A blow-off valve, shown here below the exhaust outlet, prevents surge loading from damagin
My first challenge was learning to ride the bike, which wasn't easy. The riding position is radically different from a stock Bonneville, with a low, cut-down fuel tank and the seat swept up at the back to make room for the turbo behind the engine. The footpegs were relocated a good distance rearward to create a more aerodynamic riding position, which forces you to change gears with your left toe pointed at the ground. There's no front brake, but no rear brake pedal either-squeezing the lever works the rear stopper. The hopelessly inaccurate stock Triumph tach was blanked off, so I shifted according to the boost gauge and the 9300-rpm rev limiter.
Capri set the turbo to produce a serious 17 psi of boost and it came on very suddenly, hitting the rev limiter very quickly. The awkward shifter made grabbing the next gear difficult, but I eventually sorted it out. My first pass was a modest 155 mph-not especially impressive considering I had earlier gone 153 mph on Capri's naturally aspirated Triumph Thruxton, establishing two new FIM world records in the process. My return run, however, was significantly more promising: 171.624 mph. That's more like it!
This turned out to be as close as we got all week to a speed that was representative of the bike's true potential. I was eventually able to set a new FIM world speed record for the flying mile at 165.405 mph-and 165.672 mph for the flying kilometer-but trying to improve that mark only resulted in breakdowns. First the throttle bodies were blown clear off their intake stubs, unable to withstand so much boost! Safety-wiring these on resumed normal service, but on the next pass the shift linkage disintegrated, forcing me to abort that run, too.
This could have been interpreted as another message from Don Vesco's ghost, but Capri wanted to make at least one pass at over 180 mph. With just 35 minutes remaining before the 2 p.m. shutdown, we staged again. Just as the starter waved me onto the course, Andrew rushed out and stopped me. He'd spotted the foil-wrapped fuel lines leaking. And so it was for another year.
With sore heads from an impromptu celebration of the Bonneville's 50th birthday the night before, the South Bay Triumph team left the salt flats already planning for this summer's return attempt. "For sure the Turbo is a 180-mph motorcycle," says Capri. We just need Vesco's ghost on our side this time.
"Like rolling over millions of tiny ball bearings" is a pretty accurate description of rid
Running a highly tuned engine at peak revs for miles at a time inevitably skews the wrench
The South Bay Triumph racing team (left to right): Andrew Cathcart, Alan Cathcart, Roger R