Three Feet, and Why Riders Sit Where They Do

Riding weather here is every month of the year, so cyclists are a permanent part of the traffic rather than a summer feature — commuters on surface streets, groups on the coast road at dawn, and riders grinding up the canyons on weekend mornings. The interactions that go badly are a short list, and almost all of them are about position and turning rather than speed.

The passing rule, and what it measures

California's Three Feet for Safety Act, Vehicle Code section 21760, requires a driver overtaking a bicycle traveling in the same direction to leave at least three feet between any part of the vehicle and any part of the bicycle or the rider. If traffic or road conditions make three feet impossible, the law does not give you permission to squeeze past — it requires you to slow to a reasonable and prudent speed and pass only when it can be done without danger.

Read that measurement carefully. It is not three feet from your tire to the bike; it is three feet from any part of your vehicle, mirrors included, to any part of the rider, elbows included. On a road where you are doing thirty miles an hour more than they are, three feet is a legal floor and a poor target. Change lanes to pass when the next lane is clear.

If you have to think about whether you have room, you do not have room. Wait ten seconds.

Why the rider is not hugging the curb

This is the source of most driver frustration, and it is worth understanding because the rider is usually making a deliberate safety decision. Vehicle Code section 21202 asks riders to keep as near to the right-hand edge as practicable, and then lists the situations where they do not have to: passing, turning left, avoiding hazards, and — the one that matters most here — when the lane is too narrow for a bicycle and a vehicle to travel safely side by side.

• The door zone. A parked car's door swings roughly the width of the door into the roadway, and it opens without warning. Riders stay out of that band on purpose.
• Surface debris. The gutter is where glass, gravel, sand and drain grates collect, and a narrow tire finds all of it.
• Being seen. A rider further out is visible sooner to a driver pulling out of a driveway or side street, which is where a lot of collisions start.
• Preventing an unsafe pass. A rider taking the middle of a narrow lane is communicating that there is not room to share this stretch.

The bike lane is a lane

Where a marked bike lane exists, Vehicle Code section 21209 keeps motor vehicles out of it except in specific cases: to park where parking is permitted, to enter or leave the roadway, and to prepare for a turn within 200 feet of an intersection. That last one surprises people, because it means the correct way to make a right turn across a bike lane is to merge into it first, after yielding — not to turn across it from the through lane at the last moment. Signal, check over your shoulder, merge, then turn.

The two turns that cause the collisions

The right hook. A driver overtakes a rider and then turns right across them. At the moment of the turn the rider is at your right rear quarter, still moving forward, in the part of the mirror nobody checks. The habit that fixes it: never overtake a bicycle immediately before turning, and look over your right shoulder before every right turn where a rider could be.

The left cross. A driver turning left across oncoming traffic misjudges an approaching rider, because a bicycle is narrow and closing speed is genuinely hard to read against a busy background. Modern e-bikes make this worse; they arrive faster than the shape suggests. If you see a rider coming and you are not certain, wait.

Opening your door

Reach across with your far hand. That single change rotates your shoulders, brings the mirror and the approaching lane into your view, and slows the door's opening — and it costs nothing. California also places the duty on the person opening the door: Vehicle Code section 22517 says you may not open a door on the traffic side unless it is reasonably safe and can be done without interfering with traffic.

If contact happens

Treat any contact with a rider as potentially serious no matter how minor the mark on your car looks — a cyclist has no structure around them, and the injury is often to the head or the shoulder rather than where the bike is bent. Stop, call for medical help rather than accepting a roadside assurance that someone is fine, and provide the information the law requires at an injury collision under Vehicle Code section 20003: your name, address, vehicle registration information and, on request, your driver's license. Photograph the road, the positions and the light.

The part drivers underestimate is what this does to a claim. A bicycle collision is a bodily injury claim rather than a fender-bender, and bodily injury is the coverage that runs out fastest on a policy carrying the state minimum. That is not a scare tactic; it is arithmetic, and it is the one thing on this page you can fix in advance.

If you have never looked at your liability limits, send us the declarations page — we will tell you plainly what they would and would not absorb, and what more would cost.