European Athletics Mens Marathon

[Bryan]

This is actually on topic!

Did anyone else see the back to back tandem riding alongside the leaders towards the end of the race yesterday? Must admit I've never seen one 'in action' and couldn't work out how the stoker contributed to the forward motion of the bike (the stoker on this tandem quite often didn't contrivute anyway .

So how to back to backs work?

Bryan

 

[Dave Larrington]

Bryan wrote:
> This is actually on topic!
>
> Did anyone else see the back to back tandem riding alongside the
> leaders towards the end of the race yesterday? Must admit I've never
> seen one 'in action' and couldn't work out how the stoker contributed
> to the forward motion of the bike (the stoker on this tandem quite
> often didn't contrivute anyway .
>
> So how to back to backs work?

Some of them - at least the Dark Side variety[1] - have two-wheel drive,
with each rider having a completely independent powertrain. Others - such
as the Ostrad Janus and MicWic Delta - are rear-wheel drive, and done just
like any other tandem, with a crossover drive somewhere. In both cases,
though, the stoker's chain has to do something clever in order to reverse
its motion. Usually achieved with idlers to get a figure-8 routing, though
the Flevo had a different approach:

<URL:http://www.legslarry.beerdrinkers.co.uk/images/tandems/large/Flevo.jpg>

Stoker's cockpit on the left.

1 - photo of BTB uprigh tandem in latest CTC rag

--
Dave Larrington
<http://www.legslarry.beerdrinkers.co.uk>
Never give a gun to ducks.