Breaking Away: Apt Cycles Pinion Belter Travel Bike

Breaking Away: Apt Cycles Pinion Belter Travel Bike

Dave Lindberg is a hobbyist builder who brazes steel frames out of his garage in Portland, Oregon. He has just completed his sixth bicycle, and with this third of his own — a Pinion-gearboxed, belt-driven travel bike — he has continued the trend of experimenting with unique design concepts and custom components.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

Initially inspired by the lively cycling and frame building scene in Portland, his brother Steven TIG welded a frame at the United Bicycle Institute. The two bought an Anvil frame jig together and started amassing the tools needed to hand file miters, fillet braze, finish tubes, and build wheels.

Three years ago, Dave constructed a belt drive fixed gear, equipped with hidden slider dropouts using one-off steel castings. He later made his 225km per week ‘daily driver,’ a 1×11 commuter with internal routing, customised dynamo lighting, and an integrated rear rack brazed directly to the frame.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

With this latest build, he wanted a bicycle he could fly to ride events without paying oversize fees. Exploring breakaway options and couplers, this proved the perfect excuse to try a Pinion gearbox, since the frame could split where it mounts. With a Gates belt drive, it would easily pack into a suitcase without any exposed grease.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

His design fastens the main triangle to the front mounting screws of the gearbox, then affixes a chain stay bridge to the rear, slotted for a few millimetres tension adjustment. Not wanting the gearbox itself to bear any twisting load of these two overlapped subassemblies, an aluminium brace resides between them.

The stays all disconnect at the Paragon Machine Works PolyDrop axle inserts, and the seat stays are capped with CNC machined ends that bolt together around the seat tube. This completes the rear triangle and clamps the seat post at the same time. Not required to intersect a BB shell, the seat tube can sit at a slack angle and tuck the wheel for a tighter rear centre.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

“I’m a little surprised how well it all worked out,” he admits. “Two weeks of riding plus a century in California, and nothing has budged or made a sound.” Meant to be ridden in fair weather, the chromoly steel is gun blue finished, as this interface is not very conducive to paint.

Ironically enough, it rained all day on his trip south — but the joints fared nicely despite the wet. Future iterations of this concept might be done in stainless steel.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

The Pinion C1.6 used here is the company’s lightest and least expensive option, but is not quite intended for use on a road bike. This complete build tips the scales at 11.5kg, with 1.8kg in the gearbox alone.

The 295% range is adequate for climbs and descents, but the 24% increments between the six gears — along with the coarse freewheel ratchet at the cranks — “definitely took some getting used to,” he says. Only available with a twist shifter for MTB bars, Dave had to design his own stem mount components to combine with the Pinion parts.

Working by day as a mechanical design engineer, he has access to CAD software and a Carbon M2 DLS printer, which directly produced the end-use parts.

Breaking Away: Apt Cycles Pinion Belter Travel Bike

Now with a number of successful new design ideas implemented, he is eager to try more on upcoming builds. Given the fairly saturated market for custom frame building in Oregon, this will likely remain only a part-time hobby for either of the brothers.

But if you’re interested in something different and innovative — and have the patience to wait for it — they might be able to build you a custom bicycle that is apt for your needs as well.

Apt Cycles Instagram

Breaking Away: Apt Cycles Pinion Belter Travel Bike