The bicycle is what can be referred to as a mature technology. While iterative improvements have advanced the art, it has existed for a very long time in largely similar configurations. Despite having generally accepted design parameters, nothing has stopped designers from attempting to build a better mousetrap.
One such example is this Alter Cycles frame we spotted at the Barry Roubaix Gravel Race.
Made locally in Grand Haven, MI and designed by Rick Vaughn, one of the minds behind the Slingshot mountain bike in the 1990s, the frame features a radical departure from convention and replaces the down tube with a rider-tuned leaf spring.
The spring tube is made using HS90 steel and comes in three tunings selected based on rider weight. The rest of the frame is aluminum and features a specially shaped top tube to encourage vertical flex in the frame, which is intended to both enhance rider comfort and aid in propulsion by storing and releasing energy from pedaling.
This particular bike was a demo provided to local rider Steve Westdorp and as such, was built in an economical configuration. Shifting was handled by Shimano Tiagra 4600 shifters and derailleurs, which moved the chain over an 11-32t cassette. Up front the bike was equipped with an FSA Gossamer 50/34t crankset. Power was applied with Shimano XT PD-M8020 trail pedals.
The frame is disc specific and was equipped with TRP Spyre cable-actuated brakes.
Rolling stock consisted of unmarked alloy wheels with Arisun Dual Action tires in 700c x 32mm. Unsurprisingly for a demo bike, the remaining components were largely unmarked OEM pieces, with the exception of a Salsa Cowbell handlebar.
While this particular frame is intended as a commuter bike, Westdorp has used it in a handful of local gravel events and had praise for its performance at Barry Roubaix. “I think it could be an amazing gravel bike,” he told Cyclocross Magazine.
We will be keeping our eyes out for more of the unique bikes at future Michigan events like the Coast to Coast Gravel Grinder.
For more on Westdorp’s bike, see the photo gallery and specs below.