Bicycling Street Smarts
4 - GETTING ACROSS NON-STANDARD INTERSECTIONS
Not all intersections are of the standard, "crossroads" type. Though the same principles of lane positioning apply to all intersection maneuvers, some situations can be confusing and deserve a second look.
ENTERING THE ROAD
Bicyclists sometimes will ride against traffic or take unusual routes across intersections to get to their lane positions. Don't do it!
Instead, look for a good place to enter, where you can start out with a normal intersection maneuver: a left or right turn, or a lane change to merge into traffic. The traffic laws apply as soon as you're on the road, and even if you have to walk your bike a short distance to a driveway, a legal start is much safer. Besides, you often get started faster, since you can then move with the normal flow of traffic.
When entering the road from a narrow driveway, ride down its middle. A pedestrian could be approaching on the sidewalk from either side, and a car could be about to enter the driveway from either direction. By placing yourself in the middle, you can see in both directions equally well.
When entering the road, look left, but always look right as well for pedestrians and overtaking cars.
Even when preparing for a right turn onto a rural highway, look left, right, left, and then right again. A car approaching from your right can pull out to pass very quickly and head for you in the lane you're about to enter.
Traffic follows the usual rules at a diagonal intersection, but it's harder for drivers to look into the diagonal cross street behind them. Be especially careful of vans and trucks, which have a right rear blindspot.
Some of the turns in a diagonal intersection aren't very sharp, so cars may not slow down very much. Be alert to oncoming left-turning traffic, and be sure the drivers have seen you.
ON- AND OFF-RAMPS
When you're riding along a road and an on-ramp comes in from the right, stay in your normal lane position. Traffic from behind you on the ramp will first pass to your right, and then to your left.
If passing an on ramp or off ramp as in (a), ride in a straight line. Enter or exit by following the right side of the ramp as in (b). If a combined roadway is short, keep your position as in (c), avoiding the need to merge right and then left again. You may avoid having to merge across a lane by riding the left side of a ramp as in (d), but then move into your normal lane position when traffic allows.
An off-ramp is much like a right-turn lane, except that the traffic is faster. If you're going straight and the ramp goes off to the right, stay in your normal traffic position, to its left. The exiting traffic will pass you on your right, and the through traffic will pass you on your left.
When you're passing an off-ramp, exiting drivers may hesitate to pass you on the right. It's effective to stay a little farther to the left than usual and make a left-turn signal. Drivers can see your hand signal for hundreds of feet behind you, so it's useful even when cars are traveling at highway speed.
A one-way roadway can have on- and off-ramps to the left side. When entering on a ramp from the left, ride along its left side, then the left side of the roadway until you can merge across to your normal lane position. When exiting on a ramp to the left, cross to the left before the ramp and ride on the left side of the ramp until it is safe to move to your normal lane position.
Sometimes two roadways will join or divide, but the total number of lanes will stay the same: For example, a couple of one-lane roads can join into a single two-lane one-way road. In high-speed traffic, it's best to ride near the edge, as with ramps. When entering or exiting from the left in slower traffic, you may ride on the right side of the left road, so you avoid having to cross as many lanes.
A modern roundabout is a circular intersection that may have one, two, or even three lanes. All traffic turns right when entering or exiting. Entering vehicles must yield to those already in the roundabout. Modern roundabouts usually reduce vehicle speeds and have lower crash severity than conventional intersections. However, bicyclists should be cautious, as drivers may be new to roundabouts and may not anticipate bicyclists in them.
In a modern roundabout, keep right if you're going to turn right at the first exit. But if you're going past it, move toward the inside as you enter. Merge back to the outside as you approach your exit. Look back, signal, get a driver's cooperation and yield to traffic as needed before changing lane position. Avoid crossing entrances and exits when at the right, as entering and exiting drivers may not see you. When you do move right, be alert for entering vehicles. Stay clear of large vehicles needing more space.
Modern Roundabout: Keep right (a) to take the first exit. Merge toward the left (b) if you are going past the first exit, and to the inside lane if you are going to make a left turn (c) or U-turn.   [Graphic adapted with permission from Arizona DOT]
If you are not comfortable riding through a modern roundabout, dismount before the roundabout's splitter island and walk your bicycle around the outside, following pedestrian rules.
TWO LEFT TURNS IN A ROW
Sometimes you need to make two left turns quickly, one after the other; for example, if you're turning left at an intersection and then turning left into a driveway at the middle of the block.
In this case, don't head for the right side of the street after the first left turn. You may not have time to change lanes to the left again. Finish your first left turn in the correct lane to begin your second left turn.
LEFT TURNS ON ONE-WAY STREETS
If a one-way street is two or more lanes wide, laws in most places allow you to ride at either side. When you make a left turn from a one-way street onto another one-way street, it's easiest and safest to ride around the corner on the left.
BIKE LANES AT INTERSECTIONS
Bike lanes give bicyclists a narrow lane to the right of motorists. Sometimes you must ride outside the bike lane to be safe, especially at intersections. Pass slower vehicles on the left. If you pass on the right, the vehicle you are passing might turn right without the driver ever seeing you, and that vehicle also hides you from oncoming drivers who might turn left in front of you.
Bike lane right turn problems. Straight-through bicyclist must cross paths with right-turning traffic. Motorist (a) must look left and ahead for other traffic and may not see the bicyclist. If motorist (a) does yield to bicyclist, left-turning motorist (b), who can not see the bicyclist, may proceed into path of the bicyclist, and motorist (c) must wait. The bicyclist, not sure if motorists (a) and (c) are turning, must look both backward and forward.
The bicyclist has merged out of the bike lane in advance of the intersection. Now nobody has to look backward and forward at the same time. Motorist (a) can make a safe and legal right turn. The bicyclist and motorist (c) can both continue through the intersection. Motorist (b) can see the bicyclist and knows to yield. Dashing of bike lane stripe indicates to right-turning motorists that they should merge right.
When turning left, merge left before the intersection as described earlier in this booklet. When going straight through, don't let right-turning traffic get on your left and "hook" you. Unless the bike lane goes to the left of a right turn lane, this means moving left (out of the bike lane) before the intersection, merging into line with the cars. When turning right you can usually stay in the bike lane.
Some motorists may think that the bike lane is "your space" and you should stay in it. Your safety is more important. Bike lane or not, follow the lane positioning guidelines in this booklet.
And there they are - the difficult intersection types. Once you can handle these, you can ride just about anywhere. You can even figure out how to handle intersections not described here by using the principles of lane changing and positioning on which all intersection maneuvers are based.