You're driving home from Stinson Beach, pleasantly fuzzy after a day on the sand and fun in the surf. As you pull slowly out of the parking lot, turning right onto Highway 1, ready for the drive home over the mountain, you spot three guys on road bicycles coming toward the beach exit, riding against traffic on the wrong side of the road.

No problem, you think; there's plenty of room for you to complete your right turn before the cyclists reach your position. But you misjudged a tad, and the cyclists must slow their progress a bit to let you exit the parking lot and turn onto the highway.

Then, as the cyclists pass you, riding on the wrong side of the road, one of them scowls at you through the windshield and a loud sound startles you as he smashes a fist into the side of your car as he rides past, topping off the exchange with profanity.

Road rage. But this time it's a subset. It's bike rage.

As an increasing number of people take to two-wheel transportation for commuting, errands and recreation, confrontations between bicycles and vehicles occur more frequently. Bicyclists say they constantly feel threatened and regularly encounter motorists who seem willing to drive them off the side of the road—-or worse. Motorists say they've had it with cyclists who seem to think traffic laws apply only to vehicles with four wheels.

These are interpersonal relationships at work on the public thoroughfares, and sometimes they create anxiety for those who are just onlookers waiting in traffic themselves.

Bike rage is a phenomenon that's been reported in urban areas across the country. Many motorists who have encountered what can only be called belligerent bicyclists wonder at the aggressive riding behavior exhibited by people riding a few pounds of metal among vehicles that weigh a ton or two.

And why is it that the guys (because they're mostly guys) with the scowls on their faces from exertion and the neon-colored jerseys with ersatz sponsor logos plastered on them are the worst offenders? Especially when they come careening down Mt. Tam, staking their lives that cars coming up the grade will be driving safely in the other lane as they both round a blind turn at the same time?

Wait a minute, says Marvin Zauderer. He's a Fairfax psychotherapist whose practice also includes sports psychology and executive coaching. And he's an avid bicyclist and road racer. The stereotype of the mad-crazy cyclist racing down Mt. Tam wearing phony sponsorship to pretend he's riding in a French road race may be just that, a stereotype.

To begin with, says Zauderer, one person's version of risk-taking behavior is another person's thrilling but within-bounds bike ride. And as far as thinking that all those road racers are just living out fantasies of being pros, Zauderer says there's another explanation for those jerseys with the energy-bar logos all over them: "Those who are more serious about riding road bikes, whether they compete or not, are going to ride in a kind of standard issue cycling clothing, and there are literally thousands of riders in the Bay Area who belong to teams, professional and amateur, and all those teams are sponsored. The teams typically mandate that their riders when training wear the clothing, so the sponsors get visibility."

Of course, some cyclists just like wearing the uniform, even if they're not a member of a team. They are, after all a member of a group, and they like the identity.

The feeling of group identity can be a double-edge sword. When an individual feels part of a group, individual actions can become magnified by group dynamics. And those dynamics can have drastic and dangerous consequences.

"Many people on bicycles act like the rules do not apply to them," says Leon James, the University of Hawaii professor of psychology who studies road rage and how people interact on the roads. "They believe that the rules that apply to cars, the regulations of the road, do not apply to them. That's how they act."

James says that attitude is "part of using a bicycle" in our culture. "People using bicycles are making a statement: 'I am using a bicycle, not a car. Maybe you should, too.' There's a kind of political grouping phenomenon, the bicycles versus the cars. They follow different practices."

James says the dynamics of the car/bike interaction is complicated by the belief among many cyclists that if they obey all of the traffic rules, motorists are still out to get them. "There's a recognition of a conflict of interests." The two groups, adds James, "practice a different set of rules."

While the psychological explanation for why the behavior occurs fascinates, it doesn't alleviate the tension that ensues when motorists sitting at a stoplight see a single-file of cyclists ride through an intersection without stopping. The latent hostility that starts at the intersection can bubble to boiling and result in tragic consequences when motorist meets cyclist later in the day.

During the July 4th holiday in Southern California, cyclists in the Holiday Ride, an event that draws cyclists from across the Los Angeles Area, encountered a particularly brutal example of vehicle versus bike. During a steep decent, one cyclist fell, breaking his collarbone. Two other cyclists dropped back to help the injured rider. After they proceeded on their downhill run, they were riding about 30 mph when a car came up behind them doing about 50 mph. The driver started honking. The two cyclists pulled into single file, which is appropriate behavior. The driver then pulled in front of the pair and slammed on his brakes. One of the cyclists ended up crashing though the back window of the car. Severely injured, he ended up in the hospital.

Police logged the incident as road rage and arrested the driver, who happens to be an emergency-room physician. Police handled the matter as a felony criminal assault.

