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Powerwheels upgrade. 6v to 18v


Red Skull Member
May 19, 2020
Member Number
Milwaukee, WI
​Our UPS man is awesome and helps us out a bunch. I repaid the favor a few weekends ago helping him swap in some Milwaukee 18V batteries into his kids power wheels. Going from 6v to 18v was too much for his youngest, and he wants to slow it down a touch. I tried a 12v, but that was still too fast. Does anyone know what kind of potentiometer would work best for this application?
Some of the slow/fast power wheels did it by switching the motors series/parallel, so in low speed it would put half voltage to each, in high speed it would put full voltage to each. Is this a single motor or dual motor power wheels? The interesting side effect is, low speed acts sort of like an open diff, and high speed, sort of like a spool, in those.

If you want to do it with a resistor (I don't think you'll find a potentiometer that big without spending more than a power wheels on it) ideally you want to know how many amps it's pulling, do you have an amp meter that can measure it?
Nothing useful to add except once I put a motorcycle battery and wrapped inner tubes around the rear wheels of my sons quad he crashed a lot, but it hauled the mail.
My buddy put a 24V aircraft battery in one for his daughter. He had to put screws in the rear tires so it wouldn't just spin them the entire time, then screws in the front tires so she could almost steer it.

The gears in the rear end gave up shortly after. :lmao:

No advice other than don't do that.
Train? Or electric car? Can the battery be tapped in the middle so 9/18 volts?

model trains are all powered with a variac, essentially.
electric cars are all brushless ac motors controlled with thousands of dollars of electrics.

You can't tap the balance ports of a lithium pack for power.

the solution here is to put an 8V battery in it for $20.
I got some pre wired speed limiters from a place called electric scooter parts . Com they may have a plug and play deal you adjust with a philips. Worked ok but once you drop below 50% its a little jerky
Kid just needs to get used to all that pair!!!!!!

wife found this on the side of the road...

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i had a similar problem on a small power wheel car thing. was 6v put in 18v and the sob instantly looped... too much. put in the 12v still scared the crap out of my kid.

then i put a small wheelie bar on it and the kids wore the tires off it. now were onto the bigger ones at 18v and i'm actually replacing tires on them:smokin:
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