Jon Bendtsen wrote:
Tom Sherman wrote:
TandemFan wrote:

[cross-posted to ARBR for Perry Butler's amusement]

We have a R[ANS] Screamer tandem and there are a few idler rollers for
the chain. An outfit sells toothed idlers for about $250:
http://www.terracycle.com/Merchant2/...Code=IdlersALL


They have a long blurb on why they are better:

http://www.terracycle.com/Merchant2/...d e=IdlersALL


What's the scoop? Does it make any difference at all, or are we going
to go faster?

Someone needs to tell Pat Franz that it is "RANS" and not "Rans".

While the manufacturers in question are trying to meet a price point
for their bicycles, they are not going to be putting junk chain idlers
on their bicycles [1]. Therefore, while there is room for improvement,
the gains will likely be small as drive-train friction is a small
component of total non-conservative losses, even on a recumbent with a
complicated chain-line.

Why not avoid idlers and recumbents with complicated chain-lines?

It might not (yet) be possible with a tandem, but for a single
rider bike, cruzbike offers a short normal chain-line.

And introduces a whole other set of compromises in seating position,
weight distribution, traction on steep hills, etc. Long chain lines are
not necessarily a bad thing, as several issues with short chain lines go
away that make wide range gearing difficult.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful