Fastest Bike on Planet? Massive chainring, fixed-gear

It may look like a joke. But the 17-inch diameter chainring that graces a custom Donhou Bicycles build is real, and it has a special purpose: To propel a rider to 100mph under his own power.

Speed racer: Can a bike go 100mph on flat ground?

Debuted at the Bespoked Bristol custom-bike show last week, the bike is a fixed-gear model with a massive 104-tooth chainring. The special gear was made by Royce, a British bike parts firm.

Donhou bike captured attention at Bespoked Bristol show

Builder Tom Donhou said the impetus was “the simple desire to see how fast we can go” on a bike. According to reports on Bike Radar and an article on NPR, Donhou hopes to see a rider crank past 100mph on an airstrip and in the slipstream of a motorcycle or a car.

Builder Shinichi Konno of Cherubim takes a look at the Donhou bike

See the NPR story, “One Gear, One Goal,” for more on Donhou and the bike with the biggest chainring we’ve ever seen.

—Stephen Regenold

104-tooth chainring Donhou bike on display at the Bespoked Bristol show