Steven Davis embarked Aug. 26 on a 24-hour bicycle trip from San Diego to Prescott, Ariz., a distance of 310 miles, with only 20 minutes of bathroom stops.

Friends followed in a car for headlights and to hand him food as temperatures soared as high as 107 degrees F in the desert and plummeted to a decidedly chilly 56 degrees F in the mountains at night.

It was a mere warm-up by the 2003 Elizabeth Forward graduate for a much longer and grueling, albeit more scenic, excursion this month and next.

From Oct. 29 through Nov. 5, Mr. Davis, 21, a senior political science major at San Diego State University, will be one of 100 cyclists on a 640-mile journey down the coast from San Francisco to San Diego.

"Most people dream of driving it, but we get to cycle it, which is pretty cool," he said.

This first, noncompetitive event is called the Qualcomm Million Dollar Challenge as it seeks to raise $1 million for the La Jolla, Calif.-based Challenged Athletes Foundation.

The nonprofit provides funding for physically challenged people to participate in sports, using such things as artificial limb extensions and specialized equipment. Those athletes can choose to bike legs of the trip beside the 100 cyclists.

To raise $1 million, each cyclist was charged with collecting $10,000.

Mr. Davis has raised $8,000 through corporate sponsorship, individual donations and the sale of a 24-minute DVD of his 310-mile trip to Prescott.

Mr. Davis decided to get involved for the fun, the good cause, the beautiful scenery and the challenge.

He has secured permission for the time away from class.

To train, the cyclists, ranging in age from 21 to their 60s, have met for the past six months on Thursdays at the bottom of a steep hill to practice biking it. They go on 100-mile trips on Sundays.

Mr. Davis, who is coach of the university's Aztecs cycling team, also runs his own drills 18 to 25 hours a week with sprints, hill climbs and long rides. He lifts weights in the university gymnasium.

Mr. Davis grew up in Elizabeth Township, and started cycling competitively when he was 12 and living in Pinehurst, N.C.

He trained for the upcoming ride last summer with his father, Jim Davis, a former Ironman triathlon competitor, at Mr. Davis' Austin, Texas, home.

His mother, Cindy Raymond, lives in Charleroi.

For the trip, Mr. Davis will ride a rebuilt, nine-speed road bike which his father rode in his first triathlon about eight years ago.

He anticipates the third day being the hardest as it involves 114 miles of steady climbing for 13,000 feet in the Big Sur area, but which is not without its benefits.

"It's one of the most gorgeous places along the California coast," he said. Food and lodging will be provided by the event sponsors.

The ride's end Nov. 5 will coincide with the finish of the CAF's annual San Diego Triathlon Challenge.

To contribute to CAF in Steven Davis' name, send your gift to: Challenged Athletes Foundation, 3252 Holiday Court, Suite 224, La Jolla CA 92037 or visit: www.cyclemdc.com.