Featured: World's Fastest Motorcycle Restored

World’s Fastest Motorcycle Restored

By Yoav Gilad
September 15, 2014

Photography by Yoav Gilad for Petrolicious

Triumph claimed the title of World’s Fastest Motorcycles for a fifteen-year period that began in 1955 with “The Devil’s Arrow.” A group of Texans, miffed by the fact that the Germans (NSU) held the crown, built a streamliner powered by a highly tuned, methanol-burning Thunderbird 650 Twin. It broke the German’s stranglehold on the land-speed record. NSU came back swinging but, after some adjustments and heavier-duty parts, the Texans once again recaptured the title about a month after the NSU’s new record.

And so it went with one Triumph besting another over the next few years until ultimately, the Gyronaut X-1 entered the scene in 1966. The fairing, designed by famed stylist Mr. Alex Tremulis (he worked for Cord, Duesenberg, Ford, and Tucker), was built by Mr. Vince Gardner (of Cord 810 fame) and would eventually set the bar for future streamliners not only because of its advanced styling, but also because it introduced features such as: a chrome-molybdenum frame, active “landing gear” (that was usually retracted around eighty MPH), a roll-bar, fire suppression system, and specially-designed Goodyear 250 mph+ tires.

When it finally hit Bonneville’s salt, driven by Triumph’s top-selling US dealer Mr. Bob Leppan, it shattered the record for gas-powered powered motorcycles by almost twenty percent. The new motorcycle land speed record? 245.667 MPH.

It was powered by two highly modified 641cc TR6 engines making seventy HP each and redlining at 8200 rpm. The record held for four years and the Gyronaut nearly broke it again, but crashed at an alleged 280 MPH! It was stored following the crash and was only recently restored.

The whole motorcycle was gone through with the chassis being restored by Jefferson Motor Service in Detroit, and the engines were checked and rebuilt by the Triumph experts at Performance Cycle in Diamond Springs, California. In an interesting twist, the fiberglass body was restored by Rob Ida Concepts where two of Mr. Preston Tucker’s, Gyronaut-designer Tremulis’s former employer, great-grandchildren work.

Furthermore, the Gyronaut’s original pinstriper, Mr. “Wild” Bill Betz, was brought in to recreate his original work. Following the crash the only panel that remained undamaged was the access panel on the Gyronaut’s right, rear quarter. It happened to bear Betz’s signature. Today it is the only original, untocuhed paint on the motorcycle.

Seeing the bike in person at yesterday’s Palos Verdes Concours, the most impressive features were the completely aeronautical form that it has, looking like a crash-landed fighter-plane, and the rider’s seating position: Leppan’s knees would have been aligned with his shoulders. And while it looks endless in photos, the Gyronaut is actually not as long as one might expect.

It no longer holds the record for World’s Fastest Motorcycle, but for a period asserted Triumph’s dominance in the motorcycling universe and brought together important designers and engineers to show what could be accomplished with two engines and two wheels.

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Herb Wilson
Herb Wilson
6 years ago

I should have went by Wild Bill’s the day he pinstriped it. i happened to call on the day they were picking it up from his shop. The twelve point nuts holding the carbs on are almost impossible to remove. Almost! I was at TT Kenny’s house when Bob came over and the engines were getting disassembled in their pod. The original front tire/wheel was there also. The tire that Goodyear had made specifically for this bike was hard as a rock. It’s a rear sprung hub Triumph wheel converted to a front hub steering wheel.

Herb Wilson
Herb Wilson
6 years ago
Reply to  Herb Wilson

The engines were 650cc pre-units. The top ends on it now are later 750cc on the original pre-unit lowers. That’s how it was on the last attempt. The Author should have know these details but probably talked to the wrong person. Astute Triumph fans probably caught that detail.

James Grabow
James Grabow
7 years ago

I saw this at The Race of Gentlemen a couple of months ago. Simply amazing how much automotive and motorcycle history is hidden away for so long, and how it can pop up and fall into place so perfectly at the right event.

Christopher Gay
Christopher Gay
9 years ago

Wow! What an interesting piece of machinery. It is too cool that the panel holding Mr. Betz’s signature survived the impact. Looks like a fun project.

And speaking of impact, just the thought of crashing at speed in that thing, surrounded only by fiberglass and a small tube frame, gives me the shudders. Kinda like a P917 on the Mulsanne. Yikes!

Thanks for sharing.

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