Not having a comprehensive insurance policy could prove costly, cyclists have been warned by the Association of British Insurers (ABI).
It says those hurt in an accident, or found responsible for causing one, may face bills of thousands of pounds.
Cycle use is now around 20% higher than it was in the late 1990s.
However, the Motor Insurers' Bureau, funded by the insurance industry, provides compensation to victims of uninsured drivers, including cyclists.
Department for Transport figures show accidents involving cyclists rose by 12% in the first half of 2011 compared with the same period a year earlier.
Pepe Tozzo ended up in hospital after colliding with a car while cycling home from work in South Wales.
He recalls how he collided with the side of a van that emerged from a side road, as he was riding down a hill.
The driver of the vehicle involved in the collision had no insurance or driving licence. With no personal injury or legal cover, the costs for Pepe were soon spiralling out of control.
He recalls spending a week in hospital, three months off work, and a year recuperating to get his leg back to normal.
"There has been a long lasting legacy," he says.
"It probably knocked my career back by one year."
It is not compulsory for cyclists to have insurance. Cycle use in the UK has been increasing in recent years, up about 20% compared with the late 1990s.
With the number of accidents also rising, Malcolm Tarling, of the ABI, says there is now a strong case for all cyclists to have personal injury and third-party cover.
"If you are a cyclist and you are involved in an accident the chance of you being injured are quite high," he says.
"Some 230 cyclists a month are killed or seriously injured on the roads so there is a good chance you are going to be off work for weeks, if not months, so some sort of insurance to cover you for loss of income makes sense."
He says cyclists often underestimate the risks they face when they are on the roads, in particular if they are in an accident where they are found to be at fault themselves.
"If you are a cyclist and you are involved in an accident and you are at fault for causing it you could be sued for damages," he says.
This could amount to hundreds or thousands of pounds, he claims.
"If you are cyclist you should always have some form of liability insurance. It is essential."
However, many cyclists do not have comprehensive cover.
Tom Bogdanowicz, from the London Cycling Campaign, says many think they are fully covered by their household contents policies but these do not always go far enough.
"Household insurance policies are general insurance. They do not provide specialist cover that you might need whether it's for theft or for third party," he says.
"So if you go to a specialist insurer or to a cycling organisation to get that sort of cover specifically aimed at cycling, that is what the policy is designed for and you benefit from that."
Although cyclists may be more vulnerable on the roads, statistically they are less likely to be responsible for an accident than a motorist - and that is reflected in the premiums.
A specialist policy can cost £30 to £40 a year. This typically provides third-party or public liability cover - the costs of causing accidents to other road-users and their property.
It also usually covers damage to the bicycle following an accident and the cost of a replacement bicycle if it is stolen or damaged.