DIY inquiry from those with homebuilt e-bikes

m@Robertson

Well-Known Member
Region
USA
Well if we are talking relatively flat ground, urban riding and the need to accelerate quickly, I built the exact bike for that recipe. Have thousands of miles on it.

1. Geared hub.
2. A second geared hub
3. Big battery in the triangle to run them both.

Pedal assist is active on both wheels. Bike accelerates fast enough to make you giggle. In fact I have turned its capability in that regard way down because twin 35a controllers can be a safety hazard unless you slow-start the front wheel, and I was concerned with the frame's survivability long term on the rear so I dialed that one back too. With distributed traction you still take off plenty quick.

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I did a detailed writeup on the thinking behind the 2wd config, but having literally thousands of miles and years riding bikes like this, I can say this is exactly what you want for what you are describing. Note BTW the big front chainring and the little rear cluster. This bike is specific to flat city streets. Also note: ***no suspension***. Not safe on the front with a powerful motor. Want to go skinny instead because people tell you fat is not phat?

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Been there. Done that. Abandoned it. The combination of 30-34 mph and potholes makes more bicycle-y tires a terrible idea.


Also this was gen3... Here's gen 1 from March 2017.
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And gen2. August 2018.

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If you want almost maintenance-free speed and long term durability (two motors barely get warm when working together) on a flat urban commute where you need to be able to accelerate into traffic ... this is your platform.

No mid drive, or even a mid-drive+hub 2wd - can match the acceleration this kind of bike is capable of without going all stupid and creating a 3kw+ direct drive motorcycle suited only for throttle.