By Sam Allis
They're the urban blurs - street rockets in Day-Glo and spandex slaloming around cars, freezing pedestrians in midstride.
Their speed costs them their humanity. They have no faces as they pass us at Mach 2. With those insect helmets and wraparound shades, festooned in clown clothes with earrings and tattoos, they belong to another species.
Nobody likes bicycle messengers until they need them. A 10-year veteran who goes by the name of Number 99 recalls what a lawyer once told him: ''I hate you when I see you going down the street, but I love you when you get my documents delivered on time in a bankruptcy case.''
Every walker has an anecdote about a near-death experience with a rider. And there are the horror stories - most notably the terrible collision in 1997 when a messenger almost killed Back Bay resident William Spring, who chose this week not to talk about it.
It is not comforting to learn that many use track bikes - single-gear models without brakes. Rider Mark Brady claims he can stop faster on his track bike by standing hard on the pedal than with regular brakes. I am unmoved by this explanation.
If they were irritants before the Spring accident, bike messengers descended to pond scum after it.
''There is definitely a negative view of us. We get yelled at all the time, even when it's their fault,'' says another Mark who refuses to give his full name. (This is generally a no name gang.) ''It's a good day for us when there is nothing in the papers about us. Pedestrians rule down here in the financial district.'' They're not supposed to. There is, in this blood sport between pedestrians and messengers, plenty of blame to go around. Boston walkers are, if it is possible, worse than Boston drivers. They wander the streets like padrones inspecting a vineyard. Streets, you recall, were invented for everything but foot traffic. ''Neither side is lily-white,'' says Sergeant Mark Cohen, director of licensing at the Boston Police Department. ''We're trying to keep both sides safe. Most bike messengers are hard-working, entrepreneurial people trying to make a buck.'' The year after the Spring incident, the state passed a law requiring all Boston bike messengers to be licensed and insured. There are about 200 of them this year who pay $25 for the license, says Cohen. Before then, Boston was a free-fire zone. Messengers confirm they have been plagued by more and more random license checks by the police. ''It started to get hard-core after the William Spring incident,'' says Rudy. ''Certain cops want to pull our chains,'' Riders also complain that the fine for pedaling without a license is $100 - is more than the penalty for riding a motorcycle without a helmet. So get a license. What part of this don't you understand? Messengers get hit, too. They have a verb - ''getting doored'' - when a driver gets out of his car without looking and sends a messenger over his handlebars. (Drivers are often the guilty parties.) ''I know of five in the last two weeks,'' says Number 99 about colleagues who've been doored. He's gone 21/2 years since his last injury. So what kind of hurt are we talking about here? Collarbones. ''You fall and there's no chance to catch yourself, so you get it on the collarbone,'' says Rudy, an eight-year veteran at 29. Collarbones take a while to mend. But the reality doesn't change: ''You don't ride, you don't eat.'' As independent contractors, bike messengers get no health insurance, no sick days, no benefits of any kind. ''You don't have a choice of coming to work or not,'' he says. Cohen calls them ''sharecroppers.'' Riders know all this going in and still favor the life over office claustrophobia. Even in winter. ''It's easier to keep the snow off our bodies than rain,'' says Number 99, who says it's his best time of year. ''There are fewer people on the streets and the cars go slower. You make more money then.'' The great existential question for bike messengers is this: How do you get out? At some point, your legs go. You get married, have a kid, and own a mortgage. Your resume is thin to say the least. Do you go back to school? Or are you locked in marginal jobs for the rest of your life? ''It's a black hole. That's definitely true,'' says Cyrus, a 25-year-old who has been a bike messenger for three years. ''It's probably been too long for me as it is. ''It's a fun job and the pay is secure, but it is stressful and kind of risky - but not gloriously risky. And I'm tired of being treated like a misbehaving child or a criminal.'' Still, the trade has its moments. Some corporate employees are so lazy that they will hire a messenger to ride a package in the elevator from one floor to another in the same building. ''101 Federal,'' says Number 99. ''Absolutely.'' Mark, by the way, takes top honors in the weird trip contest among a gaggle of riders waiting for calls in Winthrop Square. ''I used to take foreskins from the Brigham over to a place on Albany Street for skin grafts,'' he says. Yup. You win, Mark. If bike messengers want to forge better relations with the walking public, here's an idea: Lock your bikes up one day and wander around Boston in your gear. Talk to people. Introduce yourselves. Show them that you're part of the human race. A lot of folks might just say, ''Gee, he's just like my kid.'' Sam Allis can be reached at allis@globe.com