Forty-seven motorcycle riders have died on Minnesota roads so far this year, surpassing the total number of all rider fatalities in 2014, the Minnesota Department of Public Safety announced Monday.

There were 46 rider fatalities all of last year – and in 2015, there are still two months left in what's considered riding season. These fatalities are up 47 percent compared to this time last year, when there were 32 rider deaths.

“More than half of these riders (31) weren’t wearing a helmet when they crashed, and half of these fatal crashes were single-vehicle crashes involving only the motorcycle,” Bill Shaffer of the Department of Public Safety Minnesota Motorcycle Safety Center said in the news release.

Failing to yield is the most-cited contributing factor in fatal crashes, while losing control around a curve was a factor in 19 crashes. Speed was cited in 11 of the crashes, the release says.

“These are preventable. We strongly encourage riders to take a training course, wear full protective gear and slow down. It could save their life," Shaffer added.

A motorcycle fatality Monday morning marked the 47th rider death this year, the Department of Public Safety told BringMeTheNews.

The Lakeville Police Department said in a news release that 57-year-old Wayne Robert Dewolf collided with a parked piece of construction equipment around 5 a.m. Monday. He wasn't wearing a helmet.

The release notes he drove around a barricade marking a closed road, and onto a portion of road that was under construction. He was pronounced dead at the scene.

There were a handful of other motorcycle crashes over the weekend that caused injury to the riders, the State Patrol's report shows, and at least one rider fatality.

Neville Amundson, 58, died after rolling his motorcycle on Highway 61 in Cottage Grove Saturday night. He wasn't wearing a helmet.

The State Patrol incident report says he was traveling at a "high rate of speed" around a curve over a hillcrest when he lost control.

There are more than 236,000 registered motorcycles and more than 414,000 licensed operators in Minnesota, the Department of Public Safety says.