Author Topic: Interesting and Unusual Bikes You've Seen  (Read 382512 times)

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Interesting and Unusual Bikes You've Seen
« Reply #2750 on: January 28, 2019, 06:27:45 pm »
Looks as if it's based around an oversize pair of handcuffs!
The earth is vast and beautiful and contains many miraculous places. (Chekhov)

Re: Interesting and Unusual Bikes You've Seen
« Reply #2751 on: January 28, 2019, 06:36:58 pm »
It has to be, given the general impracticality of putting a mechanical drivetrain in there.  Other issues left as an exercise for the reader, but the whole thing comes across as one of those design student creations which has escaped into the real worldhttps://neofold.com/

File under not-road-legal vehicles that have wheels and are faster than walking.

My bold.
This. Very much so.
£956.13?
I don't think so.

Re: Interesting and Unusual Bikes You've Seen
« Reply #2752 on: January 29, 2019, 12:41:56 pm »
It has to be, given the general impracticality of putting a mechanical drivetrain in there.  Other issues left as an exercise for the reader, but the whole thing comes across as one of those design student creations which has escaped into the real worldhttps://neofold.com/

File under not-road-legal vehicles that have wheels and are faster than walking.

My bold.
This. Very much so.
£956.13?
I don't think so.

Well, exactly. You could buy a folding e-bike for that, which would have more uses.
Quote from: Kim
^ This woman knows what she's talking about.

Re: Interesting and Unusual Bikes You've Seen
« Reply #2753 on: January 29, 2019, 03:48:38 pm »
How many attempts have there been at all-electric drivetrains? Folding utility bikes might be one application where they just might make sense, especially if you can add a small battery for e-assist.

Kim

  • 2nd in the world
Re: Interesting and Unusual Bikes You've Seen
« Reply #2754 on: January 29, 2019, 04:11:46 pm »
How many attempts have there been at all-electric drivetrains? Folding utility bikes might be one application where they just might make sense, especially if you can add a small battery for e-assist.

The efficiency gets you if you rely on human power alone, but as you say, that's not such a problem if it's an e-assist bike anyway.  It's something that would be interesting to play with, as you effectively get a software-defined CVT.  And no exposed oily bits.

I suspect the compelling argument against it is that you can make it even more mechanically simple by swapping the genset at the cranks for a simple sensor and adding a bit more battery capacity instead.
To ride the Windcheetah, first, you must embrace the cantilever...

Re: Interesting and Unusual Bikes You've Seen
« Reply #2755 on: January 29, 2019, 06:17:06 pm »
 
The efficiency gets you if you rely on human power alone, but as you say, that's not such a problem if it's an e-assist bike anyway.  It's something that would be interesting to play with, as you effectively get a software-defined CVT.  And no exposed oily bits.

How big are the losses likely to be - 10% overall? In which case it might still make sense (FCVO) for a utility bike in places with civilised infrastructure, especially if the lack of chain means you can design a cunning fold or what have you.

Quote
I suspect the compelling argument against it is that you can make it even more mechanically simple by swapping the genset at the cranks for a simple sensor and adding a bit more battery capacity instead.

Which makes me wonder in a rules-lawyery kind of way: is a vehicle with a 250W motor and cranks that aren't connected to anything but a pedal sensor, a road-legal bicycle?

Re: Interesting and Unusual Bikes You've Seen
« Reply #2756 on: January 29, 2019, 06:26:26 pm »
I test rode a Mando Footloose that tried this a few years ago. The basic problem is that spinning a generator that has no feel to it in relation to your riding is really unpleasant. It also had very little resistance to the pedals so you probably weren't contributing much power.

Kim

  • 2nd in the world
Re: Interesting and Unusual Bikes You've Seen
« Reply #2757 on: January 29, 2019, 07:30:13 pm »
Which makes me wonder in a rules-lawyery kind of way: is a vehicle with a 250W motor and cranks that aren't connected to anything but a pedal sensor, a road-legal bicycle?

AIUI the pedals have to be capable of 'propelling' the cycle, so probably not.
To ride the Windcheetah, first, you must embrace the cantilever...

JennyB

  • Old enough to know better
Re: Interesting and Unusual Bikes You've Seen
« Reply #2758 on: January 30, 2019, 02:35:23 pm »
How many attempts have there been at all-electric drivetrains? Folding utility bikes might be one application where they just might make sense, especially if you can add a small battery for e-assist.

The efficiency gets you if you rely on human power alone, but as you say, that's not such a problem if it's an e-assist bike anyway.  It's something that would be interesting to play with, as you effectively get a software-defined CVT.  And no exposed oily bits.

I suspect the compelling argument against it is that you can make it even more mechanically simple by swapping the genset at the cranks for a simple sensor and adding a bit more battery capacity instead.

One possiblity for a heavy cargobike that has to stop a lot is a hub motor for regen and a low single-speed for maximum human assistance on starts and steep climbs where the motor is least efficient. Once up to minimum speed the pedals freewheel an power a genartor, giving a constant regen of say 100 watts.
Jennifer - walker of hills