Sit On – And Hold On

Aussie Stuart Hooper has for a few years been raising the world land speed record for a single-cylinder sit-on motorcycle – in other words, a speed machine with a normal riding position. This year at the Lake Gairdner Speed Week – South Australia’s equivalent to America’s annual event at Bonneville – Hooper once again took the record to new heights on his supercharged 732 cm3 Velocette.

 

After an initial sighting run of 177 mph (284,85 km/h), which nearly emptied the 10-litre fuel tank. The next run raised more fuel consumption problems with fluctuating cylinder head temperatures and eventually drowning the engine, which at least allowed the team to identify a very unusual fuel flow problem related to the bike’s specific installation.  For the third run the supercharger drive ratio was increased and the engine ran like a clock, resulting in a 188 mph (302,55 km/h) average. However, the Velo was not happy with major stability issues requiring a few minor suspension changes to eradicate. Then came the dream run…

 

“Using only half throttle and 5 000 r/min, she passed 150 mph (241,4 km/h) in a mile and then it was tuck in and twist the throttle to the stop,” recalls Hooper. “This time she ran straight as an arrow and the revs just kept building to 6 800 at the end of the measured miles. In fact, I kept the throttle wide for another untimed mile just for the hell of it and saw another 100 r/min on the old chronometric tachometer. Five miles absolutely flat out – 193,061 mph (310,7 km/h).”

 

Who said bikers are mad?

 

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