Hambini Bottom Bracket Installation Instructions


This guide takes you through the fitting process of a Hambini Bottom Bracket. It supplements a video guide which is available below. I recommend you familiarize yourself with both before purchasing a Hambini Bottom Bracket. If you have any questions, please e-mail me and I will be on hand to answer any questions. support@hambini.com

Hambini Bottom brackets are much stiffer than any other bottom bracket that is commonly available, please install with caution to avoid damaging your bike frame. Hambini will not be liable for any frame damage caused by the installation of a Hambini BB

Crankset compatibility

  1. Shimano - no issues, all hambini BB's are a direct drop in for Shimano Hollowtech 2 systems.
  2. BB30 Extended / BB386 - Hambini BB's place the bearings at a nominal 90mm spacing. If your axle length is shorter than this, it will not work. Hambini BB30 extended BB's ARE NOT SUPPLIED WITH SHIMS. You may need some BB30 shims to take up any free play. It is impossible for this guide to cover every incarnation of BB30 and BB30 extended as there are many variations in the marketplace.
  3. SRAM GXP - Hambini BB's use a two bearing floating system as opposed to the OEM SRAM system of having the non drive side bearing fixed. SRAM used a fixed Non drive End bearing to avoid a Shimano patent infringement. To allow for the floating nature, Hambini BB's require preload to be adjusted by shimming. The crankset should be installed so there is just enough tightness on the crank axle bolt to prevent any play. Overtightening will destroy the bearings. Two methods of installing a Hambini BB in GXP systems are shown below. The first does not use a wave washer and is the preferred method used by a number of racing teams. This does require more frequent maintenance as the preload shims have to be adjusted as the bearing clearance increases. The second method functions like most standard bottom bracket/crankset combinations, both bearings are restrained in one direction, preload is by means of a wave washer. Please note Hambini GXP Bottom Brackets ARE NOT SUPPLIED WITH A WAVE WASHER
  4. Assembly Picture Assembly Picture

Installation Video

The video below shows you how to install a Hambini Bottom Bracket, there are some subtle differences between each bottom bracket depending on the application but the overall principle remains the same


All Hambini Bottom Brackets press in from the drive side (chain side) of the bike frame. They are designed in this way to maintain an accurate chainline that is within manufacturer (Shimano, SRAM etc) tolerances. The following need to be observed:

  • Bottom Bracket hole needs to be free of obstructions, usual obstructions are Di2 wires and bolts holding cable guides
  • The fitting tools that come with Hambini BB's are designed to be used with M12 studbar or presses. M12 or 1/2" studbar and nuts is acceptable, a press makes the job easier. Note: Park Tools professional press is approximately 16mm in Diameter and would require the Hambini adaptors to be drilled.
  • Usual respect of wearing safety equipment applies.
  • Any double lipped bottom bracket holes are unsuitable, this is usually only older model BB86 bike frames that have this issue, BB30/BB30A/PF30/PF30A/BBright usually meet this requirement. The picture below shows a double lipped bottom bracket, note the lip approximately 10mm into the bottom bracket shell Double Lipped Bottom Bracket

Mechanical Overview and replacement parts

All Hambini Bottom brackets have the same mechanical methodology. They consist of a one piece sleeve that is made of aluminium or a proprietary alloy, a pair of bearings and delrin spacers/sleeves. The bottom brackets use standard sized bearings which are designed to be replaced as and when they wear out. The bearings that are used are shown in the table below. The choice of bearing is dictated by the bottom bracket shell and not the crankset

Bottom Bracket Type BB30 BB30A PF30 PF30A BBright BB386 BB386 EVO BB86 / PF86
Bearing Type 6805 6805 6806 6806 6806 6805 6806 6805

If you have a custom hambini bottom bracket, please contact me and I will advise


It is highly recommended that the crankset is tried in the bottom bracket cartridge before the cartridge is inserted into the bike frame. Any issues with shimming can be identified at this stage rather than when the cartridge is in the bike frame.

Installation Method

  1. Make sure any Di2 wires, front mech cables and brake cables will not impinge on the installation of the Hambini Bottom Bracket. You should be able to see straight through the hole. Assemblypicture
  2. Prepare the frame by making sure all old adhesive has been removed and the surfaces are clean. Spray with cleaner and give it a thorough wiping. Assemblypicture
    Assembly Picture
  3. Assemble the installation tools as shown in the drawing below. The method of insertion can be a press or M12 studbar/nuts is also acceptable. It is very important to ensure the drive side fitting adaptor is pressing against a bearing and not a sleeve. If a sleeve is installed remove it. On some bottom brackets (usually those designed for a 30mm axle) there is no sleeve.
    Fitting Drawing
    Assembly Picture
  4. Bottom bracket shells are often slightly tapered, the edges of the bottom bracket are tigher than the insides, when the bottom bracket gets passed the first location landing, the press will go slack (this is normal)
  5. During installation, there may be some creaks or popping heard (especially on carbon frames). IF THE INSTALLATION BECOMES EXCESSIVELY TIGHT, PLEASE STOP AND CONTACT ME. The bottom brackets are designed to meet published specifications, however a lot of manufacturers make their apetures too tight or too loose
  6. Once the bottom bracket is ready to be pressed to locate on both landings, it is advisable to use retaining compound. On carbon frames, the use of Activator is required otherwise the retaining compound will not stick. (Loctite activator 7649, Loctite Medium Strength retaining compound 641). On the drive side, the retaining compound can be put directly on to the bottom bracket. On the non drive side, the retaining compound will need to be applied with a finger. Assembly Picture
    Assembly Picture
  7. Press the bottom bracket in until the drive side flange is flush with the bike frame. Ideally a check with a feeler gauge should be performed but a visual inspection is usually sufficient
    Assembly Picture
    Assembly Picture
  8. install delrin sleeves/spacers as appropriate (application specific) Assembly Picture
  9. Reinstall Crankset
    Assembly Picture

The list below shows the individual cross section drawings for all Hambini Bottom Brackets. Please pay careful attention to the orientation of any shims or spacers in the drawings.

BB Standard Size (diameter x length) Download Shell Drawing Download Hambini BB System Drawing SHIMANO
BB30 42x68 Download Here Download Here
PF30 46x68 Download Here Download Here
BB30A 42x73 Download Here Download Here
PF30A 46x73 Download Here Download Here
BBright 46x79 Download Here Download Here
BB386 EVO 46x86.5 Download Here Download Here
BB86 / PF86 41x86.5 Download Here Download Here
OSBB 42x61 Download Here link in here
Sachin Hambini Engineering, S. Varah, Unit 11386, 13 Freeland Park, Wareham Road, Poole, Dorset, UK BH16 6FH