from both sides to power a set of wheels, but this can’t work of course if you try and turn the board… So I’ve been doing some pretty extensive research about how they work, and I have a concept that would basically allow for a deck to have 2WD with a single motor, or 4WD with two motors. Actually, if you got the right powered motor with the shaft coming out both sides, you could have 4WD with just one motor actually… Anyone have some thoughts on this?

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This was talked about in another thread I believe it was the weird theories and ideas thread but not sure

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This Has been talked about a few dozen times. It’s always just that tho. Talk.

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Fair enough, lol. Was just curious. If this might now be possible given all the advances we’ve made and how many members are making complicated gear drives with their own CNC, I just though this might be less of a pipe dream now haha.

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I’m not saying I wouldn’t love to see it.
It’s just always an idea without a plan.

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It would be likely far more expensive than just getting 4 racerstar 5065 motors.

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I’ve talked with a German dude working on a diy Bajaboard S2. His plan was to make a spur gear differential. Straight cut gears make a differential somewhat easy to manufacture compared to many bevel gears. A Bajaboard actually has room for such sillyness unlike a longboard.

Possibly in the mountain board size category

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2WD with a single motor has already been done. That could be doubled for 4WD with two motors.

4WD with a single motor sounds extremely complicated. I imagine the mechanical parts would add more to both board weight and cost than an extra motor+VESC.

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The cleanest AWD is with hub motors/DD.

Instant monster.

I do like mini gear drives on each wheel too don’t get me wrong :joy:

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Come on now. Links? Pictures?
I saw a 3d printed one a year or so ago but never any updates on reliability or performance.

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Two motors is better than one motor and a differential. Cars use a differential because they can’t fit two internal combustion engines in there among other reasons.

Cars that are electric use a motor per wheel.

It’s just better that way. You could just use smaller motors per wheel if space or weight is an issue, and get better performance than from a bigger shared motor.

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Diff are used on air filled soft rubber tires urathabe and much lighter weight board and rider has a lot less friction and will alow it to skid around the corner on powered wheels. Look at go carts much wider wheelbase softer wheels works fine for them

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Useing a extended axle saves on motor and ESC but still gain more traction for acceleration and braking with only a little less Manoeuvrability.

In my opinion brakes are the weakes point of a single motor build and the weak point is the 1 wheel contact patch why iv upgraded to dule motor on all my boards.

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Agree 100%

But better than no tail :smirk:

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What about this one?

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My current build uses a single 80100 to drive both rear wheels without any differential whatsoever. It works totally fine, it does turn well, although obviously not as well as with two motors.
@janpom linked my build thread above.

That is not true, Teslas and almost every serious electric car have one motor per axle (or only one in the front or rear if not 4wd) and a single speed gearbox.

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Letting go of practicality can be hard sometimes.

I only say Taycan, with two motors and a two speed gearbox

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You all raise great points. I was just recalling @sofu build where she uses motors that are perpendicular to the axis. Was just thinking something like a 80100 with extended axles from both ends could power the whole thing. If one motor is to much stress to death with, then a couple… I dunno, 6390s might work for 4wd, or other similar motors that are very high powered.

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Ok, you’re right. But two speed gearboxes are pretty new (came with the taycan) and only used to achieve even crazier acceleration. And the taycan also has one motor per axle.

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I am still undecided if I would really recommend the “single motor - 2WD” approach to someone. I really don’t have any problems with it so far and it handles absolutely fine (for me). And it is somewhat less complex (one motor, one esc, only need longer shaft and a bearing on the other side).
But you also need a very beefy and expensive ESC. A single VESC 6 is not enough imho. In a dual drive setup it can handle half of the system current fine, but being limited to 80A total system current is not great.
I just did it because I had the components (especially the single ESC) anyway. And luckily it turned out pretty great.

Edit. What I am trying to say is that if you are starting fresh the best thing to do is probably go dual drive as everyone is doing it and it is more or less plug and play.

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