Kids Electric Mini Goes Brushless, Pops Wheelies

[ThatHpiGuy] had a problem. He wasn’t impressed with the performance from his kids’ electric-powered Mini. The 6 volt system was anemic at best, and was just begging for an upgrade. Pulling off the seat and checking the undercarriage, [ThatHpiGuy] realized the motor and gearbox were a perfect fit for the Turnigy 2300 Kv motor from his R/C short course truck. A couple of screws later, car-docuand he had the fastest ride-on toy on the block. Since this was a quick hack, [ThatHpiGuy] kept the truck’s R/C receiver, electronic speed control, and 2 cell LiPo power setup intact. The result is a cooperative system where he controls the throttle via R/C, and his kids control the steering.

That steering is still a bit of an issue though. Like many kid toys, the Mini only has one drive wheel, in this case the right rear. If [ThatHpiGuy] pours on the power a bit too quickly, the single wheel either spins or forces the car into a hard left turn. Aside from that, it looks like both [ThatHpiGuy] and his children are having a ball with this hack. The car will even pop a wheelie from a standing start! You’ve got to see it after the break.

40 thoughts on “Kids Electric Mini Goes Brushless, Pops Wheelies

  1. I wonder if you can fix the driven wheel to the axle and then use it that to drive the other wheel. It probably won’t have the best bearing points on the chassis though.

    I am really surprised he didn’t just turn the gearbox into chips with that motor.

      1. get a grip!!

        THE only reason to have a diff is for corners on SEALED roads, otherwise every corner is a power slide!

        on full size cars we have diffs to stop tyres scrubbing out and “sedate” cornering.

        On dirt if I’m driving a 4WD that has lockable diffs, they stay locked!!!

      2. I think it’s not relevant in the case of a toy car for kids. It doesn’t matter much if one of it’s wheels slip during turning or not, we’re not talking a ton of weight here. No need for a diff.

          1. I have to disappoint, traction control isn’t that easy to implement. Requires a lot more than just an encoder.

            Source: i’m a car enthusiast working in the IT of the company which invented ABS and ESP. One of the old ABS devs explained it all to me when we were bored on our winter testing facility up in Sweden. It’s complicated.

          2. In it’s most basic form yes it is. I worked with high school students and implemented it in 2009 for FIRST robotics. We had plastic wheels on a plastic floor. We used encoders and current sensors and compared the wheel speed of the driven wheel to a coasting wheel. If they were too far out of balance we cut power to the driven wheel. You can also look at the current and if you see it drop sharply then the wheel is spinning.

            Throttle mapping would also be a huge help, to set acceleration curves.

            Stability control is not an option on one wheel drive.

            I mean this was pretty much plug and play, so compared to this mod yes it would be a bit of work.

      1. sure you can.

        a throttle circuit is different than an ESC. I believe Lord Nothing is refering to a simple 555 based PWM / PPM generator circuit which could replace the remote control receiver inside the car so the kids cold control the throttle locally. This signal goes into the ESC and the ESC is what chopps up the DC power from the battery to form the 3 phase square waves for the BLDC motor.

      2. just google 555 servo controller. escs use the same pulse timing as servos do. so all you are really doing is replacing the receiver with the throttle control circuit.

      3. exactly. You are changing the PWM duty cycle for te old 3 pin analog RC servo. A 555 with a couple of diodes and a port plus cap is all you need to generate the signal.
        I designed my ESC from scratch and played with RC in my high school days.

    1. That motor size has been the de facto standard motor size for R/C cars, power screwdrivers, hair dryers, power wheels, and hundreds of other devices for at least the last 30 years. I remember using them in my R/C racing days, over 25 years ago (now I feel old), and we referred to them as “540” size motors.
      I’m not surprised in the least that the new brushless R/C motor fit the power wheels. It’s kinda like the smallblock Chevy V8 of the electric motor world.

    2. I dunno, it makes sense for motor manufacturers to use standard mountings where they can, so the industry can use standard parts, and when you pick a motor you can pick it just based on it’s power or speed. Though to see it in a little plastic toy car is impressive, you’d expect them to cut corners where they can.

  2. Just add another motor on the other rear wheel and thats it. you can even get a cheap remote, disassemble it and put it under your child foot, so he/she can control the speed also.

    Dont forget that it has no breaks..
    And plastic tyres will not last long, but..

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