That kind of aggression on the part of motorists is far from unknown to cyclists in the Bay Area, including Marin. But neither is aggression (leading from a feeling of being targeted by motorists?) on the part of cyclists.

Changing the behavior of adult cyclists who believe they are entitled to flout traffic laws is not just a tough task, says James, it may be close to impossible. The way adults ride bicycles—-and drive cars--reflects the way children are taught—-or not taught-—to interact with the wider world outside of the family.

"It starts as children, of course. When we ride as children, we don't respect the regulations; those are the habits of children. As children, we ride on the sidewalk where we're not supposed to, and we get away with it if we're children. You can see some adults engage in that kind of behavior."

Bicycle riding "in our culture simply has not been worked out yet," adds James. And as an increasing number of cyclists ride on increasingly congested roads—-for fun and for work and for errands—-the consequences of bike rage and road rage become more common. But when a cyclist gets tangled in a road rage incident with a motorist, it's the cyclist who ends up going through the rear window.

"Children have this idea of getting away with things, of saying, 'Look after me' if I bend the rules," says James. That behavior carries over into adulthood in some people. And that's the behavior exhibited in risk-taking on the road, whether it's in a car or on a bike. The best way to ameliorate inappropriate cycling behavior, adds James, is education.

Proper bicycle riding should be taught as an integral part of every child's education to make a substantive behavioral difference in a generation or two or three—-on bicycles and probably behind the wheel also. Unfortunately that kind of integrated bike-riding curriculum has been lacking in schools.

That's just the educational hole the Marin County Bicycle Coalition began filling a few years ago when it started the Safe Route to Schools program. In part, the program seeks to relieve vehicle congestion around schools, one of the biggest contributors to traffic clogging the roads during the school year.

While getting kids to ride bikes and walk to school alleviates traffic, it also provides a much-needed opportunity for exercise. Riding safely is an integral part of the program, which has spread across the country.

In Marin, the Safe Routes to School program goes into schools and offers classes as part of the physical education curriculum. In the second grade, the focus is on pedestrian safety, says program director Wendi Kallins. In the fourth grade, the program offers instruction in bicycle safety.

In addition to the classes, Safe Routes also offers assemblies, which many local schools hold. "We've also done some bike clubs, and we've done a program called Riding with Youth, where we take the parents and the kids out together, and we teach them how to safely ride together."

When kids get to middle school, Safe Routes offers information and guidance on how "to drive their bikes," adds Kallins. Those Safe Routes programs and other similar strategies are the types of programs that James says are critical to inculcate in children a sense of responsibility on the road, a responsibility he says that will extend into adulthood.

But will integrating an understanding of safety and traffic laws in young cyclists, as James mentions, stand up against the onslaught of a me-me individualist culture in which risk-taking is held up as a laudable goal? And what's the real reason behind cyclists blasting through intersections, despite clear-cut traffic laws?

"Because we haven't been able to tap into the psychology of this yet, we, too, are mystified," says Kim Baenisch, MCBC's executive director. "We have been communicating the message about how everyone needs to behave safely and courteously. We are continually surprised that we continue to hear about numerous incidents from both sides, drivers and cyclists, having issues creating and experiencing dangerous situations."

MCBC, which currently is seeking funds to study psychological factors related to bicycle riding, offers a basic street skills and safety class for adults that more riders seem to be taking, some of them not voluntarily. If a cyclist gets ticketed for a traffic violation (yes, it does happen), he or she can get a reduced fine by taking the class.

"Since we've been offering that option," says Baenisch, "the percentage of participants in our classes coming because they've received a ticket has grown to over 50 percent on a regular basis."

Every individual, motorist and bike rider, has the option to short-circuit the road-rage urge. In other words, actually in the words of Zauderer, "You have a choice." And James concurs.

The rage interaction depends on many variables: the level of anxiety among the participants, the amount of traffic, road conditions, what everyone had for breakfast. The one element most likely to break the rage dynamic is personal responsibility, say psychologists. And that goes for cyclists as well as motorists.

The critical moment, says Zauderer, is to recognize a rising level of anxiety—-before there's a chance for a possibly dangerous confrontation. The simple act of recognizing and assessing the anxiety can go a long way toward alleviating it.

"Figure out a healthy and safe way to manage the anxiety, and even at times work with the other person. The key is to see the other person not as adversary, but as partner to get through this five-second period of time safely."

You're driving down Mt. Tam, and two cyclists in front of you are riding at the speed limit. You come up behind them, slow down and watch as they ride skillfully around a sharp corner. They recognize your courtesy, and when they see it's safe for you to pass, they wave you ahead.

You both win.

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