As many Minnesota motorcyclists hit the road for the first time in months, the increased ridership has brought a surge in accidents and prompted a plea for caution.

Five riders were killed in Minnesota in the past week, including two Thursday, according to the state Department of Public Safety. Those deaths bring this year's number of motorcycle fatalities to 11, the same as at this time last year. Crashes have injured at least 28 other riders since May 29.

In response, the agency issued safety recommendations for motorists and motorcyclists.

"Sadly, we have had two motorcyclists killed in Minneapolis within a 29-hour time span," Minneapolis police spokesman John Elder said Friday. "Every driver has to take the extra time to truly look for people on motorcycles — look twice.

"Additionally, if choosing to ride a motorcycle, wear a helmet," he said.

The motorcycle death toll has been rising in Minnesota and across the country. Motorcyclist fatalities in the U.S. had peaked in the late 1970s and 1980s, then dropped in the 1990s. But from 1997 to 2008, the number of deaths more than doubled. Minnesota logged 72 fatalities in 2008 — the highest number since 1985.

Of the five riders killed since May 29, four were not wearing helmets. In Minnesota, only motorcyclists under 18 or with instructional permits are required to wear a helmet.

The death toll includes:

Latimothy N. Saxon, 49, of Minneapolis, who was driving one of two motorcycles struck by a car Wednesday afternoon at Penn and 23rd Avenues N.

Patrick Rix, 42, of Duluth, an Iraq veteran who has been profiled in the Star Tribune. He was riding with a group of motorcyclists Thursday when he lost control and crashed on northbound Interstate 94 at Dowling Avenue N.

Gregory Cox, 55, of Burnsville, who died Thursday when his motorcycle sideswiped a car and then was struck by another car on Interstate 35W near Burnsville Parkway.

Jayson and Melonie Ingvall, of St. Francis, who were killed May 29 when they collided with a van making a U-turn on Hwy. 95 west of Cambridge.

Only Cox was wearing a helmet.

Bill Shaffer, program coordinator for the Minnesota Motorcycle Safety Center, remembers his first crash at 16, when he rounded a curve "a little too fast" and his motorcycle slid out from under him on the wet pavement.

Thankfully, he said, he was wearing safety gear, including a helmet — one of the conditions when he got his first motorcycle at age 10.

"I actually feel unsafe on a bike without one," he said.

Nationwide, 60 percent of motorcyclists wore helmets that meet federal safety standards last year; about 30 percent wore no helmet at all. Nearly 90 percent of riders wore compliant helmets in states where it's required, compared to less than 50 percent in states where it is not.

There's a strong community of riders who oppose mandatory helmet laws — even if they often wear helmets.

Jim Dahling is one of them. When he started riding at 16, helmets were mandatory in Minnesota. He still wears one most of the time, but sometimes decides to go without.

For him, it's about the right to choose. Helmets are personal protection devices, he said, and wearing one doesn't affect anyone but the rider.

"Motorcyclists are freedom-loving people," he said.

Unlike Shaffer, Dahling said he's never been in a crash — though he's lost friends in them.

Most motorcycle crashes in Minnesota last year were linked either to unsafe speeds by motorcyclists or to other drivers' failure to yield to motorcyclists.

"Many of these accidents are avoidable if the car drivers were paying attention," rider Gary LeMasters of Cochrane, Wis., said Friday.

LeMasters, who routinely visits the Twin Cities, said he's not dismissing the "incredibly dangerous behavior" that some of his fellow motorcyclists carry out, but added he's seen drivers of four-wheeled vehicles "reading the newspaper, putting on mascara, of course on the cellphone, text­ing, writing, eating and so on. They are very spoiled."

Among the 55 motorcyclists killed in 2012, 32 were 45 or older. Shaffer said he thinks a lot of these people started riding when they were young — around the time of the first spike in fatalities — but parked their motorcycles as they started raising families.

Now, with children grown, mortgages paid and retirement on the horizon, these riders are getting back on the road. Shaffer is one of those who started up again after years away. Riding takes skill and careful judgment, he said, but it's rewarding. "If you don't ride, it's kind of hard to explain," he said. "But I think for everyone who rides, there's a different piece of it that gets them."

Staff writer Tim Harlow contributed to this report. emma.nelson@startribune.com 612-673-4509 pwalsh@startribune.com 612-673-4482