On Sun, 26 Aug 2007 22:51:02 +0200, Artemisia wrote:

Tim Hall wrote:
So yes, Busch & Muller Dymotec 6 with Standlight. Considerably cheaper
than the SON hub option, and I've read postings that say the drag is
almost negligeable. Do you know if the drag can be removed completely
when the dynamo is off, or is there always some?

As it's a tyre driven dynamo, "off" is acheived by moving the dynamo a
small distance from the tyre. "On" is acheived by moving it such that
the roller on the end of the dynamo rubs against the tyre. The
Dymotec has a small switch to do the turning on, by releasing a
spring.

The upshot of all this is that when it is off, it's not in contact
with the tyre, so there is no drag.


Tim