Does this make sense? (no chain or belt, pedal operated generator and wires to the rear hub motor)

[ZeroEm]

They are selling them over in the EU with a 250w legal limit. 250w generator would be good for me. Controlling a3000w hub would be good. Would only want the generator to provided some resistance so it would not feel completely weird. Would not try to power the hub with it. Just dump the what little you make into the battery. If I could power a 3000w generator then would not bother with it.

 

[ebike4healthandfitness]

https://www.cyclinganalytics.com/blog/2018/06/how-does-your-cycling-power-output-compare

(If you scroll to near the bottom there is a graph showing how watts varies with time for various levels of cyclists. Turns out that even the 50th percentile of cyclists could break 1000 watts if the time being measured is brief enough.)

 

[ZeroEm]

Yes, agree we can put out a lot of power for a brief time. That is why I pedal start after that like to run 75w - 300w so a 250w resistance would be great for me. Was doing 4hr rides so the low wattage is more appealing for that duration. Let the motor put out 3-400 watts.

by ebike4healthandfitness » Oct 31 2021 6:27pm

(If you scroll to near the bottom there is a graph showing how watts varies with time for various levels of cyclists. Turns out that even the 50th percentile of cyclists could break 1000 watts if the time being measured is brief enough.)

 

[BalorNG]

Personally, I want a tadpole with non-steered front wheels, rear steering for slow speds and front torque vectoring for high speeds. Good luck implementing that with a mechanical transmission Yea, this is possible, but I think efficiency drop in oodles of universal joints might in fact exceed that of electric transmission.
Not sure that would with be worth it, but worth a *try* if you ask me...

 

[onemorejoltwarden]

The advantage is in freeing up the designer to be unconstrained, and to clean up the design for folding.

If you have tried to pedal uphill or across an intersection , you know you need 400w burst
and this is a 200w ebike.

 

[helno]

I've actually ridden a bike that used this technology.

It is a side by side tandem bike that would have had a very complex drive to combine the output of both riders. The twin (or more) generator units allow each rider to pedal at different cadences and loads. This layout makes the vehicle very accessible for people who cold not ride a conventional bike (mobility issues etc.) You can actually add on additional trailers with additional generator units.

http://www.geminusbikes.com/

It is a very special case but it is only possible using a pedal operated generator.

I got to test ride the generator units at various stages of development and it went from very strange to pedal to feeling very natural. Pedaling while stationary feels a bit strange.

 

[Chalo]

http://www.geminusbikes.com/

It is a very special case but it is only possible using a pedal operated generator.

That's not true. Sociable tandem trikes have been around for generations. You can even build one from purchasable plans:

These nothing a motor-generator drive does better except make power while stationary, and waste more pedal power as heat.

 

[mxlemming]

A good use case for this would be to put stabilisers on it so you could keep pedaling at traffic lights and have a higher exercise time per ride. Apart from that, it's horse shit.

 

[ZeroEm]

At least we have something to talk about. Remember when autos came out, they would never replace the horse. Want to see a waste of power and heat. Take a good look at Automobiles. Clearly people don't really have an issue with wasting a few watts.

 

[helno]

That's not true. Sociable tandem trikes have been around for generations.

You seem to have missed the part where I talked about accessibility for people who would struggle to even get onboard a conventional bike with a chain.

This layout allows the seats to rotate into position with nothing in the way of the riders feet. For someone who has severe mobility issues this enables them to board a bicycle without needing to lift over the drive train. They simply sit down on the seat put on the seat belt and then rotate into position and lift their feet onto the pedals.

In this use case the lost efficiency is less important than what the form factor enables. For a regular bike yeah I agree it's a waste of time and energy, but then again why are we talking about this on a website dedicated to adding additional energy consumers to an already very efficient vehicle?

 

[fechter]

But efficiency wasn’t the team’s main goal, and they consider the slight efficiency drop to be worth the tradeoff, which is the increased design freedom that should open the door to countless opportunities for interesting electric bicycle construction.

If you want to go faster than standard gearing will allow yet still get some exercise, I could see this sort of working.