On my way to KQED the other day, I pulled up next to a fellow bicyclist who shot me a quizzical glance. "Do you know whether we have to follow traffic regulations?" she asked.

Umm....Yeah.

I'd like to say her ignorance surprised me. But it was hardly the first time I stumbled across gross confusion about the place of bicycles on the road and in the law.

A couple of years ago, my son reported that one of his friends thought bicyclists weren't allowed on streets at all — only sidewalks.

Then there was the guy in the truck who stopped me on Brannan Street to direct me to a bike lane two blocks over. And nearly every week a motorist honks at me for no apparent reason.

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Such confusion is all the most important these days because, as the number of bicyclists increases in the Bay Area, so does the potential for accidents.

On Tuesday, Chris Bucchere, a cyclist accused of killing a 71-year-old pedestrian who was crossing the street in the Castro district in March 2012, appeared in court on manslaughter charges.

The hearing was mostly procedural, but the San Francisco district attorney's office has emphasized the importance of traffic regulations in the case. "... Multiple witnesses took the stand, and court testimony indicated that Mr. Bucchere ran three red lights and a stop sign at over 30 mph before killing Mr. Sutchi Hui," the San Francisco district attorney's office said in a March 22 statement.

Bucchere's attorney did not return my call, but earlier he told the San Francisco Chronicle that Bucchere thought he had obeyed all the rules.

It might take a jury to ultimately sort out what happened in the accident. So, in the meantime, here are some important — and perhaps surprising — facts for cyclists, motorists and pedestrians to keep in mind on Bay Area streets.

1) Bicyclists don't have to ride in bike lanes, or even stay to the right.

In general, California law calls on cyclists to stay to the right and use bike lanes when available, but cyclists can ride elsewhere if they find it safer to do so.

Specifically cyclists can ride in the left part of a lane to make a left turn or on the left side of a multi-lane, one-way street.

They can move into the middle of the lane to avoid obstacles -- including when cars are parked along the curb, because motorists often open car doors and can knock cyclists down.

Bicyclists also can move away from the right side of the lane near intersections where motorists might want to make right turns in front of them.

2) Bicyclists are required to use a light and reflectors at night. They must have a headlight and reflectors to the rear, on each "pedal, shoe or ankle," and on the sides of the bike.

3) Cyclists must yield to pedestrians. In California, unlike many other states, bicyclists have to stop for people crossing the street on foot, just as motorists do. Bicyclists can take advantage of the same right of way by dismounting. As long as they are only walking their bikes, they become pedestrians for the purpose of the law.

4) Bikes have to stop at stop signs and traffic lights. As frustrating as it might feel when you've pumped your way to a beautiful speed, you can't just sail through a stop sign, even if there's no one else in the intersection. Bicyclists can't go the wrong way on a one-way street either.

5) Bicyclists can ride on sidewalks, but the rules vary from one community to another in California. In San Francisco, you can't ride on a sidewalk after you reach age 14. In Oakland, you can ride on a sidewalk if your bicycle has wheels of less than 20 inches in diameter or a frame of less than 14 inches in length.

How about Silicon Valley? Here's what the Peninsula Press found out in researching that question:

Sidewalk cycling laws vary by jurisdiction in the South Bay. Riding on the sidewalk is legal everywhere in San Jose but illegal in other cities, including nearby Campbell. Other neighboring cities, like Sunnyvale and Gilroy, allow cyclists on sidewalks everywhere except business districts as defined by a city’s municipal code. Mountain View has the same restrictions, but in business districts as defined by the California Vehicular Code.

You have a week to bone up: bicycle groups are celebrating Bike to Work Day May 9 around the Bay Area.

Chris BucchereChris Bucchere

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