SAN DIEGO -- There were two motorcycle deaths over the weekend in the county and a third during Monday night's rush hour. Motorcycle deaths are on the rise across California and the nation while total highway fatalities are dropping. 10News reporter Allison Ash looks at one reason behind the spike.

Lane-splitting or white-lining is when a motorcyclist rides to the side of a car in the same lane or between two cars driving side-by-side. It's a practice many bikers love but other drivers on the road hate.

"A lot of cyclists like to do bold and brave things that they're not really supposed to do on public highways and that makes it more dangerous for everybody else," driver Joshua Batie said

Driver Regina Howard said, "They're cutting people off more often and scooting in-between cars and I don't know if they're following the rules."

California is the only state where lane-splitting is legal. The CHP said the practice is safe in heavy traffic when the motorcycle is going less than 12 miles per hour. In other words: speed kills.

CHP officer Brad Baehr said, "They're too fast and often times riding equipment and machinery that's way outside their skill and experience level."

The National Highway Transportation Safety Administration said that motorcycle fatalities have been growing nationwide for more than a decade. In San Diego last year, 55 bikers died on the road compared to 43 in 2004.

While most morotcyclists obey the rules of the road, the CHP said a few bad apples spoil it for the rest.

"You have a small percentage of thrill-seekers that are riding fast and have been popularized by YouTube and do stunts. All that requires skill, unfortunately. None of that belongs on public streets and highways when you're sharing the road with other drivers who, quite frankly, aren't looking for you," Baehr said.

The number of fatal accidents in California is slightly below the national average.

When it comes to the practice of lane-splitting, a majority of San Diegans think it should be illegal in California. That's according to our exclusive 10News poll. Of those participating, 63% think lane-splitting should not be allowed in the state, while 32% believe it should be allowed.

» Exclusive 10News Poll Results