We’ve all heard it said somewhere that Harley’s aren’t fast and can’t go round corners. Well here’s one that did, and still does, and at times can fly. Read on to find out more about the legendary XR750.
We’ve all heard it said somewhere that Harley’s aren’t fast and can’t go round corners. Well here’s one that did, and still does, and at times can fly. It’s the legendary Harley-Davidson XR750. Is it a raw and agile racer or just heavy American iron? At over 335lbs you’d most likely say the latter; but believe it or not, the legendary XR750 is an exciting and vital part of motorcycle racing history - one of the most successful racing motorcycles of all time.
The XR750 was built in 1970 to compete in American Dirt Track racing, more commonly known in the USA as Flat Track racing. The bike still retains the same essential and raw look. Just like the very first machine that rolled out of Harley’s race shop all those years ago, and to this day it still dominates AMA Dirt Track Championships.
Top American riders like Randy Mamola, Eddie Lawson, Kenny Roberts, Kevin Schwantz, and more recently MotoGP’s very own Nicky Hayden, all developed their skills on oval Dirt Track circuits. It’s just the rider, a bike and a whole lot of courage. Elbow-to-elbow they fight it out at speeds of up to 130mph – with no front brakes, sliding through corners just millimetres away from the barriers. It’s like our Speedway, but there are usually around 18 riders and they’ll be close enough to swap sponsor’s stickers for over 25 laps!
There are many riders associated with the XR750, such as Jay Springsteen, Chris Carr and record nine times AMA Grand National Champion, Scott Parker. But there are none braver and more talented than the late, great Cal Rayborn; his name is synonymous with the XR750. He not only rode this bike on dirt ovals, but showed what a versatile machine it really was in its road racing form: the XRTT.
Cal accomplished a tremendous feat on the XRTT750 – already considered an out-of-date machine. With its iron cylinder head motor that changed soon after for alloy – when he competed in the Trans-Atlantic Match Races in England in 1972. This competition pitted the best British riders against the top American road racers. With no experience on British race tracks, he won three out of the six races at meetings held at Brands Hatch, Mallory Park and Oulton Park. Like the XR750 dirt tracker, the XRTT had Ceriani forks up front, twin Girling shocks on the rear, and twin 36 mm Mikuni carburetors along with a tuned (dual reverse cone) exhaust swooping down one side. Unlike the dirt tracker though, it came with brakes: a rear disc brake and in front, a twin-leading- shoe drum brake. The XRTT was the last competition bike to compete with drum brakes – they were soon to be superseded by disc brakes on all other racing machines. Top speed was 145 mph clocked at Daytona in 1970. The official horsepower for the bike has never been published, but estimates for the early 1972 engines that were in the high 70–79 hp (52–59 kW) range.
These days they are claimed to be increasing to an estimated 100 hp (75 kW), but just over 90hp is said to be a little more realistic. Still, not bad for a bike that refuses to have a sell by date. The XR750’s successful reign as a competitive machine had customers demanding a road legal version and the XR1000 Sportster. The Sportster used the same alloy heads as the XR750 which was born around 13 years after the first XR750 was built.
So what about the flying bit you ask? Famous showman, stuntman and well known Hell-raiser, Evel Knievel used the XR750 on his many successful and unsuccessful attempts, to leap over lines of trucks, cars and buses. His most famous and possibly his most disastrous (unluckily clipping the thirteenth one), was the long jump over a line of buses at Wembley Stadium in 1975. Since 1970, Harley-Davidson have captured a record number of championship titles with the XR750. It still continues to dominate podiums today with talented factory-backed riders, like Kenny Coolbeth and Brad ‘The Bullet’ Baker, who are still adding new honours to its ever growing trophy cabinet. After all these years, it must be a big one!Seven times AMA Grand National Champion, Chris Carr, explains Flat Track: