Under a new proposed law, the practice could become legal here, making Arizona more like its neighboring state and many European countries.
Yet while advocates see legalizing lane-splitting as a way to save time and improve safety for motorcyclists, some authorities worry it would lead to more crashes.
State Senator David Farnsworth, R-Mesa, recently introduced the bill for the coming legislative session, which begins in January. Farnsworth told the Arizona Capitol Times, which first reported the story, that he's not "passionate" about it, and that he introduced the bill after a request by a constituent.
In 2015, a study by the University of California, Berkeley, found that lane-splitting is "relatively safe" when performed at speeds under 50 mph.
However, Farnsworth told Phoenix New Times that he would become enthusiastic about lane-splitting if he saw more statistics that showed it was safe.
"I'm reasonably convinced that it will improve safety," he said, adding that he hopes to see facts and good debate about the practice in legislative committees next year.
The bill, SB 1007, strikes out the clauses in statute that make lane-splitting, also known as filtering, illegal. In other words, if the bill became law, it would allow motorcyclists to "overtake and pass in the same lane occupied by the vehicle being overtaken," and also would allow motorcycles to operate "between the lanes of traffic or between adjacent rows of vehicles."
The bill also directs the Arizona Department of Public Safety to "develop educational guidelines" for lane-splitting alongside other state agencies.
But there is opposition at the capitol.
"We don't like the idea," said Alberto Gutier, director of the Arizona Governor's Office of Highway Safety. Officials with the Arizona Department of Transportation and Department of Public Safety "agreed it's a very dangerous practice."
Former Governor Jan Brewer vetoed an Arizona bill in 2010 that would have allowed motorcycle lane-splitting for one year as a test in counties with more than 2 million residents. (Which meant only Maricopa County.) Brewer wrote in a veto letter that she was concerned that some people didn't see it as safe, and that one year might not be enough time to educate the public about it.
Lane-splitting has long been tolerated by police in California. The state further formalized the practice last year with a law that directs the Highway Patrol to develop guidelines for it.
Fatalities related to lane-splitting do sometimes occur in California, though, and it remains a somewhat controversial issue. In 2015, a study by the University of California, Berkeley, found that filtering is "relatively safe" when performed at speeds under 50 mph.
Still, polls have found that the vast majority of in California don't like it.
Arizona Confederation of Motorcycle Clubs, said he "absolutely" thought lane-splitting should be legal — for safety reasons.
Lane-splitting would likely "greatly reduce" rear-end collisions of motorcycles, he said. But he acknowledged it might take some getting used to by other motorists.
"It could be a little dangerous until the public was aware that it was legal," Eberhardt said. "I ride in California all the time. If they hear your bike, they move over and give you the space."
Lane-splitting would also save motorcyclists time. They wouldn't have to remain stuck in traffic — they would just cut through.
Farnsworth last owned a motorcycle in 1970, when he was a teenager. But like many Arizonans, he's driven extensively in California and has firsthand experience with lane-splitting.
When he's been caught in a traffic jam and seen motorcycles pass between lanes, "I honestly wonder whether it's safe," Farnsworth said "But I also think, man, what a practical thing for the motorcycle rider, because he's going to get there a lot faster than I will."