Radical new electric bike drive system requires no chains or belts

if this can be made lo-tech, without any software and hi-tech gadgetry, then it's a killer.. even if 10-20% less efficient. Most people don't need racing.. It won't need any gears and switching them anymore, as electrical motors have mostly same torque on whole range ; The force of pushing pedals does not need to match the uphill - as long there's something in battery ; And one can keep pushing downhill regardless of speed, and that energy will not be wasted..

If that 5% figure is correct then this is pretty amazing.<p>Do you automatically get regen if you&#x27;re going downhill? Some ebikes require backwards pedalling to trigger that.<p>I&#x27;d been looking at belt drives which apparently aren&#x27;t as efficient as a well lubed clean chain, but may perform better than a neglected chain.

Racers pedal at around 90rpm, commuters pedal around 60rpm. Small generators are not efficient until 5000rpm or so, so this will need a two or three stage planetary gear to increase the rpm by about 100x. Each stage loses around 3%, so that&#x27;s at least 6% gone before we even get to the electrical losses. I think this system will end up only being 80-85% efficient pedals to wheel.<p>On a manual bike you really notice a 5% efficiency change, like after you clean and oil your chain. On a electric bike I doubt you would notice.

Basically this is the same thing as commonly used for diesel electric trains and diesel electric submarines, but replace the Diesel engine with your pedaling.<p>Not a terrible idea, but significantly less efficient than a chain. I’m not sure if I like the idea or not, honestly; I’d have to ride one myself. I’ve currently got a Shimano Steps cargo bike and enjoy it, but that’s a traditional electric assist. With the complete decoupling that would feel odd, at least at first.

&gt; The motor isn’t particularly powerful at just 250W, though that’s the EU limit for electric bicycle motors in Germany.<p>That’s really quite low given that this is the total output including input from the rider.<p>Also, this type of bike will not operate at all if the electronics malfunction. As the proud owner of an ebike that regularly glitches and can neither assist nor shift (!) when glitchy, losing power entirely would be even more annoying.

&gt; A Schaeffler representative explained to Electrek that the Free Drive is approximately 5% less efficient than chain drives.<p>Isn&#x27;t this just describing battery to motor-on-wheel efficiency vs. battery to motor to chain to wheel efficiency - for when you&#x27;re <i>not</i> pedalling?<p>What about the loss incurred on the pedal-generator and electric power transmission side, for when you <i>are</i> pedalling?

They could use this for an all wheel drive mountain bike.

Didn&#x27;t get how it&#x27;s moving the wheel without chain