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Bicycle cheat wheel, how does it work?

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IvarA

Mechanical
Oct 8, 2011
14
You probably have seen in the news that a girl was found to use "mechanical doping" in her bicycle. So I found an article about this . Apparently the the second generation uses a motor embedded in the wheel. Anyone have an idea of how this could work? Where are the batteries for instance?

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For that to work, it would need to interact with the frame in some way. Without translating it, it appears to be similar to a "stepper motor" type of technology, embedded into the wheel. For that to work, it needs to have a magnetic field to interact against. I suppose that could be engineered into the fork, but it seems like a lot of work for 60W of power.


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
 
Hi Jeff

I followed one of the links and it basically shows a dc motor hidden in the frame at the "T" intersection where peddling sprockets are driven and further states that it is powered with batteries in frame work.
I'm not sure what the picture of wheel is supposed to demonstrate.
Chuck
 
The pretty picture is somebody's idea of what a wheel motor could look like. Yes it would need a position sensor and coils in the forks.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
It might only be 60 W of power, but that's like adding about 25% more to the prime mover's continuous power rating ... That's a lot!
 
Yeas, that image of the small geared motor is of the cheat motor mounted inside the vertical tube, driving a gear on the hub.

I think the "motor" above is a different idea: The motor armature is built into the hub of the wheel, the magnets are in the tube(s) and pulling/pushing the rim that way.

My "old" bike generator was only a few watts, and you could definitely feel the drag energizing only two flashlight-sized lamps! Can it work? The geared DC motor? Definitely yes - though for longer distances the bigger the battery.

This one? Maybe.

Be better if they just made it obvious, and did not try to "cheat" - people would buy electric bikes.
 
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