Thrift Store Razor Scooter Gets More Kick

Beyond pride, the biggest issue keeping adults off small motorized scooters is the fact that their tiny motors usually don’t have the power to move anything heavier than your average eighth grader. That didn’t stop [The_Didlyest] from snapping up this $7 thrift store find, but it did mean the hot pink scooter would need to be beefed up if it had any hope of moving 170 lbs of hacker.

Logically, the first step was fitting a more capable motor. [The_Didlyest] used an electric wheelchair motor which had a similar enough diameter that mounting it was fairly straightforward. The original sprocket and chain are still used, as are the mounting holes in the frame (though they had to be tapped to a larger size). That said, the new motor is considerably longer than its predecessor so some frame metal had to be cut away. This left the scooter without a kickstand and with a few inches of motor hanging out of its left side, but it’s all in the name of progress.

Naturally the upgraded motor needed similarly upgraded batteries to power it, so [The_Didlyest] put together a custom pack using eighteen 18650 cells spot welded together for a total output of 25V. Coupled with a 60A battery management system (BMS), the final 6S 3P configured pack is a very professional little unit, though the liberal application of duct tape keeps it from getting too full of itself.

Unfortunately the original motor controller consisted of nothing but relays, and didn’t allow adjusting speed. So that needed to go as well. In its place is a homebrew speed controller made with three parallel MOSFETs and an Arduino to read the analog value from the throttle and convert that into a PWM signal.

[The_Didlyest] says the rear tire is now in need of an upgrade to transmit all this new power to the road, and some gearing might be in order, but otherwise the scooter rebuild was a complete success. Capable of mastering hills and with a top speed of about 10 MPH, the performance is certainly better than the stock hardware.

Of course this is far from the first time we’ve seen somebody put a little extra pepper on a scooter. Some of them even end up being street-legal rides.