They can buy normal bikes and have them set up so that they come apart, or people can buy special bikes that are designed to fold for travel.

Bike Friday, manufactured in Eugene, Ore., is probably the most highly regarded folding bicycle for serious recreational uses such as long tours and century riding.

The Bike Friday bicycles, which range from $1,095 to $3,495, are designed to fold into their own carrying cases. The carrying case can be converted into a travel trailer that can be pulled behind the bicycle.

Cycling travel resources For more information on products: Rex Cycles: (916) 446-5706, www.rexcycles.com S and S Machine: (916) 771-0235, www.sandsmachine.com Bike Friday: (800) 777-0258, www.bikefriday.com Brompton Bike USA: (800) 783-3447, www.bromptonbike.com Bike Pro: (800) 338-7581, www.bikeprousa.com For support and general information: League of American Bicyclists: (202) 822-1333, www.bikeleague.org

The Brompton folding bike from Great Britain has a clever design and is upright, meant for more utilitarian riding around town.

Ultimately, though, miniature or folding bikes don't ride like real bikes. They're compromises.

S and S Machine in Roseville makes the S and S Bicycle Torque Coupling, a way to have your bike and fold it, too. The couplers are sold to bike manufacturers and frame builders, allowing a standard bike to be taken apart but still to roll like a normal two-wheeler.

Six years ago, S and S owner Steve Smilanick wanted to take his bike on a cruise but needed it to be smaller because of baggage limits, so the frame had to be cut. Then, so he could put the bike together, steel couplers were added.

Smilanick found that the system worked perfectly and decided to go commercial with it, calling it the BTC (bicycle torque coupling).

The couplings, which lock and unlock with a simple wrench that is included in the package, can be included in the building of a new bike or be added to an existing steel bike.

S and S also manufactures travel boxes designed to hold full bikes and still be within airlines' regulation size for standard baggage. In other words, no surcharge.

S and S even sells a special nylon-covered foam padding for the bike frame that takes up less space than pipe insulation, letting cyclists fit more bike parts, souvenir jerseys, hats, shorts and socks.

The business has increased by 50 to 100 percent each year but still amounts to only 5 percent of the company's business, which consists mainly of the machining of medical and other precision parts.

Tandems are still the largest portion of bikes using the coupling system, according to Smilanick.

"The tandem market really took to this system," he said. "But most tandem owners, once they realize that they don't have to compromise to travel with their bikes, have their single bikes retrofitted."

Sacramento frame builder Steve Rex was the first to build commercial bikes using BTCs.

"It's a beautiful system," Rex said. "The coupling is well-made, the boxes are well-made, and it all works together well."

He should know. He and his wife used an S and S coupled tandem frame this summer for the 750-mile Paris-to-Brest-to-Paris trek.

Sacramento health lobbyist Michael Hawkins anticipates having the coupling system, which costs approximately $325 including parts and labor, retrofitted to his bike.