From CN live ticker stage 10:
Apparently he had to change bikes.
13:34 CEST 20.4km/135.6km to go
A group of 24 riders went clear ten kilometres into the stage, and are currently 1'32 ahead of the yellow jersey bunch. We'll get an ID on those soon. Fabian Wegmann (Gerolsteiner) is there and seemed to be having gear problems. Cyclingnews' Ben Atkins mentions he is on a prototype Shimano electronic gruppo and is stuck in top gear.
Apparently he had to change bikes.