O.T. Tandems and how you pedal them

[Murmansk]

A friend of mine has taken up tandem riding with people with learning diffi culties. She goes on the front and one of them goes on the back.

I had never really thought about it, but was surprised to learn that the pe dals on the back go round in time with those on the front ? so if the pas senger doesn?t want to pedal and just rests their feet on the pedals, the y?ll actually impede the pedalling action of the person on the front, who will end up pedalling a heavy machine with two people AND be fighting agai nst the passenger!

Is this the only design of tandem or do some have one design that allows th e passenger to ?rest? without impeding progress!?

[Ron Lowe]

That's pretty much how they work.

There are different chain configurations, but in general, there is a 'timing' chain linking the front and rear cranks.

The person at the back is not the 'passenger', they are the 'stoker', with all that implies!

The person in front is the 'captain', but in terms of who gives the orders, 'The stoker is always right!'.

[Artic]

Murmansk scribbled...

Explains why Tim Booke-Taylor used to be thinner.

[Tim+]

You would need a freewheeling chainwheel/crank to achieve this. Such things do exist and it would be possible to build a tandem that would allow the stoker to freewheel whilst the pilot continues to pedal.

That said, I think even someone with learning difficulty would get the hang of a conventional tandem fairly quickly but I've no experience so I could be wrong.

Tim

[Gazz]

Yup, a freewheel chainwheel for the rear (or even both) sets of pedals is what you want, i'm looking into putting a crank drive electric motor on my bike, so have been reading up about these things recently, in my application the freewheel chainwheel is to allow the motor to power the rear wheel without driving the pedals round, another freewheel unit is on the motor's output shaft, so you are not turning the motor whilst pedaling home with a flat battery :)

you will need to ensure you can keep the chain line if you only fit one of these, as the freewheel unit results in the pedals being a little more spaced out (the ones for electric motor applications are usually spaced out a bit more to clear the motor if it's mounted on the bottom bracket)

I've read that the freewheel chainwheel idea for the crank drive motors was taken from tandems, maybe it's just the uber expensive tandems that have those features, along with the rohloff 14 speed gear hub on the back, those things are the size of a 250 watt hub motor, but are designed for high power going through them, able to shift under load and the shifts are seamless,

[soup]

Sort of puts the "no steering/brakes no vote" in the lie category

[Alan Braggins]

Synced is standard, but there are a few that allow independent freewheeling:

There are also a few with totally independent drive where one person drives the front wheel and the other the back, but that's probably even rarer, and I've only seen it on recumbents, or at least tandems where the front half is recumbent, like this one: