Mountain bikers Alan Armstrong and Reese Vogel are blazing a trail of education and understanding.

Encounter either on a trail in the San Gabriel Mountains, and they probably will present a folding business card that reads, in bold black letters:

"There is a growing controversy over the use of mountain bicycles in the San Gabriel Mountains. Be part of the solution, not a cause of the problem."

Armstrong, a welding instructor at Pasadena City College, and Vogel, a professional photographer, are active members of the Mt. Wilson Bicycling Assn., a nonprofit volunteer organization that works with the U.S. Forest Service in an effort to preserve access to mountain trails for cyclists.

Armstrong helped form the organization in 1985 after equestrian groups proposed excluding mountain bikes from the Mt. Wilson toll road, which begins near the Eaton Canyon Nature Center in Pasadena and travels eight miles to the top of Mt. Wilson.

The dirt road, which provides access to countless trails, is a recreational corridor for as many as 45,000 pedestrians, equestrians and cyclists each year, according to Paul Downing, a deputy forester stationed at Henninger Flats, 2.7 miles from the bottom of the road.

"All of those groups are compatible if people use common sense," Downing said. "Most of the cyclists are very resonable people. But there is a small percentage that are on the wild side."

Problems have surfaced when cyclists, having been given rides up Angeles Crest Highway to the top of Mt. Wilson, use the toll road strictly for downhill racing.

"It's unfortunate that one person on a mountain bike with a devil-may-care attitude can have such a dramatic impact on other people's enjoyment of the forest," said Armstrong, who lives in Pasadena. "You have to keep educating the new people to the sport."

All of the 180 current members of the Mt. Wilson Bicycling Assn. ride mountain bikes, but theirs is not a traditional riding club.

Riding, in fact, takes a back seat to working on multiuse trails. During weekend outings, members trim the brush, clear rocks and repair water damage. The work has included hauling sandbags, logs and railroad ties through the mountains to support the trails.

"It's rewarding, and you get a better appreciation for the environment," said Vogel, who lives in Pasadena. "It actually makes you a better rider because you're more aware of what goes on on the trails."