Bicycle bearings reduce pedaling energy
A new bottom bracket – the bearing that connects the crank set to the bicycle – is said to reduce friction, uses plastic to save weight and resist corrosion, and is sealed for life.
Schaeffler's BB29 FAG bottom bracket employs an optimised bearing design and does not need to be braced in the frame. It s intended for city and touring bicycles and employs a glass fibre reinforced plastic housing and a shaft that is coated with a special corrosion protection agent, which provides corrosion resistance in salt spray tests of more than 200 hours.
The two ball bearings are sealed on both sides and lubricated for life.
The profile of the housing is suitable for holding both FAG tools (external) and Shimano tools (internal). The reduced diameter in the centre of the bearing unit creates sufficient spaces for inserting cables for lights or other electrical connections on the cycle. The unit is available for axle lengths of 119, 122.5 and 127mm. There is a TC version with a flange on the frame and a TO version without a flange.
The new design is the latest in a long series of improvements in this component, which in spite of the forces imposed on it by riders, has to maintain its shape and keep friction down while minimising weight and maximising reliability. The BB29 complements Schaeffler's BBL66 bottom bracket for load carrying cycles, such as those used by the German postal service and FAG 'Cronitect' hybrid bearings for racing bikes.
