Listening to iPods and mp3 players while cycling in traffic? Texting or checking e-mail on a bike?
While most cyclists are aware of their responsibilities when it comes to safety, of how vulnerable they are, and that a body of traffic law also applies to them, others seem blithely unconcerned or uninformed.
"I think most cyclists have a good idea of how vulnerable they are without the shell of an automobile surrounding them, but many act in an ignorant manner, and we still have a long way to go in terms of the education of cyclists and motorists in the Charleston area," said Tom Bradford of Charleston Moves, a nonprofit organization promoting bicycling, walking, running and public transportation.
"I wish that these things were more universally understood," he said.
On Tuesday, a Charleston garbage truck struck a 15-year-old boy who authorities said was listening to a portable music player while riding his bike. The truck driver was not charged.
Bradford said he also has seen people talking on their cell phones while riding bikes.
"It's unfathomable to me. Yet when I tell people my life was saved twice by wearing a helmet, some are incredulous. With age comes a little more maturity. I hope this teenager will be all right, but I also hope that he and his friends may learn a lesson from this mishap."
You can counsel cyclists to exercise good judgment, obey traffic laws and always to be aware of their surroundings, but you also are dealing with a psychological gap, said lawyer Peter Wilborn, founder of mybikelaw.com, which promotes safety and protects the rights of cyclists in the Carolinas.
"You have to remember that it is very natural for people to be on a bike, that they do it in much the same (frame of mind) that they walk or run. People have always ridden a bike for recreation.
"And some see it more as walking around than like driving a car. Cycling kind of falls between being a pedestrian and being the driver of a car, and you want to preserve the best parts of those."
The problem goes deeper than rider awareness, Wilborn said.
"Given how people in the real world ride a bike, it goes back to infrastructure. Where in Charleston would you have a kid ride a bike? To school? To the library? To a park? We know that there are inadequate provisions for kids," he said.
"A West Ashley bike route that would allow people to parallel Savannah Highway has been in work for 20 years, with no progress. There also is no provision for cyclists downtown on King Street or on the College of Charleston campus, for example, though hundreds of cyclists go up and down these streets every day.
"So what are the planners and policymakers doing to increase safety?"
Wilborn said there has not been comprehensive bike education in the United States for years, but that his group has been working with the Charleston Police Department to get the word out on the importance of learning to ride a bike safely.
"It's not solely about personal responsibility. It is not illegal to listen to music while riding a bike or driving, you know. We want to encourage safety, but from an infrastructure standpoint, we are not doing a very good job of accommodating it."