New BB drive (retro fit)

[Miles]

That's true. You need a powerful hub motor to go fast and steep

 

[flecc]

question is (for me) just for interest:
which bike (lets say hub-driven) can you use for 30% hills (without burning) ?
is there any ?
and: does the same bike go well at speeds over 30km/h as well ?

None classed as legal in the EU quite will do both, but you can get close. The legal Heinzmann motor comes in geared versions as has just cropped up on qeeeme's thread. The high geared version in a 26" wheel will assist at just over 30 kph but have poor torque. The low geared version has a maximum assist speed of 18.5 kph and has more torque, but it would still struggle on that 31%.

My 25 kilo bike with a 576 watt peak legal eZeebike motor gives me 27 kph and I can just about climb a very short 30% with a struggle, though at your age that would be easier than for me. This bike is a modified eZee Quando with added rider gears, but not a style you would like I think.
.

 

[Miles]

Using 16" wheels would make a big difference, though. Small wheels have greater advantages for electric bikes...

 

[flecc]

Using 16" wheels would make a big difference, though. Small wheels have greater advantages for electric bikes...

Mine are 20" wheels Miles, the motor designed for EU legality in that size, though it exceeds the 25 kph with a freshly charged battery.

I take it you mean a hub motor advantage in small wheels?
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[Miles]

Mine are 20" wheels Miles, the motor designed for EU legality in that size, though it exceeds the 25 kph with a freshly charged battery.

I take it you mean a hub motor advantage in small wheels?
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Hi flecc,

I think kraeuterbutter said something about using a trailer with 16" wheels, in another thread - that's why I brought it up.

Yes, a particular advantage with hub motors but also better for chain drives and direct to hub systems with an external motor. Better for hub gears, too....

For me, 20" wheels are the best compromise.

 

[flecc]

I like the 20" compromise too Miles. I'd forgotten Kraeuterbutter's mention of that trailer wheel size.

Can't say I've ever been convinced about arguments for small wheel size advantage versus gearing change for the same effect though. I can see the opposite on road surfaces in practice. Convince me otherwise.
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[Miles]

There's not much advantage for a non-assist bike (apart from overall size and luggage carrying). Anything that gets the motor spinning faster for the same gear ratio has to be a plus, for us, though....

Using 20" wheels makes it just about feasible to put a motor through a hub gear.

How am I doing...?

 

[flecc]

Not bad.

That's what I meant when I said "I take it you mean hub motors".

Unconvinced on other drives though, the gains being small, especially with chain drive gear reduction, and offset by small wheel losses on less than perfect road surfaces through vertical movement absorption.
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[jimmyengland1000]

Does the BB kit cost 2,000 Euros then? Sure? It can't possibly succeed at that price, can it?

I had a good look at their site and the videos etc. I must say, it reminds me of my electric toothbrush for some reason.

One point someone mentioned is that the pedals rotate when the motor is on. I heard the word 'freewheel' mentioned on the site but I'm not sure what they mean? Wouldn't it be a bit dangerous having the pedals spinning round without a freewheel?? Like the old fixed wheel bikes (you'll have built them, Flecc?... no not the penny farthings... )

 

[Miles]

I was assuming 20" wheels with dual suspension - I should have said that.

I've found that suspension works better with an assist bike, as the sum of the torques is less cyclical. You get less bobbing.....

 

[flecc]

I was assuming 20" wheels with dual suspension, I should have said.

I've found that suspension works better with an assist bike, as the sum of the torques is less cyclical. You get less bobbing.....

I agree.

Not on the fully sprung Quando I though, not available now though. Combination of a powerful high torque motor, crude on/off throttle action, short soft sprung fork action mismatched with long action soft rubber bung rear swingarm suspension. Could outdo a pogo stick any day and Kwells advisable.
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[Miles]

.....................

 

[flecc]

Does the BB kit cost 2,000 Euros then? Sure? It can't possibly succeed at that price, can it?

I had a good look at their site and the videos etc. I must say, it reminds me of my electric toothbrush for some reason.

One point someone mentioned is that the pedals rotate when the motor is on. I heard the word 'freewheel' mentioned on the site but I'm not sure what they mean? Wouldn't it be a bit dangerous having the pedals spinning round without a freewheel?? Like the old fixed wheel bikes (you'll have built them, Flecc?... no not the penny farthings... )

Yes it's very expensive. Love the toothbrush comparison.

Fixed wheel drive is still around though, always used in one type of cycle track racing. You may have seen it, all warily watching each other and cycling at crawling pace until one breaks and there's a mad sprint to the finish line.

Quite a few hardy souls like fixed wheel on the road still, and the parts are readily available.

I wouldn't like a fixed motor engagement though, and I feel sure there's a freewheel in that BB system.
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[kraeuterbutter]

i think its this way:

there is a free-wheel: the freewheel (you can see it on the video) is between the 90°-gearing and the planetary-gearing

so: the 90°-gearing is spinning always when the pedals are turning...
the freewheel is there, so you can pedal yourself when motor is not turning, without YOU turning the motor by pedaling

but when the motor turns, it turns the pedals.. so you can´t stop pedaling and the motor does not pedal..
at least thats how i think it works ?

have read about low-assist-bike and there was said, that when the motor is moving the pedals you learn to spin the pedals much more smooth and "round" than without...

on a road-bike, a trike or something i think this is cool..
on a mountainbike.. hmm..
specially on hard terrain i woul dlike to stop pedaling and stand on the pedals so i don´t fell..
so this would only be possible when the motor is standing

for the bike-trailer: yes, it has 16"...
want to use it with chain-gear (instead of hub-motor) because i want to experiment with some different (small) motors..
i think the biggest problem will become traction... -> 10kg light trailer should push a 100kg bike without free-spinning the little 16"-wheel ?!? hmm..

 

[Miles]

I couldn't resist quoting this literary flight from the Gruber site:

"A touch of the Turbo button at the bar end – and the burning sensation in your thighs disappears – the healthy perspiration, however, remains."

 

[flecc]

Brilliant! . . . . . . . . .

 

[jimmyengland1000]

I couldn't resist quoting this literary flight from the Gruber site:

"A touch of the Turbo button at the bar end – and the burning sensation in your thighs disappears – the healthy perspiration, however, remains."

Presumably, women riders "merely glow"?

 

[simonbarnett]

only if they're ladies- "horses sweat, men perspire but ladies merely glow"- maybe it's a class thing?

 

[jimmyengland1000]

only if they're ladies- "horses sweat, men perspire but ladies merely glow"- maybe it's a class thing?

That's it... the litmus test to find out if your girlfriend is truly classy. 15 minutes on the electric toothbrush bike will tell you. Or us males can try it too... if we don't perspire, we're not real men

 

[simonbarnett]

mine (wife) can't even ride a bike, so I'm not sure about this test?? but anyway where's the battery hidden on this bike?