Limestone Police Chief Stacey Mahan said William Warner, 44, of Wimauma, Fla., lost control of his modified turbocharged Suzuki Hayabusa about 4,000 feet into his run at the former Loring Air Force Base, left the track and slid an estimated 1,000 feet through the grass, the Bangor Daily News reported.
The crash occurred about 10 a.m. EDT during The Maine Event, an annual speed trial race, the newspaper said. A hospital spokesman said Warner died about 11:15 a.m.
The remainder of the day's races were canceled.
The Loring Timing Association said Warner set a world record at the time trial in 2011, becoming the first conventional motorcyclist to top 300 mph, reaching 311.945 mph on a 1 1/2-mile course. On Saturday, he broke the 1-mile record at Loring when he reached 296 mph and he was trying to hit 300 mph Sunday when he crashed.
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