One was a doctor from Siberia, the other an American general now running for president, and best known in Russia for his brinkmanship in Kosovo.

But now the fortunes of Alexander Pyntikov and former NATO commander General Wesley Clark -- who last week created a political sensation by declaring his candidacy for U.S. president -- are entwined in a company that makes push bikes.

But these are no ordinary push bikes: The U.S. Special Forces Command currently freewheels on them, as do police in Clark's native Little Rock, Arkansas.

The bikes can go up to 48 kilometers per hour, running on an electric motor designed by Pyntikov. The makers claim the bike's design does away with controlling speed by brakes or gears.

"You don't need brakes, transmission," Pyntikov said in a telephone interview from Dulles, Virginia. "It can simply fly."

Pyntikov, who moved to the United States in 1997, invented a motor that uses computer algorithms to maximize torque and efficiency, together with another Russian scientist, Boris Maslov.

General Clark came on board in April as the new head of the company building the motor, WaveCrest Laboratories. He is aggressively lobbying for the bikes to be taken up by the U.S. military.

"The military always needs transportation for its men, but there are a lot of places, like tight alleys in urban areas, where you don't want to be in a Humvee, which is big and noisy," Clark said in an interview with The New York Times. "You just turn the handle and it just scoots. There's no sound. Just acceleration and speed. Just a swoosh on the pavement."

The Special Forces Command is trying out a half-dozen prototypes of the folding-frame bikes, powered by two 36-volt batteries, the Times reported.

Historically, armies have used bicycles in one form or another, but not in recent battles. The Swiss army operated bicycle patrols until late in the 1990s.

Bicycles were first used in wartime in 1898, when the U.S. military deployed troops on bikes to help with crowd control in Cuba. A bicycling corps was set up by South African forces to scout for information on British troop movements in the Boer War.

Clark, who was awarded a Silver Star and Purple Heart for heroics in the Vietnam War, saw the Vietcong use bicycles to carry supplies down the Ho Chi Minh Trail.

The highly experienced, but unpredictable Clark hit the headlines in 1999 by ordering the seizure of Kosovo Airport from a Russian battalion. A British general subordinate to him, Lieutenant General Michael Jackson, refused to carry out the order, famously telling Clark: "Sir, I'm not starting World War III for you."

The four-star general's surprise decision last week to seek the Democratic nomination to challenge U.S. President George W. Bush next year is his latest unorthodox move. So far, Clark is riding high in his first foray on the campaign trail, with one poll giving him an early lead among Democrat voters, and another putting him trailing the president just 47-43.

But apart from high-profile support from Clark, the scientists believe the bike's innovative technology makes it a winner.

The motors use technology developed through Pyntikov's medical background. Born in Belarus, Pyntikov studied in Barnaul to become a doctor in psychiatry and medical psychology, but it was inventing that more interested him.

"All my inventions are based on the human neural system," he said.

The bike's motor uses electric pulses to activate a series of electromagnets, which then repel and attract a set of magnets making the motor spin. WaveCrest's motor uses a central processor that gives the rider finger-touch control over motorized speed. Pyntikov said that the company's mathematical model could run at 88 kilometers an hour, and do about 45 kilometers to the liter.

WaveCrest, founded by the two Russians and Allen Andersson, the technology entrepreneur, eventually hopes to move on to motors for gas and electric hybrid cars.

Pyntikov has been working on the idea for nearly 10 years. He first developed a prototype in a garage while still in the United States on a tourist visa. His visa had run out when a former Special Forces officer with connections with the U.S. Defense Department came to try out the bike. Not being used to the motor, he promptly flew 3 meters into the wall. Pyntikov had visions of being arrested and deported; instead, he found he had an $80,000 contract with the military, which helped him get a new visa as "a person of extraordinary ability."

Pyntikov had already had an interesting career. After coming to Moscow, Pyntikov says he made millions in the early 1990s through his inventions, becoming deputy chairman of the government's Innovation Board and vice president of the Russian Innovation Fund.

He left for Cyprus in 1992, forming Tross Enterprises and working in electric motor technology for the next few years. Then he left to try his luck in the United States. "I'm a crazy inventor, and I don't think Russia is a good place for that," he said. "Here you can fulfill any dream, but in Russia, it's not possible."

Pyntikov says he has more than 500 inventions, with 60 registered patents and another 160 pending. It doesn't worry him that he is linking up with the general who once put Russia's nerves on edge by ordering British troops into Kosovo Airport, which Russian troops had taken over during the war in 1999.

Pyntikov hopes to get resident status in the next two years. "My first daughter is getting married to an American. My kids only speak English," he said.

Back home, the idea of Russian scientists offering their inventions to the U.S. military is worrying to some analysts. Alexander Pikayev of the Carnegie Moscow Center said that Russia has lost many scientists in a brain drain that has seen many of the most talented go abroad, mainly to the United States, Germany and Israel.

And the brain drain has often helped other countries in the development of new military technologies. "It's a big problem," said Pikayev, saying that there was a possibility that Israel had developed sea-based missiles and improved air missile defenses through the help of Russian emigres in the 1990s.