You're driving down the Hollywood Freeway and you see a guy in a two-ton SUV, somehow holding the steering wheel while texting at 65 mph.
A few minutes later, you pull off onto Sunset Boulevard. While you're waiting at a signal, a skinny guy on a four-pound touring bike speeds past and runs the red light.
Which of these two men is the greater threat to public safety? To me, the answer is obvious. But to many of my readers, it's the guy on the bike who's the menace.
"I, personally, find most cyclists on the streets of Los Angeles to be perfectly obnoxious," Liz White, a resident of the Village Green, wrote to me last week. She described one recent incident in which she drove slowly behind, then passed, two slow-moving cyclists riding side-by-side on Mentone Avenue in Culver City.
Moments later, she looked in her rear-view mirror and saw both cyclists flash a raised middle finger.
"Why? I have no earthly idea. Except that, it seems to me, many if not most cyclists have Westside-itis," she wrote. "They think they're entitled to what they want whenever they want it, and everyone else be damned."
In the wake of my column last week urging Angelenos to recognize the right of bikes to share the road with drivers, many readers wrote to me with similar tales of aggravation inflicted by the pedaling tribe.
Several, like White, described cyclists flippin' the bird.
I've never suffered that particular insult. But I have seen plenty of bike-riding behavior that leaves me shaking my head. For starters, people biking without helmets. Cyclists riding with earphones on — an accident waiting to happen.
People can be as reckless on a bike as they are behind the wheel of the car. But stupidity with no steel around you to protect you is a more naked, brazen kind of stupidity — and that's what drives a lot of Angelenos batty.
Daniel Zogaib of Orange, paralyzed when a car rear-ended his motorcycle in 1988, told me he couldn't believe anyone would cut in front of a ton of steel moving at 30 mph.
"To have people cutting through traffic and running red lights on bicycles that don't have enough power to get out of the way is completely ridiculous," he said.
And yet, having read all of your complaints, I still believe that cyclists have as much right to the road as drivers do. Just because a few people abuse a right doesn't mean the right should be denied.
I know many readers will hate me for saying this.
"So will you be campaigning for horse lanes next?" wrote John Daykin, a Westlake Village property manager. He calls bicycles an archaic, "19th century" conveyance. "The roads are not built for cyclists; they are an unregulated hazard to normal traffic."
Sorry, Mr. Daykin, but the law's not on your side.
"It's the mindset of drivers to think, 'I want to keep going straight and anyone who prevents me from doing so must be wrong,'" said Sgt. Christopher Kunz, of the LAPD's West Traffic Division. "But the simple fact is bikes have a right to be on a road. We all just have to recognize they're not as fast as we are."
Of course, there are caveats:
"All the rules of the road apply equally to bikes and cars," Kunz said. So bikes must have lights at night, stop at all stop signs and obey all other laws.
Slow-moving bikes must ride near the right side of the road, Kunz said. But cyclists still have the right to use any lane. "I can't cite a guy for using the left lane to make a turn," Kunz told me.
The law also states that an officer can cite anyone who moves so slowly as to cause a traffic hazard. A cyclist pedaling at 5 mph in the middle of a lane with a 45-mph speed limit would probably be cited for doing so. But a cyclist doing 30 mph in the same lane might not be.
"There's a lot of ambiguity in the law," Kunz said.
It seems clear to me that, as more bikes use our streets, we need to put more effort into spreading the word about safe and courteous biking practices.
Joe Linton, one of the city's leading advocates for bicyclists, agrees.
"We all assert our rights to use the streets, whether we're biking, walking or driving," Linton told me. "And we should all be more aware and more courteous of each other."
Linton also favors the kind of redesign of major thoroughfares that would make cyclists safer, while forcing cars to "slow down a bit," he said.
The cycling lobby wants to make L.A. a little more like bike-friendly Copenhagen and Amsterdam. But resistance is deep. Already, the car-cycling debate is shaping up into a culture clash.
Jim Trombetta, a novelist and television writer, told me he is appalled by the "moral superiority" of the cyclists he's encountered. Many are deliberately flouting the law, he wrote, and their rudeness "appears almost ideological, as if a school somewhere taught it."
Mr. Trombetta, I feel your pain. It was already hard enough to get around L.A. without being forced to share the road with the growing hordes of people who insist on a healthy lifestyle.
But there's no arguing with the fact that in a crowded, sedentary city, with too many cars and too much obesity, more bicycles is a better thing.
So the next time I'm forced to slow down and navigate my car around two guys pedaling leisurely on my favorite thoroughfare, I'll try to remember the three words of advice Sgt. Kunz left me with: "Patience, patience, patience."