How can I prevent cars from passing me too closely? Recently, a driver buzzed by me, leaving just a couple of inches between my handlebars and his car. It was very scary.

In general, how can I prevent cars from passing me too closely?

Please cite sources.
Use proper positioning. This is most important. Unless the outermost lane is as wide as two SUVs, ride in its center. When it's safe, reasonable and necessary to let drivers pass, kindly move over; but always leave at least 18 inches (0.5 m) between you and the curb. The driver behind you may have to wait a minute or two, but they'll survive. If they've waited a few minutes, be nice and pull over. (Adapted mainly from Wikipedia citing Cyclecraft.) Paradoxically, correct positioning will stop most drivers from buzzing you. Correct positioning can be scary, but does get easier.


There's more to vehicular cycling. You must read more about lane release. Also read "Street Smarts" online: either the American edition or left-hand-drive edition. If you want, you can also read Cyclecraft, or take a class, or watch some videos. (Can anyone recommend some videos?)

On rare occasions, drivers may still buzz you. To prevent this:


Use a safety flag. A spring-mounted one: e.g. a Flash Flag. (Source.) It must be spring-mounted, so that it can bend easily if hit. (If you can't afford a flag: Maybe you could use a dollar-store pool noodle plus a washable marker pen. See here.)
Or use a doll. Put a baby-sized doll in a trailer or rear-mounted carrier.

About attempted murder: If a driver ever intentionally endangers your life, note down the license plate number, location, time, and date. If you value your safety, don't touch the driver's car. Contact a cop: preferably immediately; but better later than never.


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