After 44 years of racing success with the iconic XR750, Harley-Davidson in entering a new era with the introduction of its new flat tracker. The XG750R is a racing-only machine developed around the Revolution X liquid-cooled V-twin engine that powers the Street 750 production model.

Harley-Davidson's XR750 is undoubtedly one of the most successful motorcycles of the recent history of American Flat Track racing. Initially introduced in 1970 as a modified Sportster, it evolved into an all-conquering flat tracker after an extensive redesign in 1972 and then proceeded to dominate the AMA Pro Flat Track Grand National Championship (GNC) for the best part of the last four decades.

The arrival of the new Street model series in 500 and 750 cc brought about a new V-twin engine. The liquid-cooled V-twin Revolution X in its larger displacement version perfectly fit the flat track racer bill, as Harley-Davidson built around it the XG750R flat tracker.

The task of converting this road-legal unit into a top-level flat track racer was undertaken by Vance & Hines Motorsports, resulting in the XG750R that will make its racing debut at the Springfield Mile in Illinois, USA, on May 29.

Technical details of the new motorcycle have not been disclosed, although we should expect a host of updates to the engine. Taking advantage of the extensive tuning leeway allowed by the AMA's rules, the performance of the XG750R will probably climb considerably higher than the 53 hp (40 kW) of the production model, while keeping the bike's weight down to the 300 lb (136 kg) minimum limit set for the GNC1 class. Obviously, the new racer shares very few, if any, parts in common with the Street 750.

The Harley-Davidson Screamin' Eagle Factory Team will start by fielding one XG750R for its rider Davis Fisher. The 18 year-old GNC1 rookie, and last year's GNC2 champion, will carry out important development work on the new motorcycle while racing it. The team's main rider and 2013 national champion, Brad Baker, will continue racing the XR750 for now.

"The XG750R has shown great potential in testing and the first few races this season," says Kris Schoonover, Harley-Davidson racing manager. "But as with any new racing motorcycle, there will be work to do. We're excited to continue testing the XG750R in real world competition, and as we make our way through the season, we will evaluate the performance of the bike and our factory riders to see if Baker might switch to the new bike."

For the time being there are no immediate plans to introduce a road-legal version of the XG750R.

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