OFF THE WIRE
http://www.twincities.com/ci_16107071?nclick_check=1 Street-crack sealer called deadly for motorcyclists Crack sealer — which can cause motorcycles to slip — litters the intersection By Jessica Fleming jfleming@pioneerpress.com Updated: 09/18/2010 05:10:20 PM CDT
For most motorists, the tar that seals cracks on the road is at most unsightly.
But for those who drive on two wheels, that sealant can be deadly, especially when overapplied.
Motorcycle-safety courses warn of what they call "black-tar snakes," but accidents still happen, and safety advocates want to change the way highway crews apply the gunk.
Tar snakes litter the intersection where off-duty Lakeville police Sgt. Brigham Strole was killed Sept. 1, but investigators say they are still unsure what caused his motorcycle to sway just before he was thrown from his bike and killed.
"Any irregularities or changes in the road surface have the potential to be hazardous, especially to a two-wheeled vehicle that doesn't balance on its own like a car," said Lt. Eric Roeske, spokesman for the Minnesota State Patrol, which is conducting the investigation. Investigators said it likely will be at least a few weeks before the official cause of the crash, if it can be determined, is known.
Strole, who lived on the Lakeville street where he crashed, was an experienced rider, Lakeville Police Chief Thomas Vonhof said.
But so is Bob Zick, 64, of St. Paul, who is still recovering from a July crash in which he slipped on tar snake while riding around Lake Phalen.
"The stuff is really deadly," said Zick, who has been riding motorcycles for 40 years. "Especially when you hit it and you don't expect it."
Zick crashed on a hot day, when the tar can be particularly slippery. Zick was wearing a motorcycle jacket and a helmet, which he said probably saved his life. He underwent surgery for his broken clavicle and shoulder. Strole was not wearing a helmet.
"Wearing protective gear can really take the bite out of small mistakes," said Pat Hahn, information officer with the state Department of Public Safety. "Protective gear can change a life-changing experience into a learning experience."
STEALTHY HAZARDS
Most riders know to look out for tar snakes, particularly when it's wet or hot, motorcycle-safety advocates said.
A web of cracks mars the intersection where Strole crashed. Many run parallel to the curb. When a snake is perpendicular to the roadway, it's a short disruption for a cycle's tires. But skidding along a parallel crack can be unsettling, Hahn said.
"When you get those tar snakes that are parallel, they can really upset your feeling of stability," he said. "It's enough, even in a gentle curve, to cause your bike to go out from under you."
Zick was turning a corner when he hit the tar.
Strole had just turned onto Jordan Court and would have been maneuvering up a sloping hill. Keeping a bike steady is more difficult during acceleration, which could explain why witnesses saw his cycle sway before he was ejected.
"Tar snakes are more of an issue when you're slowing down or accelerating," said Pete terHorst, spokesman for the American Motorcyclist Association.
Motorcycle-safety groups said they don't have statistics on how many crashes are caused by tar snakes. Often, the rider simply loses traction for a time and recovers.
Of Minnesota's 1,329 motorcycle crashes last year, 47 were fatal.
REPAIR METHOD MATTERS
The way the tar is applied can determine the degree of danger for cyclists, advocates said.
The Motorcycle Safety Foundation recommends what it calls a "flush-full, strike-off" method for applying tar. Basically, that involves putting as little tar as possible in a crack and scraping off the excess.
"If crews were perhaps a little more careful in their road maintenance, motorcyclists would have one less thing to look out for on the road," said Robert Gladden, general manager of the foundation.
But those in charge of fixing local roads say they already use as little material as possible.
The Minnesota Department of Transportation employs the "overband" method, which involves overfilling the crack and rolling over the excess to create a swath three-quarters of an inch wide on either side.
State pavement engineer Curt Turgeon said that's to protect the damaged pavement and keep the crevice from widening.
"You want a little of that glue up on the top and around the edges," Turgeon said. "It keeps it from pulling away quite as quickly."
Turgeon said keeping the tar as hot as possible and using a minimum of the gooey stuff is key to keeping the road surface safe.
"I ride a motorcycle, and there are some roads I come across where it wasn't applied very well," Turgeon said.
Most governments contract out for the work, Turgeon said, and there's not a lot of quality control.
Lakeville contracts for its crack repair, said Chris Petree, the city's operations and maintenance director.
"But I can tell you most of them are very reputable folks, and they follow the MnDOT specifications," Petree said.
The cracks near Jordan Court and Jonquil Avenue, the intersection where Strole crashed, were sealed about a year ago, Petree said.
SLOW AND STEADY
Motorcycle-safety advocates say slowing down and keeping your bike as upright as possible can help when approaching a hazard.
Other treacherous surfaces include leaves, especially when wet; manhole covers; sewer grates and even the lane stripes painted on the roadway.
"When those lines get wet, they're like ice," said Hahn, of the Public Safety Department.
Hahn said he tells bikers not to panic when they hit a slippery surface.
"Maintain your concentration and your path of travel," Hahn said. "You can either ride it out or you can give up. Giving up is the worst thing you can do."
Additionally, riders can practice the most fail-safe safety method: avoidance.
"When you get into a mess of tar snakes, it's like walking into a ditch of real snakes," Hahn said. "We all try to avoid roads that have those things."
