[geeks] Electric bike?

[Sheldon T. Hall]

 Francois Dion said ...
> On 7/18/06, Sheldon T. Hall <shel at tandem.artell.net> wrote:
> >
> > You need a co-axial arrangement through the regular bottom 
> > bracket.  The
> > motor drives a sleeve inside the BB, and the normal BB axle 
> > is inside of
> > that.  Two layers of bearings, of course: BB-sleeve, and 
> > sleeve-axle.  The
> > chainrings are on the sleeve, and a one-way clutch lets the 
> > BB axle (and
> > thus the pedals) drive the sleeve.
> 
> You'd think this would be a common tandem option. Didn't some BMX work
> this way? And then there was the Shimano positron, but I've actually
> never ever seen one. Went the way of the Biopace.

I've never seen this sort of BB arrangement on a "safety" bike, but some of
the epicyclically-geared Ordinaries had stuff like that in the hub of the
front wheel.  A not-so-dissimilar arrangement allowed multi-rider pacer
track bikes to have the rearmost rider's pedal axle run through the center
of the rear hub, yet be connected to the main drive system.

> I'm familiar with the Mercian, and I altough I read GB I tought CB:
> claud butler. Apparently there is no connection except both are
> british. Was Geoffrey Butler a frame builder?

Still is, judging from the website, but the shop's emphasis seems to be more
on retail trade now, rather than bespoke frames.

-Shel