This has been a deadly summer for local motorcycle riders.

Ten motorcyclists have died in crashes in about a four-week period in Lancaster County.

A watch repair technician died when his cycle ran off the road on a sunny morning near a Manheim Township neighborhood. Two 20-year-old buddies died when their motorcycle hit a tree that was downed during a summer storm one night in Martic Township.

And five friends, including two married couples, died in a crash after they collided with a van during a Sunday afternoon ride down Route 72.

So far this year, 14 motorcyclists have died in crashes.

Since 2005, anywhere from seven to 17 motorcyclists have died in crashes here during a calendar year.

There are still almost six months left in 2010, including the rest of the summer and fall, which are boom riding months.

It's difficult to say why the county is experiencing an apparent spike in deaths from cycle accidents this year, officials said.

This summer's crashes have varied greatly.

Some happened on bright days and others after dark fell. Riders' ages ranged from 20 to 50. They were riding both sport bikes and larger touring bikes.

The causes of many of the crashes are still under investigation.

State police Lt. Jeremy Richard said the number of fatal crashes might be due, in part, to the time of the year, and the fact that cyclists and drivers both have to adjust to motorcycles being back on the road after winter's hibernation.

"If you could put it into the bigger picture, we haven't seen people riding their motorcycles for many months. This is the riding season," said Richard, head of the patrol division at the Lancaster barracks.

Statewide, statistics show that the number of fatalities does shoot up during summer months simply because that's when most motorcyclists are on the road.

Since 2005, statewide statistics show the highest number of crashes has occurred in July in every year, except for 2007, which showed the highest number in June.

Everybody has to be on the lookout, said Richard, a state transportation department worker and a motorcycle rider.

"It's a very important thing for everyone to remember, from the car driver to the motorcycle rider: Use common sense," said Danielle Klinger, a PennDOT spokeswoman who deals with motorcycle safety.

This spring, PennDOT launched a motorcycle safety campaign called Live Free Ride Alive.

Motorists need to double-check and triple-check their blind spots when near motorcyclists, Klinger said.

Richard added, "We've seen a higher number of motorcycle crashes as a result of automobiles pulling out from stop signs. The motorist really needs to come to a complete stop and really look twice before they pull out."

Chuck Becker has seen it all during his 35 years of riding motorcycles. The 58-year-old Lebanon man is the president of the Lancaster-Lebanon Liberty Riders, a chapter of ABATE, Alliance of Bikers Aimed Toward Education.

"If I come to an intersection and there's a car sitting there, I assume he's going to pull out in front of me, and I start slowing down and planning evasive action," he said.

Why does he do that?

"Ninety percent of the time, they do pull out in front of you," said Richard, who said his 128-member chapter distributes yard signs that say, "Look twice, save a life."

The most common crash scenario, according to a 2009 study by the state, involves a motorist making a left turn in front of a motorcyclist.

That's what happened in the most recent fatal crash, which happened Monday in East Cocalico Township, according to police. Carol Ann Borry, 84, of Mount Joy, tried to turn left in front of Bradley Weber, 46, police said. Weber was thrown from his motorcycle and died a day later.

Motorcyclists also need to operate safely, officials say.

Speed and alcohol use are the biggest risk factors in motorcycle crashes, studies show. Klinger said that speed is the biggest factor in younger, sport bike riders' accidents, and alcohol is the biggest factor in older, cruise bike riders' accidents.

Helmet use is controversial among some bikers but studies show riders who wear them are three times more likely to survive head injuries, according to the "Live Free Ride Alive" website.

Becker wears a helmet but believes it should be a motorcyclist's choice. They won't protect a rider in a high-speed crash, he said.

But Richard said they can help at low speeds. In a Chester County crash, a motorist was traveling about 10 mph and was involved in a crash with a motorcyclist that put the bike on the pavement, scratching it, and causing the cyclist to hit his head. The cyclist was walking around at the crash site but died a few hours later, Richard said.

Becker said safety classes also help motorcyclists. Programs are free in Pennsylvania and, he said, "You're crazy if you don't take them."

He urges new motorcyclists to take their time and learn how to operate their motorcycles safely.

The five-fatality crash on Route 72 has been particularly sobering to local motorcyclists, Becker said, as the victims were killed while traveling in their own lane and, he said, appeared to be following traffic laws.

"My wife is my passenger and we usually ride with a few other bikes," Becker said. "You don't think that the next time I went to get on my bike I didn't stop to think about that?

"You can follow every rule in the book and it can still happen to you."

cstauffer@lnpnews.com