A first prototype (shown in the video above) has been completed and is undergoing testing. It has four speeds with an overall range of 327%. The gear ratios are as follows (input : output):

  • First gear: 1 : 1

  • Second gear: 1 : 1.89

  • Third gear: 1 : 2.57

  • Fourth gear: 1 : 3.27

Gear shifting is accomplished through a cam mechanism on the right side of the hub that moves two clutch members that hold successive ring gears stationary, producing the required gear.

For testing, the hub is currently mounted in the front wheel of the direct-drive recumbent bicycle shown below. More general information about direct-drive recumbent bicycles is given in the “Direct-drive” page.

The Velotegra hub is not restricted to direct-drive. With minor adaptations, the hub may be mounted in the rear wheel of a regular chain-driven bike.


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The tests have shown reliable operation under heavy loads and in all ratios. Being a first prototype, the hub is designed for proof-of-concept rather than for low weight and bulk, so there is much scope for making the hub lighter and more compact.

The main component parts of the first prototype are shown below.

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