Bottom bracket gearbox on a touring bike?

Pinion 18 speed gearboxes, which were developed for downhill gravity bikes, are now designed into touring and city bikes.

tanami xplore

Downhill racing bikes are designed for shooting quickly down a steep, bumpy mountains while the rider navigates around and steamrolls over trees, rocks, wildlife, sports photographers, and other obstacles. They’re usually shuttled to the top of the hill so these bikes have big suspension, heavy frames and lack low gears, but some gearing is still used for the flat sections of the trail.

One of the problems with gravity racing is the delicate dangly bits like derailleurs sometimes snag on tree limbs, rocks, camera straps, etc. To solve this problem, some downhill riders use Rohloff Speedhubs.

Pinion 18 speed gearbox

Some engineers don’t like adding five pounds of unsprung weight to the rear wheel, so they designed this crazy gearbox that puts 18 speeds inside the proprietary bottom bracket. You put that six pounds of sprung mass near the center of the bike for superior handling, while you put a sturdy single speed axle on your undished rear wheel.

Suntour did something similar (if much uglier) with their abortive VBoxx gearbox. This newer Pinion system looks much cleaner.

I don’t follow gravity riding so I have no idea if any American brands have adopted this design for their bikes or not, but I’ve seen them on French and German designed bikes which are resold by the occasional American importer.

The German bike company Tout Terrain are highly regarding among touring cyclists for their high quality frames and builds. Adam Pressler in Dallas recently brought the Tout Terrain’s Tanami Xplor shown above to my attention. This 29er CroMo frame (what the Germans call 28 inches, and which roadies call 700c) with integrated stainless rack and Tout Terrain Blade SL fork, which works with the Schmidt dynohub so you can remove the front tire without disconnecting wires, pushes a lot of the right buttons for me.

This Tanami Xplor, along with its 26 inch little brother the Silkroad Xplor, are designed for the Pinion 18 speed gear box. Hey, look! Peter White imports and stocks Tout Terrain bikes, including these Pinion gearbox models.

The Koga Signature World Traveler 29er is available in a Pinion gearbox configuration, with a belt drive option as well.

For German hipsters, Schindelhauer sells the Ludgwig XVIII which combines the simplicity and look of American low-cost alloy fixed-gear freestyle bikes with German over-engineering for this €5000 bike. That 6,000 American clams for Euro-urban Zen simplicity.

Schindelhauer Ludwig 18 with Pinion gearbox

The usage case for gearboxes on gravity bikes seems pretty clear. Touring bikes make some sense, because you don’t want to bust an axle on a loaded bike in an ox track 500 miles from the nearest bike shop. City bikes, I’m not so sure about.

Your opinion?

Important Note: SF Bike Expo happens a week from Saturday. Be there.

2 Comments

  • November 12, 2014 - 9:37 pm | Permalink

    How wide a range does the gearbox have? Is it wider than the range available for planetary hub gears? What about efficiency? Derailleurs have very high mechanical efficiency, planetary hub gears adequate efficiency—these? (Downhill bicyclists don’t care much about efficiency, but for touring and city riding in hilly cities, efficiency may matter.)

    The gearboxes would make sense on a city bike if there was a chain guard, but none of these bikes show a chain guard.

  • November 13, 2014 - 8:11 am | Permalink

    I can’t see a lot of advantage for bikes that have to go up hills and over distances where there isn’t a lot of brush.

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