One can do this to adjust the chain tension without an eccentric BB.
Jim Merz Big Sur CA
On Mon, Jan 10, 2011 at 10:36 AM, Peter Brueggeman <
> In Dale's GP Wilson photos, there's a tandem photo showing an unattached
> chainring in the tandem chainline located between the captain and stoker
> chainrings. That's a new one to me. It looks like it is a couple of teeth
> larger than the front and rear chainrings.
> Is this something others have seen done, and does it accomplish anything
> other than looks?
> Peter Brueggeman
> La Jolla California USA