Hubs for road, gravel, cyclocross, MTB or e-bikes
Bicycle hubs for rim brakes:
Hubs for rim brakes generally have axles designed for quick-release mounting. The mounting dimensions are 9x100 mm for front hubs and 10x130 mm for road bike rear hubs, and 10x135 mm for mountain bike and trekking bike rear hubs. The quick-release axles have a diameter of up to 5 mm. This is why some manufacturers also label the hubs as 5x100 mm and 5x130 mm. On very old steel road bike frames, the rear wheel mounting dimension of 10x126 mm is also still found. The 10x130 mm rear wheel hubs can be fitted there. The rear stays on these older frames are flexible enough to accommodate this.
- Rim brake hub quick-release fitting:
- Front wheel mounting width 9x100 mm for quick-release skewers with axles up to 5 mm thick
- Road bike, cyclocross rear wheel mounting width 10x130 mm for quick-release skewers with axles up to 5 mm thick
- MTB, trekking rear wheel mounting width 10x135 mm for quick-release skewers with axle thickness up to 5 mm
Bicycle hubs for disc brakes:
Hubs for disc brakes generally feature axles designed for thru-axle mounting. Many manufacturers allow these to be converted to quick-release mounting so they can also be used on older bikes with disc brakes. Even though disc brakes are the standard nowadays, there are still many mountain bikes, road bikes and touring bikes on the road that have frames and/or forks with quick-release dropouts.
- Disc brake hubs with quick-release and thru-axle mounting:
- Front wheel mounting width 9x100 mm for quick-release with axles up to 5 mm thick
- Road and cyclocross rear wheel mounting width 10x130 mm for quick-release with axles up to 5 mm thick
- MTB, gravel and touring rear wheel mounting width 10x135 mm for quick-release skewers with axles up to 5 mm thick
- Front wheel mounting width 9x100 mm for quick-release skewers with axles up to 5 mm thick
- Front wheel mounting width 12x100 mm for thru-axles with a 12 mm diameter
- Front wheel mounting width 15x100 mm for thru-axles with a 15 mm diameter
- Boost front wheel mounting width 15x110 mm for thru-axles with a diameter of 10 mm
- DH OS front wheel mounting width 20x110 mm for thru-axles with a 20 mm diameter, brake disc spacing 15 mm
- Superboost front wheel mounting width 20x110 mm for thru-axles with a diameter of 20 mm Brake disc spacing 1 mm
- Rear wheel mounting width 10x135 mm for quick-release skewers with a 5 mm thick axle
- Rear wheel mounting width 12x142 mm for thru-axles with a diameter of 12 mm, brake disc spacing 18 mm
- Boost rear wheel mounting width 12x148 mm for thru-axles with a diameter of 12 mm, brake disc spacing 18 mm
- Boost DH rear wheel mounting width 12x150 mm for thru-axles with a 12 mm diameter, brake disc spacing 11 mm
- SuperBoost rear wheel mounting width 12x157 mm for thru-axles with a diameter of 12 mm, brake disc spacing 18 mm
Boost bicycle hubs:
Boost hubs have wider hub bodies and hub flanges and brake disc mounts positioned further outwards. This allows for wheels with greater lateral stiffness due to the flatter spoke angle. The brake discs are also positioned further outwards. Consequently, Boost bicycle hubs cannot be fitted to frames or forks with narrower mounting dimensions. Even if the axle or hub end stops were adjusted, the brake disc would rub against the frame or fork.
Boost Standard 15x110mm and Boost 20x110mm front hubs:
These two mounting dimensions are identical apart from the inner axle diameter. The distance from the brake disc mount to the fork dropout is 10 mm. Therefore, Boost 15x110 and Boost 20x110 mm hubs can also be converted to the other mounting standard. Of course, this only works if the manufacturer has fitted the hubs with 20 mm axles and offers suitable end stops for the hubs.
Front wheel hub designations: Superboost, Boost DH, Boost OS, Boost 20, Boost for 20 mm thru-axle, BST20
Manufacturers use different designations for the Boost 20x110 mm mounting dimension. The decisive factors are the mounting width and the 10 mm clearance between the brake disc and the fork.
Front wheel hubs NonBoost DH OS 20x110mm:
Please note that there is a second front wheel hub mounting standard with 20x110 mm. This was found on older downhill forks, particularly double-crown suspension forks, and although it has the same hub mounting width, the brake disc mount is positioned further inwards than on Boost hubs. The distance between the brake disc and the fork dropout for the DH mounting dimension is 15 mm. Therefore, these hubs only fit into older forks. We strongly advise against using them in Boost 20x110 mm forks. Adapters are available to bridge the 5 mm gap. However, the bolts used to mount the brake disc then become too long and may fail. This must be avoided at all costs with a front brake. The Shimano Saint and Zee front hubs have this mounting dimension, as does the DT Swiss 350 DH OS.
Rear hubs Boost Standard 12x148 mm:
Hubs with the Boost 12x148 mm mounting dimension also only fit into frames with exactly this mounting. Cannondale has several frames in its range with the Boost 10x142 mm quick-release mounting. Boost 12x148 mm hubs can be converted to this mounting dimension. A prerequisite is, of course, that the hubs have replaceable end caps.
Rear hubs: Boost / DH 12x150mm and Super Boost 12x157mm
The Boost 12x150 mm and 12x157 mm hubs have the same hub body dimensions. The 150 mm hubs have a 7 mm shorter axle and hub end caps and can, provided the manufacturer has designed them to do so, be converted to the other dimension. A prerequisite is, of course, that the hubs have interchangeable end caps.
Thru-bolt axle assembly:
Thru-bolt mounting is often confused with quick-release mounting. The system was developed by DT Swiss when disc brakes first appeared on mountain bikes to achieve greater torsional stiffness in the frame/fork-wheel assembly.
The frames and forks are the same for both thru-bolt and quick-release mounting. However, the thru-bolt axle replaces the hub axle and is then secured with a locknut.
This is only possible with a few hub models, e.g. the DT Swiss rear hubs of the 350 and 240 series. However, DT Swiss does not offer suitable end caps for all freehub body types.
- Front wheel mounting width 9x100 mm for thru-axles with a 9 mm diameter and locknut
- Rear wheel mounting width 10x130/135 mm for thru-axles with a 10 mm diameter and locknut
