If you are tired of riding a bike to work, hunched over in a fetal position, there's hope. And relief. The durable, versatile, all-purpose, user-friendly mountain bike is here.

At last, comfortable bike riding for the baby boomer.A large percentage of today's mountain bike buyers grew up riding fat-tire bicycles with fenders around the neighborhood. But somewhere on the way through high school and college, the street bike (10-speed) took over, complete with drop style handle bars and narrow tires. Riding to work or school took on the look of a jockey going down the back stretch. Casual bike riding wasn't all that casual.

Meanwhile, the upright handlebars went out of style faster than Tiny Tim. Anyone caught riding an upright was either too old or too silly.

All that began to change quickly about seven years ago when the mountain bike was developed in Marin County, Calif. The specially geared bike featured wide tires, upright handlebars, a thicker frame and a softer ride. Biking became fun again. you could ride and talk and actually see the scenery as you went by.

Today, especially in the West, mountain bikes are all the rage, accounting for over 90 percent of many bike shop sales. At Guthrie's in Salt Lake, mountain bikes made up 75 percent of sales two years ago. Last year it was 80 percent and this year over 90 percent. Virtually all the adult bike sales are mountain bikes.

"You have a more comfortable ride," said Guthrie's Derek Ness. "You have more stability and visibility than the old bikes. And you also can get a wilderness experience as well as a biking experience."

Versatility is the key to the mountain bike's appeal. It is comfortable in city riding, handling hilly areas far easier than street bikes. It can easily jump curbs or go over rough areas. It also takes the rider up mountains and over dirt roads without problems. The old 10-speed racing bikes were prone to wrecks, flat tires and damage if stress was put on them. Mountain bikes have 15 or 18 gears that are set to handle hilly terrains much better than racing bikes.

The way sales are going, there's no end in sight to the appeal of the mountain bike. Bill Groff of Rim Cyclery in Moab says road bikes are not selling while mountain bikes are booming. "I have no road bikes even in stock and nobody has wanted any for two years," said Groff. "The bicycle business here is 99 percent mountain bikes nowadays." Added Brock Selig of White Pine Touring in Park City, "A lot of folks grew up riding a balloon tire. They don't intent to ride to work hunched over on a bike with skinny tires." Selig said this year over 200 mountain bikes have been sold in his store and just two road bikes.

Not that the mountain bike is for the sedentary. Races are held all summer throughout the West. Last weekend about 150 participants met to race near Park City for cash prizes. In Moab, the annual Halloween week Fat Tire Bike Festival is going strong, having expanded in just four years from a group of about a dozen riders to over 500 riders. The various trails range from novice to expert.

Shop owners are obviously pleased with the mountain bike's success, but are also expecting a revival in the street bike market in a few years. They say mountain bike buyers are getting in shape and become hooked on the sport. Eventually they buy a street bike for distance riding and conditioning.

"A lot of them will end up owning two bikes," said Selig.

Utah is one of the best mountain biking areas in the country. The Wasatch Front has numerous scenic trails and the Moab area boasts some of the most popular mountain biking areas in the country (see chart).

However, if you're planning on buying a mountain bike for everyone in your family, start saving. Prices range from about $300 to over $1,000 per bike. If you are only an occasional rider, bike rentals are available at several area bike and touring shops. The charge is about $10 for a half day or $15 per day.

"For most people," said Ness of Guthrie's, "the mountain bike just makes sense. Unless you are racing there isn't much sense in buying a road bike."

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ADDITIONAL INFORMATION

Mountain bike trails

Here are several popular Utah mountain bike trails.

- North Canyon-Mueller Park. This ride outside Bountiful is 16 miles. It is easy enough for novice riders.

- Ridge Ride or Desolation Trail: Between Big Cottonwood Canyon and Park City. Ride is seven to 17 miles, depending on the route taken. Easy enough for novice riders.

- Uintah mountains: Various routes are available. Trail maps can be obtained through the Forest Service, and are often the same as ATV trails.

- Slickrock Trail: One of the state's most famous rides near Moab. It's not for beginners and is considered a moderately difficult ride. A 12 mile loop.

- Hurrah Pass: Also near Moab. Runs along the Colorado River. Includes scenic cliffs and Anasazi petroglyphs. Ride is 30 miles and can be managed by a novice rider.