Trek Bicycles is recalling some models of 2013 Madone bike because of problems with the front brake.

The recall involves model year 2013 Trek Madone bicycles with model numbers 5.2, 5.9, 6.2, 6.5, 7.7 or 7.9, and serial numbers starting with WTU and ending with G or H. A list of all serial numbers included in the recall is at Trek's website.

Trek’s UK media maven Chris Garrison told us that UK riders who had affected Madones “should take it into a retailer for inspection. If it's got the problem bolt, we will replace the brake for them.”

Chris added that Trek UK had already sent out notices to customers that they knew had purchased this bike via a Trek retailer.

If you have one of the affected bikes, you should stop riding it immediately. The problem affects the front brake cable clamp bolt on the brake quick-release, which could come loose. This could allow the cable clamp to detach and potentially result in the loss of use of the front brake.

Trek has received five reports of loose bolts.

Some of the recalled models are custom-ordered Project One Madones. The model number is printed on the bicycle frame. The serial number is printed on a sticker underneath the frame of the bicycle. The bicycles were sold in a variety of colors.