Government policy that discourages cycling in Hong Kong is also keeping bicycles off public transport, cyclists say.
Train and bus operators accept bicycles but impose strict size limits and while most ferry companies allow bikes on board, some charge an extra fee.
On the MTR, a bike is treated as "bulky luggage". Its total dimensions - length plus width plus height - cannot exceed 170cm and it must be folded or have its wheels removed.
On buses, the maximum volume is 0.1 cubic metre, which is sufficient space for only one type of folding bicycle. Kowloon Motor Bus says bicycles should also be "properly packed", while New World First Bus and Citybus say they should be "packed with a bag".
Hong Kong Cycling Alliance chairman Martin Turner said the grudging attitude towards bicycles on public transport stemmed from the government's policy of discouraging urban cycling.
He said the wheels-off rule was absurd, and doubted the need for putting a bicycle into a bag.
"A bike with both wheels attached and brake working is safe and manoeuvrable," he said. "It's not dangerous. It's just a little thing that goes into the corner."
He suggested that bus companies fit bike racks to the front of their vehicles, as is done in San Francisco.
Neo Democrats lawmaker Gary Fan Kwok-wai, deputy chairman of the Legislative Council's transport panel, said the MTR could start to be more bike-friendly by assigning space for cyclists and their bikes.
"More could be done when demand goes up further," he said.
Southern district councillor Paul Zimmerman, chief executive of non-profit organisation Designing Hong Kong, said government policy on bicycles was largely to blame for public transport operators not being more accommodating.
"The MTR is not going to spend money without a change of transport policy," he said.
Democratic lawmaker Wu Chi-wai, however, said he understood that crowding on public transport made it difficult to accommodate more bikes.
The Transport Department said it encouraged public transport operators to allow the carriage of bikes "on the condition that safety and passenger convenience would not be compromised".
MTR Corp said its trains were busy and that it relied on passengers' co-operation to ensure journeys were safe and comfortable.
Bus firms said they needed to strike a balance between convenience for cyclists and overall safety inside buses.
Cyclists have also urged the government to review its policy on bicycle parking spaces, saying seizures of bicycles have been carried out by officials for years, with no acknowledgement that bikes have been parked illegally.