This one falls very soundly into the don't-try-this-at-home category: Frenchman François Gissy has set a new world speed record in the rocket-powered bicycle category, reaching 263 kilometres per hour on a disused runway in Munchhouse in the Alsace. That's 163.4mph in old money.
If you can't quite get your head around how quick that is, then have a quick gander at this video of the record attempt. It's not a discipline we think we'll be getting into any time soon.
The rocket in question is powered by hydrogen peroxide, which is forced over a catalytic converter at high pressure to produce water and oxygen. That generates enough propulsion to reach these insane speeds.
Perhaps the most astonishing thing about all this is that the human-powered bicycle land speed record is even higher than Gissy's top speed under rocket power. The current record is held by Dutch rider Fred Rompelberg and it stands at 268.831 km/h (166.9 mph). Rommelberg was motor-paced behind a modified dragster on the Bonneville salt flats.
Dave is a founding father of road.cc, having previously worked on Cycling Plus and What Mountain Bike magazines back in the day. He also writes about e-bikes for our sister publication ebiketips. He's won three mountain bike bog snorkelling World Championships, and races at the back of the third cats.