Tom Hayes wrote:
> Does anyone know what the following Campagnolo item is:
> http://ebay.com/
> alternatively, Ebay number:380150117371.
>
> It appears to be a front derailleur or chain guide of some sort as the
> seller states. Is there a piece missing? Under what circumstances would
> this mechanism be used?
>
It is a chainkeeper, to be used with bikes with a single ring up front and a spring loaded chaintensioner somewhere in the driveline. Bumps could set up a horizontal wave in the chain, and then the chain will derail. This device will prevent this (as will any front derailleur). It looks complete.
-- mvg
Marten Gerritsen