New research supported by UK cyclists' organisation CTC suggests that motorists give cyclists in cycle lanes less room than those riding on roads without lanes.
Using a bicycle with instruments that measure the distance of passing vehicles, Ciaran Meyers from the University of Leeds' Institute for Transport Studies studied three roads, each with and without cycle lanes on certain sections.
Meyers said his analysis showed that "significantly wider" passing distances were adopted by motorists on roads without cycle lanes when speed limits of 40-50mph were in force.
On a 9.5m-wide carriageway without a 1.45m-wide cycle lane the extra passing distances were 181mm (50mph) and 68mm (40mph) – enough to be deemed statistically significant.
When the speed limit reduced to 30mph, the extra passing distance where a cycle lane was not present was 37mm – not statistically significant.
All the cycle lanes were slightly narrower than the minimum width of 1.5m (5ft) recommended by the Department for Transport. The majority of Britain’s cycle lanes do not comply with this guideline.
According to the research, when there is a cycle lane motorists drive within their own marked lane with less recognition of the need to provide a safe and comfortable passing distance to those using the cycle lane. The study concludes that “cycle lanes do not appear to provide greater space for cyclists in all conditions”.
John Parkin of the University of Bolton, who was also involved in the study, said: “In the presence of a cycle lane, a driver is likely to drive between the cycle lane line and the centre line in a position which is appropriate for the visible highway horizontal geometry ahead of the driver.
"A cyclist within a cycle lane does not seem to cause a driver to adopt a different position in his or her lane. This has important implications for the width of cycle lanes and implies that their width should never be compromised.”
CTC say they support the government's advice on the matter, which is that attempts should be made to reduce traffic volume and speed before considering implementing cycle lanes or, as a last resort, off-carriageway cycle tracks.
One possible solution to the problem of close overtaking of cyclists not mentioned by the CTC is simply to press for a national law in the French style – where motor vehicles must give at least 1m of space when overtaking a cyclist in a built up area and 1.5m elsewhere.