# Chainless ebike drive



## durask (Nov 16, 2020)

This chainless drive system could revolutionize e-bike designs


No chain, no belt, no worries.




www.theverge.com





Pretty interesting. Essentially you pedal and drive a generator which then powers the engine or, I assume, it's more like you power a generator that produces a certain amount of power which can be used to provide feedback.

My concern is that the generator/feedback hub will be way too complex and heavy. I can see this working on road/city bikes - mountain bikes I am not so sure.


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## 127.0.0.1 (Nov 19, 2013)

do you know how severe the power loss will be ?

the most efficient electric generators on earth come to ~63 percent gross efficiency, and they are massive (efficiency gets better when you scale up)

this tiny thing, is not that. so imagine roughly 50 percent, likely more, of your input power wasted, just to get volts out the back end to power the wheel

standard pedelec e-bike is twice as good as this could ever be

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some of us know how much drag those little light generators put on the wheel to power a feeble bulb...it's gonna feel a lot like that, only far worse


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## rockcrusher (Aug 28, 2003)

this is a pretty hilarious. It is essentially a regenerative braking system in a car where the braking adds some charge to the battery pack so you can increase your range. This converts your bike from being able to travel without battery power to being 100% reliant on battery power. Sure you could sit there and spin at a standstill to add some charge back in but if you had a chain you could just ride the bike. 

The article itself notes that maybe this is good for delivery bikes but I feel like you might gain more back with a regenerative braking design vs. pedal powered generator. At this point with this technology just go with pegs and add the generator to the wheel.


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## _CJ (May 1, 2014)

Regen doesn't seem to work on these little bikes. There's a video of a guy coasting all the way down Pikes Peak on his SurRon, which claims regen, and only gaining like 1% battery life or something.

I think you need some weight behind it for it to work. I've driven cars with regen, and it charges up fast, like right now, when you're going down a mountain pass. You can even see it charge the battery just hitting the brakes for a stop light or whatever.


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## RustyIron (Apr 14, 2008)

Yeah... no. 
250w motor is a dealbreaker, and they don't even mention what this contraption weighs.


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## matt4x4 (Dec 21, 2013)

250 watts isnt many peoples cup of tea.




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Electrom1 Long Wheelbase Recumbent Light Electric Vehicle - Page 3 - Endless Sphere






endless-sphere.com


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