Entrepreneur Tom Nardone and the volunteer group known as The Mower Gang discovered the remains of the Dorais Park Velodrome at Outer Drive and Mound in Detroit while cleaning up a park last fall.

It was hidden beneath two decades of overgrown weeds, trash and a lot of tires.

After clearing the brush and hauling away the garbage at the track, entrepreneur Andrew Didorosi and Ben Wojdyla, associate automotive editor of Popular Mechanics, got started on a project to restore the concrete track. Didorosi said the two undertook the restoration "just to do it," but it was "no small amount of work."

"About two or three days into the restoration we said, "What if we had a race? Wouldn't that be funny?' " he said. "It just kind of spiraled into this whole official thing."

Now the duo is preparing to host the third Thunderdrome event of 2011 at the Dorais velodrome. The event attracts wheeled racers of all kinds, ranging from mo-peds to mountain bikes to Go Karts.

Didorosi is not only the president and CEO of, he also holds those titles withand. His many ventures earned him a spot as a 2011 honoree for Crain's 20 in their 20s.

There were 120 racers and more than 900 spectators at the inaugural Thunderdrome.

This year, Thunderdrome went on the road in June with a second event in Kalamazoo, a move that Didorosi was not sure would be fruitful.

"We were afraid of going outside Detroit, but we had a following (in Kalamazoo) too," he said. "It's funny how the Internet works and you think it's local and only your friends of friends are trading links, but it grew very quickly."

The first velodrome race this year was in April and the second is Sept. 10.

The event is free for spectators, and Didorosi said that will always be the case. Riders will pay a $20 entry fee online or $25 at the event, but waiting is not advised.

Organizers are expecting more than 150 racers. Didorosi said he has been thrilled with the enthusiasm for the race.

Thunderdrome is a nonprofit organization. Didorosi said that the cost of putting on the event will warrant a cap to the number of participants.

Sponsors of the event include; Nardone is president and CEO of the company. See www.thunderdrome.com for more information.