This guide will cover basic bearing maintenance procedures related to generic bearings and more specifically Hambini Bottom Brackets
The maintenance regime for Hambini bottom brackets is largely dictated by the bearings that are fitted into the bottom bracket. Broadly speaking there are two types:
Non Contacting Seal (Racing Bottom Brackets)
Non Contact seal bearings are typically NTN, NSK or SKF. There is a very small gap between the seal and the inner race that facilitates exceptionally low levels of friction.
Full Contact Seal (Classic, MTB and heavy use)
Fully contacting seal bearings are typically NSK, NTN, SKF, FAG, Koyo and others. They have a rubber seal which touches the inner race. This provides good levels of resistance against dirt ingress but increases the friction significantly.
Bearing Maintenance Procedure
The maintenance of Hambini BB’s should be conducted as follows
- Remove the crank as per manufacturer’s instructions
- Remove any top hats and spacers from the Hambini BB
- DO NOT Remove the bearings unless you wish to replace the bearings
- Remove the bearing seal whilst the bearing is still in the Hambini Cartridge, only the outer seals will be accessible. Bearing seals must always be removed from the inner race towards the outer race
- Flush the bearing out with alcohol or degreaser and allow to evaporate
- Refill the bearing with 1/3 grease, do not overfill. Excessive grease and a lack of free space can cause the cage to be prevented from moving, resulting in skidding.
- Replace the seal
- Reassemble the crank
The recommended Grease type is NLGI 00 for racing applications, NLGI 0 or higher for extended use.
The maintenance frequency will be dictated by the riding conditions and the type of bearings installed. No hard and finite value can be given with timescales or distance travelled.
- DO NOT SPRAY ANY DEGREASER NEAR THE BOTTOM BRACKET DURING NORMAL CLEANING,
- Cleaning with a light detergent such as dish soap and wiping away will be sufficient.