LEADVILLE, Colo. (AP) -- Lance Armstrong can't remember the last time he raced 65 miles by himself.
"I don't know, maybe when I was a young, young kid," he said. "You would never do that on the Tour, so none of the Tours I won.
"Quite literally in those Tours, excluding time trials, I probably rode alone for 20 miles. ... It's been a long time since I was time trialing for that long."
So strong was Armstrong on Saturday that he left the rest of the field in the mud just 35 miles into the lung-searing Leadville 100 mountain bike race, winning the nation's highest-altitude endurance test in record time.
Despite racing through freezing rain at the start, which made it difficult to shift gears on the foreboding descents on a flat back tire for the final 10 miles, Armstrong shaved nearly 17 minutes off the record, winning in 6 hours, 28 minutes, 50 seconds.
He dethroned six-time defending champion Dave Wiens, who came in second in 6:57:01 a year after holding off the seven-time Tour de France champ by about two minutes.
"He's Lance Armstrong. And he's just off of the Tour," Wiens said. "Last year he was just off of the couch. That made it a pretty fair fight for he and I. This year I rode fantastic today. I'm happy.
"He killed it. He got away from Ben Sonntag and time trialed it for 65 miles."
Last year, Wiens won in a record time of 6:45:45, but that was before Armstrong began training in earnest for his return to the Tour this year.
The race featured 1,400 mostly amateur cyclists and began with snow-crested peaks as a backdrop. Armstrong and Wiens were in a pack of pro racers that broke away early, but they fell back one by one, including Tinker Juarez because of a broken seat clamp 30 miles into the race.
"Of all things, a seat clamp," Juarez said. "I was just beginning to get my confidence up. I couldn't believe what happened. How could something that simple take me out?
"I was ready for this. I felt I was ready to hang it all out with these guys."
Nobody could keep up with Armstrong, who found himself all alone well before he even climbed to the Columbine Mine turnaround that sits atop a peak halfway through the 50-mile out-and-back course that winds its way through the Rockies and features lung-burning climbs and technical descents.
On his way back down, he saw Wiens struggling in second place.
Armstrong, who said he was somehow more nervous for this race than he ever was for the Tour, would rather have had company on his way back to the tiny mining town of Leadville that sits at 10,152 feet.
"I sort of had to decide what to do, if you wait for the other guys or if you just try to go the rest of the race by yourself," Armstrong said. "And it's a little risky to do that. At the end you're wasted. Buy I rolled the dice a little bit. Plus, I was freezing. I wanted to start riding hard because I was about to freeze."
Armstrong was so spent at the end that he wolfed down as many candy bars and sodas that his handlers could round up.
"I felt better than last year. Obviously, I'm more prepared than I was last year, but that cold start was brutal," Armstrong said. "The dirt was nice and tacky, so that helped. You could ride Powerline (where the rest of the field always walk their bikes up the gravel trail) pretty easily. So, no complaints."
Except for his flat tire.
Armstrong was so safely in front of Wiens that he didn't worry when he heard a hissing in his back tire while coming down the last descent toward the finish.
Armstrong may be the best human on two wheels, but when one of them breaks, he's as useless as a motorist scratching his head as he peers under the hood.
So, he put some air in his tire and hoped for the best.
"I don't normally change flats. I call the car and they fix it. That's the way it works in road cycling," Armstrong said. "And when I'm out on a ride and have to change one, I'm just terrible at changing flats. So, that's why I just put more air in it, thinking that the foam would seal it.
"And it did for a while and then I just said, 'Ah, screw it, I'll just ride it home."'
For the last mile or so, the back tire was completely squishy and he fishtailed across the finish line.
"This is a special race, the dynamic of going out and back and so I see everybody else in the race," Armstrong said. "I mean, I see everybody from Dave, I see where he is, and then I see the last guy who's not going to make it."
Some of them had their heads down and Armstrong figures he narrowly avoided four head-on collisions with amateur riders who had no clue he was heading straight for them on the back 50.
Armstrong's next road race is the Tour of Ireland next week.
He said he'll return next year to defend his Leadville 100 title, but Wiens, who at 44 is seven years older than Armstrong, said he might just call it a career.