Taking the DIY E-Bike Off-Road (and into the water)

There have been a few questions about this ~300w ebike and the places it can go.  I try to address some of those through experimentation in this video.

Among the tests done, I go over a few speed bumps, jump the curb, zip through some uneven grass, displace some sand, and hit the waves. All on two wheels.

The industrial outdoor grit/grip tape on the skateboard drive wheel helps keep traction in wet conditions, like rain. Without it, the two wheels might break traction and wear out the tire.

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This bike has a locking lever on its front fork tube. Normally, it gives the rider a more efficient ride when riding on pavement or asphalt by preventing energy from being absorbed in the suspension with every crank of the peddles.

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Since the motor clamps to the inner suspension tube with a couple U-bolts, the suspension must remain locked, as is the case with this bike. Otherwise a large series of jolts on the front wheel may disengage it from the motor’s drive wheel.

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Towards the end of the video (6:21 – end) there is also a brief overview of the electronics.

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I also discovered that the controller will take 34 volts from an 8s LiPo pack. This makes the whole thing loads more fun with the added acceleration and extra 3 to 5mph boost.

It also seems like the controller actively regulates max current to the motor, preventing damage to it or the motor.

More info on how to build the DIY e-bike can be found here:
http://thestuffwebuild.com/projects/diy-electric-motorized-bicycle/

8 thoughts on “Taking the DIY E-Bike Off-Road (and into the water)”

  1. Hi,

    How old is the motor? How long do the scooter motors last? How much do you and the bike weigh? Around how fast were you going in your video?

    I’m working on my own ebike with a friction drive system very similar to yours. I’m trying to figure out if I should get a 250W motor or to upgrade to a 350W or 500W motor. Thanks!

    1. I’ve had this motor for nearly a decade, maybe more. All it required was a simple noisy bearing change a few years ago. As for the weight, the electronics (motor, controller, wires, etc) add about 8 or 9lbs without the batteries, which themselves vary by preference. I’m not sure what my, or the bike’s weight are. Speed averaged around 20mph on the normal land, and maybe 9-14mph on sand. This motor is listed as a 24volt, 280w motor; I probably wouldn’t go any lower than that.

      1. Thanks so much for the response!

        Do you think a motor controller is absolutely necessary? I saw a guy connect the motor, switch, and battery all in series and just hit the switch to turn the motor on. Do you think that will damage the motor a considerable amount?

        1. The controller often works to limit current to the motor and increase safety overall. While a series-switch-motor-battery will work for a short while, some serous pitting will happen on the switch’s contacts, potentially fusing them shut. Large current spikes that occur before the motor is up to speed might also damage the motor, batteries, or even wiring harness.

  2. Hey bro!Its myself from India😎.I gonna make a project inspired by yours.as this is India im not having the Razor 300 motor.so,tell me a replacement.

    Batteries:I am having 2.5 AH 12V motorcycle battery

    http://www.amazon.in/COSMOS-MOTORCYCLE-MAINTENANCE-BATTERY-2-5AH/dp/B015R20942?tag=googinhydr18418-21&tag=googinkenshoo-21&ascsubtag=78ddb567-e802-4412-92aa-5fdba69d02ba

    will that help me in any instance??or else ill buy the LIpo batteries online

    Controller:Is that necessary??
    Thanks!

    1. I don’t know of any scooter part distributors in your area besides international sites like eBay, sorry. Two of those batteries (in series for a 24v motor) you linked could work, though not for very long compared to a 10Ah SLA battery pack. You will also need a speed controller, especially if using LiPos since most controllers will protect themselves from short circuits and overheating.

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