"[Dont'] pick fights with motorists, even (especially) if they’re itching for one," writes one website devoted to San Francisco's Critical Mass, the monthly bike ride that takes place in hundreds of cities around the world but has no leadership or organizing body.

But the authors of the sfcriticalmass.org site advise riders to "remember that pleasure and friendliness are more subversive than anger and blaming." A self-policing community, the site counsels riders to "tell other Massers what you think of their behavior, whether good or bad. Talk to each other!"

But apparently violating that dictum and others — such as '[don't] ride into oncoming traffic on the wrong side of the road — on Friday's group ride one cyclist ended up doing just that in the Marina District.

The above YouTube video titled "Road Rage Cyclist Breaks Car Window with U-Lock," was flagged by Redditors and posted by the Chronicle. At around 20 seconds in, cyclists move into opposing traffic. One blocks a Zipcar, staring it down as if to dare it to proceed. This, I'm told, is a maneuver frequently used to keep cars from proceeding towards other cyclists to ensure their safety. But in this case, that car, inching closer, eventually collides with the bike.

"You fucking hit my bike!" shouts the cyclist in confronting the Zipcar driver. After some back-and-forth, the driver begins to (illegally) flee the (admittedly scary) scene of the initial accident. At 1:40 or so, the driver or perhaps a passenger yells that the cyclist is a "psycho."

As the Zipcar passes by, the cyclist uses his U-lock to smash at it, attempting (but failing) to break the driver's side window.

A photo posted by Carter (@1carterart) on


"Holy shit that's infuriating," reads the Reddit thread's top comment. "Fuck these people — they clearly were riding against traffic, causing problems, and then that one guy stops in front of the zip car to purposely start problems. Bikes are supposed to be treated like cars on the road. This guy should go to jail for using that bike lock as a weapon."

Another Redditor urges the public not to consider the video's actions representative. "Please don't think these dickheads represent the community," they posted. "It'd be like saying that the drivers who regularly do sideshows/donuts in the intersections of 24th represent normal drivers."

In the 2013 words of SF Weekly, Critical Mass is an "anarchic, ostensibly leaderless movement" that served as a "battering ram."

But, on its website's guidelines, the loose organization encourages riders to "remember that pleasure and friendliness are more subversive than anger and blaming." A self-policing community, the site counsels riders to "tell other Massers what you think of their behavior, whether good or bad. Talk to each other!"

In that spirit, though no "organizational" comment is possible, SFist has contacted members of Critical Mass and await comments on the incident.

SFist has also contacted SFPD, who write that "nothing that has been reported to SFPD so far" and are looking into the matter.

Supervisor Farrell has released the following statement:

Violence is and will never be acceptable here in San Francisco. The actions by the cyclists caught on video this past Friday evening participating in Critical Mass are disturbing and should never be tolerated in our City - especially the one cyclist seen attacking the vehicle with a bicycle lock repeated times. I understand the history that Critical Mass has in San Francisco as a protest movement, and respect that a majority of the participants are peaceful and respectful of others while participating. But, the participants in Critical Mass must understand that actions like the ones this past Friday reflect poorly on the entire group and hurt the group’s overall message and movement. I have already been in contact with our police department to evaluate how best to prevent similar future incidents from happening. And, I expect and hope that other Critical Mass participants will condemn the behavior seen this past Friday and actively encourage their participants to respect everyone and all the applicable traffic laws while participating.

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