'06 heartbreak motivates Wheldon

The 2005 champion won the race on his way to the title two years ago, and last year he led 148 of the 200 laps, but lost a potential victory when he had to make a late pit stop due to a puncture.

"I've seen the great side of Indianapolis with winning in 2005, but I've also seen that side where, like last year, it just wrenched my heart from my body," said Wheldon, who will start sixth for this year's race.

"To be so comfortable in traffic and be so comfortable in a race car, then to pick up a flat tyre when you really can't really react from it was tough.

"It was incredibly disappointing, but it makes me very motivated to come back and try to win again."

Wheldon has made no secret of his obsession with the biggest race on the IndyCar Series calendar, and he even accepts that misfortune is also part of the event.

"In a sick kind of way, that's what makes the Indianapolis 500," he said. "That's what makes you come back.

"I led nearly 150 laps and I didn't win the race. I didn't even feature in the top three. That's part of it."