Saturday, 8 August 2015

How fast can a person go on a bicycle? from motorpacing to rocket bikes


 The fastest unassisted human powered bike world record was 82.8Mph by Sam Whittingham set in 2009. Barbara Buatois managed 75.7Mph in 2010. In 2011, a college team from TU-Delft in the Netherlands became the 2nd fastest all-time with a rider, Sebastian Bowier: 80.5Mph. These bike require serious gearing



However you can go faster with assistance. Way back in 1979 Jean Claude Rude was an ambitious man and the French cyclist wanted to break the world bicycle speed record. In order to become the world’s fastest on bike, he had to go faster than his fellow countryman José Meiffret who had set the record at an impressive 204.7km/h (127.2mph) in 1962. This amazing speed was achieved on the German Autobahn, presumably closed for other traffic, near Freiburg where Meiffret was riding in the slipstream of a Mercedes-Benz 300 SL. But at a speed of 160km/h (100mph) when suddenly Jean Claude’s rear tire exploded and was torn from the wheel.



Forward to 2013, Guy Martin did 110mph using motor pacing (sheltering behind a truck)!






The motorcycle racer and lorry mechanic from Grimsby was filmed by Channel 4 last year, as he attacked the record of 110mph set by Dave Le Grys on the unopened M42 motorway in 1986.
With no unopened motorways available, Martin opted for Pendine Sands in South Wales, a seven-mile stretch of beach with a history of record breaking: it was first used in 1924 by Malcolm Campbell to reach 146mph in his Bluebird. But pedalling a pushbike on sand at over 100mph is hairier than Martin’s cheeks.

Using a similar compound gear system to Dave Le Grys’s original 1985 bike, built by Cliff Shrubb, Hope supplied custom cranks, bottom brackets and two 60-tooth chainrings. With a 16t sprocket on the seat tube and 15t on the rear wheel, the wheel turned 15 times for every pedal revolution. At 112mph, Martin’s cadence was 97rpm, and the wheel was spinning at 1,460r
 
 


Olympic Cyclist and IRONMAN triathlon winner, John Howard set a 152.2 Miles per Hour speed record at the Bonneville Salt Flats near Wendover, Utah on July 20, 1985. He is drafting in the wake of a 500 Horsepower Streamliner. This type of human powered record is called motor pacing. The pace vehicle was modified by adding a large tail fairing to the 337 MPH record holding Vesco Streamliner. The fairing keeps the wind off John and reduces the aerodynamic drag he is pedaling against to near nothing.
This type of record was invented by Charles "Mile-a-Minute Murphy" who drafted a train to set a 60 MPH record at the turn of the century. A mile of plywood sheets was attached to the railroad ties, so Charles would have a smooth surface. He had to be lifted onto the train just before they ran out of the plywood surface!
The previous record holder at 138.8 MPH set in 1973 was physician, Dr. Allan Abbott, a cycling enthusiast and motorcycle racer.

 
 

What about powered bikes? Now this is crazy. Frenchman Francois Gissy hit 285 km/h (177 mph) on a rocket-powered bicycle. Now, at the Circuit Paul Ricard in the South of France, he's knocked his own world record out of the park. Dialing in a massive 4.5 kN of thrust, which generates roughly the equivalent of 560 horsepower, Gissy took his rickety-looking rocket bike up to a monstrous 333 km/h (207 mph), hitting top speed in just 4.8 seconds and generating about 1.96 Gs worth of acceleration.


No comments:

Post a Comment