The Commerce Commission is writing to bicycle importers and distributors nationwide requesting a voluntary recall of potentially unsafe 'retro'-style bicycles.

The Commission is currently investigating two retailers for allegedly selling bicycles which contravene safety standards.

The Commission has also met the Bicycle Industry Association which has pledged its commitment to safety and undertaken to reinforce with its members the necessity for compliance with the compulsory safety standards.

The bicycles are sold under a variety of names including 'retro', 'chopper', 'cruiser', and 'lowrider' and the Commission believes a large number may have been sold recently.

"We have found bicycles which breach the standard in some or all of the following ways: no front brakes, handlebar width exceeding allowable width, height between seat and handlebar ends exceeding allowable depth, incorrect fork geometry, no reflectors, and problems with the length of the frame causing uneven and dangerous weight distribution between front and back wheels and potential stability difficulties," said the Commission's Director of Fair Trading, Deborah Battell.

"Any one of these defects could compromise rider safety or affect handling, especially in an emergency," she said.

"Retailers and wholesalers have an absolute responsibility to ensure that any bicycle sold meets the safety standard.

"Consumers who suspect their bicycle does not meet the safety standard should immediately take the bicycle back to their retailer. Some breaches are easily fixed, but in other cases, a refund may be necessary," said Ms Battell.