Hambini Bottom Bracket Bearing Maintenance

Introduction

This guide will cover basic bearing maintenance procedures related to generic bearings and specifically, Hambini Bottom Brackets.

Bearing Types

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 and it is possible for the user to select a bearing type at the point of purchase:

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. This bearing is not suitable for wet conditions unless it is serviced frequently.

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 friction significantly.

Bearing Maintenance Procedure

The maintenance of Hambini BB’s should be conducted as follows

  1. Remove the crank as per the manufacturer’s instructions.
  2. Remove any top hats and spacers from the Hambini BB
  3. DO NOT Remove the bearings unless you wish to replace the bearings. Pulling the bearings out by applying load through the rolling elements is likely to damage the bearing.
  4. 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.
  5. Flush the bearing out with alcohol or degreaser and allow it to evaporate.
  6. 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.
  7. Replace the seal
  8. 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.

General Cleaning

  • DO NOT SPRAY ANY DEGREASER NEAR THE BOTTOM BRACKET DURING NORMAL CLEANING, THIS INCLUDES CHAIN CLEANERS SUCH AS MUC OFF.
  • Cleaning with a light detergent such as dish soap and wiping it away will be sufficient.