Minnesota public safety officials have reminded motorcyclists and motorists to drive carefully and share the road following two rider deaths this week.

Motorcycle fatalities are at the highest level seen since 1985, a trend that shows no signs of slowing.

On Monday, a 62-year-old man was killed after colliding with a semitrailer truck and a passenger vehicle on Interstate Highway 35 near Duluth. On Tuesday, a male rider, aged 43, was found dead on Hwy. 19 in Lincoln County after missing a curve and colliding with a road sign, according to the State Patrol.

The Minnesota Department of Public Safety (DPS) reports that 70 motorcycle riders died in 2006, an increase of nearly 200 percent from 10 years ago.

The number of fatalities continues to climb: 24 riders have died in 2007, compared to 21 at this time last year.

"The four most common factors attributed to motorcycle crashes - speed, inexperience, impairment, and inattention - are all within the rider's control," says Katherine Burke Moore, deputy director of the state's Office of Traffic Safety.

Burke Moore encourages riders to slow down, ride within their limits, stay sober, and pay attention. "Riders should assume they are invisible to other drivers, wear protective gear and take safety training to hone their skills."

Vehicle drivers share responsibility for motorcyclists' safety. Nearly half of all motorcycle crashes involve another vehicle. The most common factors attributed to other drivers are inattention and failure to yield the right-of-way.

Said Burke Moore: "Take a second look for motorcycles. They are smaller than other vehicles and it's more difficult to judge their speed and distance."

Motorcycle ownership has nearly doubled in the last 10 years. Motorcycles make up about 4 percent of all registered vehicles, but represented nearly 14 percent of all motor vehicle fatalities in Minnesota last year.