Viral Optimist - Bentonville's Titanium Belt-Drive, Gearbox Trail Bike Flexes Its Muscles

The Viral Optimist is a full-suspension trail bike built with a titanium front triangle and a CNC-machined aluminum rear triangle. It uses 145mm of rear travel and a 150mm front fork. The suspension is a classic single-pivot layout with a linkage-driven shock, using a flex-pivot element called the “Faux Bar.” A small flexible titanium plate above the rear dropout allows the chainstay swingarm and seatstays to rotate independently and also provides an entry point for the belt drive. The aluminum rear triangle maintains stiffness for belt alignment through suspension travel, addressing belt-drive sensitivity to alignment and fixed belt lengths.

"The Optimist is a full-suspension trail bike that pairs 145mm of rear travel to a 150mm front fork. But it's Optimist's slick flex pivot, the electronic shift Pinion gearbox, Gates belt-drive, and mix of 3D-printed titanium up front & CNC-machined aluminum out back that make it unique."

"Behind that Smart.Shift Pinion gearbox, the Optimist features a classic single-pivot suspension design with a linkage-driven shock, that Viral refers to as the "Faux Bar". Their special take on the Faux Bar concept features a small flexible titanium plate ( see below) just above the rear dropout on the seatstays, acting as a flex pivot. It actually serves two purposes."

"It allows the chainstay swingarm & seatstays to rotate independently, while also providing an entry point for the belt drive system. Pretty cool. The aluminum rear triangle provides the stiffness needed to maintain belt alignment throughout the bike's travel."

"Not sure if you've thought about it, but belt-drives are a bit picky. They need near-perfect alignment to work smoothly, which inherently flexy titanium often can't manage without being significantly over-built. Plus, the belts come in fixed lengths and require a significant wrap"

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