Gone are the rear sprockets, front chainrings, both derailleurs and the chain, along with all the maintenance issues associated with this sort of setup. Instead, there’s a rubber belt and aluminium sprocket with essentially invisible gearing. This gives an impressive 525 percent range, approximately equal to 24×32 at the low end and 44×11 at the top end.
The santos belt drive that lasted 12,000 miles:Jeff Jones/BikeRadar
Bowthorpe told BikeRadar that he had “lots of things to worry about” on his journey but fixing the drivetrain wasn’t one of them. In fact, he only had to replace the belt once because of a misalignment problem.
The second belt, fitted in Perth, Australia, survived the next 12,000 miles and Bowthorpe reckons it still has several thousand more miles left in it. By comparison, he told us that using a standard touring setup he would have gone through “three or four chains” in that distance.
Rain doesn’t affect the belt drive because unlike a chain, there are no moving parts for it to get into. There’s no need for lubrication either but Bowthorpe said it still felt smoother than a chain and cassette.
Santos general manager Robbert Rutgrink was justifiably happy with the performance of the Santos belt drive. It’s difficult to imagine a more rigorous test for a piece of bicycle technology than riding it around the world, and yet it survived remarkably well.
Rutgrink told us that Bowthorpe had tested the second version of the belt. In the meantime, Santos have improved the coating for longer wear, and they’re now on to version six.
Belt drives may not spell the end of the bicycle chain just yet but we can see them becoming more popular, especially for touring and commuting.
The front wheel was a 36 spoked rigida rim built on a schmid son dynamo hub:Jeff Jones/BikeRadar
The front wheel: 26″ Rigida rim built on a Schmidt Son dynamo hub with a Schwalbe Marathon XR tyre
There were several other features on Bowthorpe’s bike that caught our eye. Firstly, the wheels were built using 26in Rigida rims with 36 spokes on the front but only 32 on the rear.
Bowthorpe explained that the Rohloff rear hub enabled the wheel to be built symmetrically. That meant it was stronger than a normal wheel which has shorter spokes on the drive side than on the non-drive side.
Mounted on the wheels were a set of Schwalbe Marathon XR tyres, which lasted an amazing 12,000 miles. Braking was courtesy of a set of Magura hydraulic rim brakes, which provided enough power to stop the fully laden touring bike and its rider.
The yellow box is a home built transformer that converts ac to dc, thus can be used to power leds and charge james’s phone and ipod: the yellow box is a home built transformer that converts ac to dc, thus can be used to power leds and charge james’s phone and ipodJeff Jones/BikeRadar
The home built front light set up, including transformer
Bowthorpe told us that he ended up doing half of his riding in the dark, which meant he needed a good set of lights and a reliable power source.
He used a Schmidt Son dynamo front hub to convert some of his leg power to electricity. That powered a standard dynamo lamp and a pair of 12V LEDs that were mounted on a box on the handlebars.
The box was actually a home-built transformer that could convert the AC produced by the hub into DC for the LEDs. He could also use it to charge his mobile phone and iPod while on the move.
The transformer and chargers: the transformer and chargersJeff Jones/BikeRadar
The transformer could also be used to recharge an iPod and a mobile phone
The ipod was a key piece of equipment: the ipod was a key piece of equipmentJeff Jones/BikeRadar
…and you can do with a bit of music when you’re cycling around the world
James relied on a brooks saddle to carry him around the world: james relied on a brooks saddle to carry him around the worldJeff Jones/BikeRadar
Last but not least, when you’re riding up to 150 miles a day, you don’t want any saddle issues. Bowthorpe’s choice of a Brooks leather saddle circumvented this potentially crippling problem.
Stay tuned to BikeRadar for an interview with James Bowthorpe, which will be posted in the coming days.