This is an excerpt from Cycling Fast.
Cycling is not classified as a contact sport, but you will likely make contact with other cyclists or their bike during races or group rides. The key to having the best chance to survive such situations is holding your line and remaining as calm as possible. The way to achieve these two survival skills is by practicing bumping and wheel touching.
In cycling terminology, this skill is called bumping, but the term leaning is a more apt name. Most cycling governing bodies frown on aggressive contact, although you will encounter it in racing. In essence, when you make contact, you want to lean into the contact. Your instincts may make you pull away from the perceived danger, but that will have poor consequences—a swerve or even a fall. Think of it this way: When you are standing in a crowded line or train or bus, if someone leans on you, you lean back. The reason you do this is to prevent yourself or the other person from falling. This is the same for cycling.
In cycling, you will encounter bumping in sprints, on corners, on narrow roads, or where either the terrain changes or cyclists around you bunch up.
Bumping Drill Caution: This drill can cause unexpected falls. Perform the drill on a well-cut, grassy field. Choose training partners whom you can trust to follow the guidelines. With their hands in the drops, two cyclists ride slowly across a grassy field, and they slowly veer toward each other to make very light contact shoulder to shoulder. The object is to just lean on each other—not push each other. Suppress the instinct to pull away suddenly. Once contact has been made a few times, try leaning on each other for extended periods. Next, try contacting the partner's thigh with your shoulder. Then try contacting the side of the partner's handlebar. Your hands need to be in the drops to avoid hooking each other's handlebars. Try all the drills on the hoods next. Watch out for hooking. Increase the speed of the drills and try to lean on your partner enough to control his or her direction of movement. A simple rule in cycling is that the person with his or her front wheel farther ahead can control the direction of two riders.
Wheel touching—one cyclist's front wheel contacting another cyclist's rear wheel—is part of bicycle racing. There are just too many people trying to fit into too few holes for an occasional wheel touch not to occur. Usually, the person in the front will not fall, because the weight of the person's body on his rear wheel prevents it. Many times the person in the back may be out of luck, because this person's front wheel is turned by the other cyclist's rear wheel. By keeping a cool head and good control, you may survive your front wheel touching. The following drill will help you in those situations.
Wheel Touching Drill Caution: This drill can cause unexpected falls. Perform the drill on a well-cut, grassy field. Choose training partners whom you can trust to follow the guidelines. With their hands in the drops, two cyclists, one in front of the other, ride slowly across a grassy field. The rear cyclist slowly veers his front wheel toward the front cyclist's rear wheel in an attempt to make light side contact, meaning the sidewall of the tires touch. Watch out for the rear derailleur. The object is to just touch tires—not push tires together roughly. The person in the front will most likely feel no contact with his rear wheel. The person in the back needs to suppress the instinct to pull away suddenly. Pulling away suddenly will turn the front wheel and cause a crash. The best strategy for the person in the back is to maintain the contact, hold the handlebars straight, and decelerate. In most cases, but not all, the person in front will naturally glide away from the front wheel, either speeding up or moving away.
Fundamental Turning Skills
As an isolated skill, turning is rarely practiced by amateur racers. Most learn as they go. This is not wise. By learning turning skills, you will be more confident in your ability to avoid obstacles, to corner, and to descend.
Turning comes in three forms: leaning, countersteering, and steering.
Leaning is the method for turning that is most often applied by cyclists. This method is suitable for wide corners in which you can see the exit. In leaning, both the bike and the cyclist are angled in the same direction. The handlebars are not turned; they are just angled with the bike and body.
To lean, approach the corner from the outside. Angle the bike toward the corner as you move from the outside to the inside through the corner and back to the outside on the exit of the corner.
Read more about Cycling Fast.