The bike is now "perfect," he said.

"The new one is made of aluminum alloy and is very stable, even when it reaches its maximum speed of 150 km per hour."

He set out to ride the funky contraption along China's border on October 28 to promote the Beijing Games.

Meng will present his bike to the International Olympic Committee after he finishes his China tour. He said he hopes to one day see it used in the Olympics.

Thinking outside the (cardboard) box

Construction worker Gao Bo works on billion-dollar projects but calls the cardboard city he has built to commemorate the Beijing Games "priceless."

"I feel a greater sense of achievement having designed my 'Olympic City,'" Gao told China Daily while towering over his 2 sqm metropolis.

"Before next year's Games I'm going to take a tour of the Olympic BMX venue and build one for my city," he added. BMX will make its Olympic debut in Beijing next August.

Gao's Olympic enthusiasm is already scaling lofty peaks.

The crane driver, who helped build the gravity-defying new CCTV headquarters in downtown Beijing, now thinks he can out-budget world-renowned designers Jacques Herzog and Pierre de Meuron, the brains behind the National Stadium, which will next summer form the centerpiece of the 2008 Games.

"With the 2.3 billion yuan ($31 million) invested in the Bird's Nest, I could have built a better stadium," said the Beijinger. "Then again it does look very nice. I like buildings with a strong visual impact."

The stadium, an interlacing latticework structure, showcases one of China's favorite dishes on a superhuman scale and is part of a new wave of visual landmarks that are collectively stamping Beijing as a city of the future.

For the 47-year-old Gao, nothing matches the new Olympic venues and the inspiration they provide.

The highly flammable but cost-efficient city that sits in his living room features a table tennis stadium shaped like a ping pong bat, a badminton stadium shaped like a shuttlecock, and a media center that resembles a flying pigeon.

His centerpiece is not a bird's nest but an ancient vessel.

"I draw inspiration from real life," he said. "I call this pictographic design."

Gao has never taken a class in architectural design. He learned what he knows from 20 years behind the wheel of a tower crane.

"While I was on the crane, hundreds of meters above the ground, I could see most of the buildings in Beijing and I took the time to study each one of them," he said.

He is currently drafting a blueprint for an outdoor diving center, inspired by the image of a peacock spreading its tail.

"The head will be the springboard, the tail the blanchers," he said.

Gao was inspired to build the Olympic City by memories of there never being enough playground space to go round as a child.

"In Beijing, there were not enough sports facilities for the public. I assume the situation may be worse in other cities across the country," Gao recalled. "So I always wanted to build some that the public could use cheaply."

Gao began to build his cardboard utopia in 1980, designing by day and drawing the blueprint by night.

It took seven years to build the racquet sport stadiums and swimming center, and another decade to do the rest.

"The vessel-shaped main stadium was dedicated to Hong Kong, as the design was perfect for a port city," Gao said. Hong Kong bid to host the Asian Games in 1997.