Co-Motion’s been building tandems for quite some time, so it should come as no surprise they took home an award this year.
What was more of a surprise was not one, but two different gravel-style road bikes with alternative gearing designs. Usually we’ll see those with larger collections show off one bike with something like an internally geared hub or gear box, just to show what they can do. Co-Motion had both, and both were fine examples…
The Siskiyou Rohloff 650B puts a Rohloff 14-speed internally geared hub on their Reynolds steel adventure bike, setting the twist shifter inboard of the handlebar tape. It’s driven with a Gates Belt Drive, and between the cogs is an all-new chainstay yoke that improves tire clearance.
It uses a similarly clever cable routing design as the new Divide Pinion:
The Divide is their 29er drop bar travel and adventure bike, also made of Reynolds steel tubing.
This new Divide Pinion replaces standard gears with an internal gear box providing a whopping 18 speeds.
A modified twist shifter controls the gearing…
…with two sets of coupled cables running along the down tube. They had to switch each cable’s position in relation from the shifter to the gear box, and the cable couplers make that possible.
It’s all making things turn through an oversized Gates rear cog and Co-Motion exclusive stainless steel sliding dropouts.
This racy number took home the Best Tandem award for NAHBS 2016 thanks to a super clean, high end build, excellent paint and solid construction.
The Java 29er tandem may have big tires but gets FSA road cranks and Ultegra derailleurs. Rack and fender mounts adorn the zonally butted tubes. Retail is $5,395.
How hard is it to weld a stainless dropout to a steel frame?
It just requires very even application of the filler wire to ensure consistent weld strength around the circumference of the tube. While that’s the goal with any weld, it’s especially important when welding different steel alloys to each other. Plus some argon back purging to make sure the internal side of the weld is free of oxidation. Although almost all builders will be back purging with any thin wall tubes, stainless or not. I imagine that a brand as experienced as Co-motion would have no problem with any of that, just look how tidy the down tube weld is to the pinion housing on that bike.
Easier than changing the drive belt after the dropout is welded in place I’d imagine.
They finally decided to show off a bike with a Pinion gearbox! My bank account is fearing for its safety…