Found this dual shaft board, any idea what the motor might be? Unfortunately the original thread on ES seems to be gone, I PM’d the builder but haven’t had a reply.
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The builder got back to me, said the board would turn OK off road but was difficult on pavement, probably because of the large tires. I’m toying with an idea using Bellville washers as an overload clutch to allow some slippage and speed differentiation in high traction situations.
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Did a thing, kinda works. But when turning, imagine the esk8 being like a drift car, one wheel is in constant tokyo drift mode
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Are the aluminum discs just spacers or do they provide some slippage?
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One of the disks is used to mount the second shaft the other holds a bearing
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That explains why I couldn’t see a dual shaft motor on their website. Clever idea to make your own that way. Which motor did you use, does it have plenty of power? Is the shaft a press fit into the motor end disc?
Is there any axle support on the secondary side? I would think it would probably be fine if there wasn’t, but I don’t see much of a point of the second mount if there is no stabilization.
EDIT: I now see that the second spacer is mounted to the motor mount. I just got a bit confused when I saw the pic with the titanium bolts
I came up with one possible solution to low traction wheel slip since I haven’t been able to find a dual shaft motor. I made a “limited slip differential” for the board so I could have the 2 front motors turning together when taking off in low traction situations. Seems to be working pretty well off road so far, I even get a bit of slip when carving on pavement, I put some strips of tape on the coupler and the motors to see if they ever rotate independently and they do to some degree. It’s a 1.5 inch flexible pipe coupler that was able to stretch around the slightly more than 2 inch diameter of the motors with some work. The only down side is I have to remove a motor to get it on and off, though I could slit it and use zip ties or hose clamps, which would allow some adjustment of pressure and slippage.
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I did find after riding about 5 miles on pavement that the rubber sleeve started to migrate to one side so I need to put zip ties or something on the motors to prevent slippage. Just had a thought that I could adjust the amount of slip by biasing the rubber sleeve more to one motor which would provide greater grip on that motor while reducing contact and grip on the other to allow more slip. Or slide it completely off of one motor for road use.
Turns out that was a custom modification of a Hobbywing 70125 inrunner that Moe Stooge did.
Tried another version using 2 rubber pipe caps with springs underneath them to keep them pressed together. Probably could have gone with stiffer springs but this does work. The downside is the rubber on rubber interface doesn’t release smoothly, it grabs until it doesn’t and then slips. I think the concept is good I just need something other than rubber mating surfaces to allow more progressive slippage.
What motor is this? @JaysTCB Looks like a Castle Creations or X-Team but I don’t see any dual shaft motors on their sites Motors for Surface Products
1/5 - X-TEAM BRUSHLESS DC MOTOR
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Motor shaft sorcery… or he’s a machinist 
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This motor is a castle. I modified it.
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I also made some dual shaft Rocket motors. 
Funny thing… this diy build is from The beginning of 2022.
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How difficult is it to press the shaft out of an inrunner rotor and press in a new one? Did you have to heat it up?
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Each motor is a little different. But not horrible. Takes a few hours
I can see a dual shaft motor used on commercial boards.
Dual shaft motor could be very useful on mountainboards. You would basically have a locked differential, much like 4x4 vehicles have.
I recently rode uphill on some ice/snow on my 4wd board. One wheel would sometimes start to spin wildly and dig in. I would love to see how that same ride feels with a front and rear locked axle. Perhaps vesc traction control would provide more or less the same benefit, and some of the same drawbacks. I’m not sure.
Let’s develop a 4wd limited slip differential for esk8. That’s clearly what we need.
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That’s essentially what I’ve done with the rubber couplers and caps above. I have some ideas for a slip clutch type diff that would work on a dual shaft inrunner as well.
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