SOHO. A new bike safety law takes effect today requiring delivery workers to wear helmets on the job, and members of the city's bike messenger community are in a spin."[Wearing a helmet is] something that's not cool. You look kind of dumb," said Carlos Ramirez, 32, a 12-year messenger veteran and a Team Puma racer. "I really don't want to wear a helmet, but I will."Ramirez began wearing a helmet last month, motivated by the law and a friend who hit his head in a bike accident. The new law mandates employers provide head gear, but Ramirez didn't want just any helmet."I got a really beautiful $200 helmet worn by [cyclists] in the Tour de France," he said. "It's really light, so you don't really feel it."Some messengers don't care about the $25 to $50 fines. Employers failing to provide helmets could pay up to $250."It should be your choice," said messenger Scott "Ham" Hamilton, 36. "It's not like you're on a motorcycle. You're not going that fast."He's no stranger to accidents in his 13 years on the job. He estimates having hit more than 100 jaywalkers."I've never seen a jaywalker get a ticket, but when they cross, they don't look," he said. "But I've got to wear a helmet?"He wore a helmet once "to make my grandmother happy." He doesn't plan to start wearing one now.Hamilton and Ramirez are bitter the law only affects commercial cyclists."What about the people that commute on bikes and don't wear helmets?" asked Ramirez. "They're the ones with less skills. We do this every day. We know the roads and traffic. A lot of people who just commute look like messengers. How are the police going to know who's a messenger? Now they're going to search your bag?"Noah Budnick of advocacy group Transportation Alternatives agreed that enforcement might be unreliable."We think it's more efficient to enforce at the business level," Budnick said. "Turnover is so high at these jobs. It doesn't make sense to stop individuals."The city requires helmets for cyclists under 14. Budnick explained advocates haven't pushed for a citywide mandate because "anything that could discourage biking -- like mandating helmets or bike licenses -- means there will be fewer riders and that makes it more dangerous."Free helmetsThis week, the city's Dept. of Transportation gave out hundreds of free helmets to delivery workers in Chinatown. Since June, it's given away 2,000 helmets and aims to distribute 4,000 more.