A Hybrid Powabyke?

[Rod Fuller]

Tongue in cheek, but it might be a practical proposition. A small ic engine driving a generator to charge a battery. As the driving mechanism is the electrical motor, then it is still a pedelec, not a motor assisted bicycle.
Did any one see Top Gear Clarkson on a rocket/turbine propelled bike, he estimated 73mph!

 

[flecc]

It's been done but is still illegal since it cannot be shown what power the bike is using, battery or direct from the generator. There's also a restriction on manufacturing on the public highway, electricity in this case. Here's a twin motor example, a Panasonic unit crank drive Lafree with an added front hub Heinzmann motor and a generator on the carrier:

 

[Rod Fuller]

It's been done but is still illegal since it cannot be shown what power the bike is using, battery or direct from the generator. There's also a restriction on manufacturing on the public highway, electricity in this case. Here's a twin motor example, a Panasonic unit crank drive Lafree with an added front hub Heinzmann motor and a generator on the carrier:

View attachment 10617

Interesting, a powerful bike, neat generator, but presumably in excess of 250W

 

[jonathan75]

I think it's using the power just to charge the battery, but (I'm going to go out on a limb here because I know nothing) in any case I gather it's the controller and/or motor which determine the power draw on a generator, rather than the generator actually pushing the electricity at the motor if that makes sense. One thing I've learnt from reading this site is that the wattage limit, interestingly, just refers to a figure printed on the motor which actually represents the *minimum* continuous wattage it will put out. The real max wattage running through a motor, is apparently the controller amps x the battery voltage, so a "max 250w" motor could it seems do 1000w and still be legal. I think.

How that works I don't know and I'd be happy if anyone were to clarify or correct this - because (to go off topic, apologies) if it's true it's not clear to me why a 350w or 500w motor with 250w printed on it isn't legal provided the bike has the speed restricted to 15.5 mph (given the wattage issue seems so meaningless).

 

[D8ve]

The old test for motor power was could it produce X watts continually?
It was to confirm a minimum power output.
This gives a continus power rating not maximum as it was assumed the motor would be rated at max level. Ie my car can do 150 mph etc.
The manufacturers realised that they could rate virtually any motor downwards to spec. Hence same motor can be rated at 250 of 500 watts.
The cap is then speed limiting and power usage.
End result is 250 watt motors some running near 1kw max power but all rated legal with cut out but a genuine 200 watt motor without speed restriction is classed as motorcycle but with much less power than some legal pedelecs.
If the OEM labled it 250 watts and its speed limited then how can you an unsuspecting customer be riding anything but a legal bike! That's what the CE mark is for.
If you home build in exactly the same way, then you are a speed freak attempting to corrupt the morals of society. Guilty etc.

 

[flecc]

Interesting, a powerful bike, neat generator, but presumably in excess of 250W

The Panasonic unit is 250 watts and has it's integrated battery, that Heinzman front hub motor 200 watts. I guess they could only run at the same time if the generator fed the Heinzmann directly since that Panasonic 24 volt 6.5 Ah NiMh battery couldn't begin to power both motors. I don't know what switching arrangements it had though.
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