Should you “take the lane” – ride in the centre of the road lane – or ride on the left hand side of the lane? The Road Code says “you should keep left, but not to the extent that it compromises your safety” for example by riding in the door zone of parked cars. The Code says you should take the lane when approaching a roundabout or intersection, and that it’s acceptable to take the lane when the road is narrow, there are parked cars, or if you’re turning left at an intersection (to avoid being cut off by another vehicle turning left). But we’re sometimes reluctant to take the lane, because we feel we’re holding up following vehicles.
In fact, taking the lane often doesn’t make any difference. I recently came across a good diagram (from the UK, which is why there’s the odd mixture of metric distances and imperial speeds) that explains why.
To pass safely, the Road Code says a car needs to be 1.5m to the right of a bike, which is about 0.7m wide. Most cars are about 1.8m wide. So overtaking requires at least 0.7+1.5+1.8=4m of road space. But most urban lanes are less than 4m, so a passing vehicle almost always needs to go into the next lane over, meaning that it doesn’t matter if the bike is at the edge of the road, or taking the lane.
The diagram also makes the point that riding single file doesn’t necessarily make it easier for vehicles to pass a group. But if you are riding in a group, it is polite to be considerate of following drivers.
Taking the lane is a powerful way of ensuring your visibility and safety. As a rule of thumb, if you’re being passed too close, you should take the lane next time you’re on that piece of road.
Does taking the lane hold up cars? Yes, but generally no more than if you rode on the left hand edge, and the delay is usually less than that caused by the queue at the next intersection. And if bikes taking the lane is causing problems for traffic, there’s often a simple solution – put in a cycle lane.