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possibly a stupid question...

Posted: Wed Mar 11, 2009 10:44 am
by Delinquent
Is there anything in the regulations that state how the drive is taken from the pedals to the wheel on an assisted bike?

Say for example you removed the chain and all it's associated gubbins and had a generator attached to the pedals, then a motor on the other end - would that pass scrutiny?!

Posted: Wed Mar 11, 2009 1:57 pm
by MB
No it wouldn't. Forgive me, I can't remember the exact wording, but in effect the regulations state that is must be possible to cycle the bicycle without electrical assistance.

This means the bike has to have a mechanical drive from the pedals to the wheels.

The mechanical drive also has to be 'usable' - so you can't away with pedals the size of matchboxes and unsuitable gearing.

Posted: Wed Mar 11, 2009 3:34 pm
by Delinquent
bum, that's that idea up the spout then :lol:

Thanks for the clarification though.

Posted: Thu Mar 12, 2009 8:28 am
by qdos
Not sure hat your idea was but you'd also have to pedal like mad just to crawl along.

Posted: Thu Mar 12, 2009 10:24 am
by Delinquent
qdos wrote:Not sure hat your idea was but you'd also have to pedal like mad just to crawl along.


not if the gearing between pedal and generator were appropriate - it would afterall just be a much less efficient way of transferring your energy to the drive wheel. (I say much less efficient - what's the efficiency of chain drives running through a diff? could be just slightly less efficient rather than much less)

It was however mostly a question to see if the pedalling side of things could be semi-sidestepped whilst not completely removing the useful input of a bit of physio.

Posted: Fri Mar 13, 2009 8:56 am
by qdos
Well that' would be good as you'd get more energy out than you put in..... ;)

What you're really looking for though in all seriousness is this
http://www.optibike.com/

Ridden one, very nice, very expensive but yes they work and are pretty amazing but I'd save my money personally

Posted: Fri Mar 13, 2009 10:06 am
by Delinquent
qdos wrote:Well that' would be good as you'd get more energy out than you put in..... ;)

What you're really looking for though in all seriousness is this
http://www.optibike.com/

Ridden one, very nice, very expensive but yes they work and are pretty amazing but I'd save my money personally


eh? lost me there, may be having a thick moment. Just increase the pedalling effort is all.

Now those optibike - the OB1 they say they have sold out of... at a price of $13,995 :shock: :shock: :shock: :shock:

That's just over £10k of today's money, for a bike. I'm in the wrong business... unless they are just in the business of bovine excrement. Even the most basic one is $5k?! My brothers titanium bike he had hand made for the TdF barely cost that much.

I was trying to avoid a physical link between the wheel and pedal (other than cables) which the opti still has though.

Posted: Fri Mar 13, 2009 3:14 pm
by Jeremy
There's nothing in the electrically assisted pedal cycle regulations about needing any mechanical connection between the pedals and the wheels. All they say is that the max assisted speed must be limited, the motor cannot deliver more than the power limit and the bike must be able to be pedalled.

A system where the pedals drive a generator which then drives an electric motor is legal, as long as the pedals can drive the wheels without assistance from the battery (even inefficiently). Such a system would allow a trike to be pedalled all the time, even when going downhill or when stationary, for the purposes of charging the battery.

Mind you, sitting at a junction, pedalling like mad to top up the battery, might look a bit odd!

Jeremy

Posted: Fri Mar 13, 2009 3:26 pm
by Delinquent
Jeremy wrote:There's nothing in the electrically assisted pedal cycle regulations about needing any mechanical connection between the pedals and the wheels. All they say is that the max assisted speed must be limited, the motor cannot deliver more than the power limit and the bike must be able to be pedalled.

A system where the pedals drive a generator which then drives an electric motor is legal, as long as the pedals can drive the wheels without assistance from the battery (even inefficiently). Such a system would allow a trike to be pedalled all the time, even when going downhill or when stationary, for the purposes of charging the battery.

Mind you, sitting at a junction, pedalling like mad to top up the battery, might look a bit odd!

Jeremy


that's the important bit! Thanks Jeremy, very interesting, I'll have to investigate this properly then.

Going to have a look into the efficiencies of chain drives and gears as well as someone just told me they are really very inefficient when used on trikes?