The breaking point for Steve Herlth came when he saw about 25 dirt bike riders swarm around him on West Baltimore's Hilton Parkway, popping wheelies, creating a racket and showing no regard for surrounding traffic.
That surreal scene led Herlth to start a campaign urging residents in his Southwest Baltimore community to turn in the youths and adults who own the illegal cycles. But his yearlong work — and the efforts of authorities — has not stemmed a problem that bedevils Baltimore each summer and threatens to worsen when schools let out soon.
Riders still roar up city streets, bobbing and weaving through traffic. In recent days, police have responded to two serious accidents involving dirt bikes. On Wednesday, the driver of a car was hospitalized after an attack that followed a crash with a bike. Two days earlier, a motorcyclist was killed after he crashed into a pole while trying to avoid a dirt biker carrying a 2-year-old child.
"What took place [Wednesday] with that man being beaten is totally uncalled for. There is no excuse for that whatsoever," Herlth said, adding that he isn't giving up the fight against dirt bikes.
Neither are city officials, who in 2008 and 2010 passed laws aimed at corraling the bikes. Other cities, including New Haven, Conn., and Camden, N.J., have focused efforts on dirt bike riders, creating special police teams and urging residents to report the illegal activity.
Still, eliminating the decades-old problem isn't easy, Baltimore leaders say.
"Riding through traffic in Baltimore is a thrill-seeking activity, and it's got to stop," said City Councilman William H. Cole IV. "But I'm kind of at a loss. If you can't catch them, it's hard to enforce."
Baltimore police have long said their options are limited, saying that it is too dangerous to chase dirt bikes through city streets. A spokesman for Mayor Stephanie C. Rawlings-Blake said she would like to better use technology to help police combat the bikes and encourage residents to report places where they are stored.
Wednesday's attack happened after the driver of a dirt bike plowed through a red light at a West Baltimore intersection and broadsided a red sedan. Police say a passenger on the bike hid it in an alley and returned with friends, beating the car's driver so badly that he had to be taken to Maryland Shock Trauma Center.
Two days earlier, 44-year-old Alphonso Gaye of Greenbelt died after striking a pole at Gilmor and Fayette streets. The driver of the dirt bike fled after dropping and slightly injuring the toddler, who was taken in by relatives nearby.
Some bike riders have questioned why riding the vehicles is illegal, adding that most riders cause no problems and are even embraced in a few neighborhoods.
Although violent incidents like those this week are not the norm, city leaders are growing tired of rebellious teenagers and young adults, the primary riders of the bikes, some of which can cost more than $1,200.
A law passed by City Council will prohibit gas station owners from dispensing fuel to dirt bikes; it takes effect Oct. 1. How successful such a campaign will be remains to be seen, especially since many dirt bike owners do not gas up at stations, instead putting the fuel in canisters.
"I feel like, initially, it will be a great help in curbing the problem," said police spokesman Donny Moses. "But of course, like everything else, criminals adapt, and they'll find a way to fuel up. And gas station owners are in the business of making money."
In September 2008, a law took effect that allows police to seize any unlocked dirt bike — in an alley, driveway, front yard or street. A court can then order the bikes forfeited, and they are destroyed.
But that law has had a limited impact. Police have not received many calls about the location of the bikes — which Herlth attributes in part to a "fear factor." He added, "And then, No. 2, it's just pure laziness by some of the people."
City leaders say they have looked at how other localities combat dirt bike lawlessness but have not found an effective model.
New Haven police devoted 12 officers each day last year to finding, stopping and confiscating the vehicles as part of a "quad squad." But the effort was not embraced by some officers, who thought stopping bikers would open up the opportunity for a chase that could cause more harm than good.
In Camden, Angel Fuentes, who represents the 5th District in the New Jersey Assembly, said dirt bikes "are just out of control." To cut down on the illegal driving, he said, the city has launched a campaign to increase the number of signs in city parks; there is no dirt bike park available for riders. The new campaign also includes "educating the public that they are illegal to drive them on the streets."
He said it's an uphill battle for police, "who are trying to track down riders by tips from the neighborhood, rather than chasing riders."
Other cities have proposed bike parks — an idea not endorsed by Cole, who said riders get their thrills by riding on city streets.
"The best way to get the bikes is to locate them and seize them," Cole said. "But we need cooperation of people in the neighborhoods. These bikes are coming from somewhere. … You've got to get them at the source."
Baltimore Sun reporters Jessica Anderson and Justin Fenton contributed to this article.