It can be unnerving when a biker pulls up to a car and revs the engine. It can seem unsafe, but riders like Jimmy Nikides do it to save time.
"When traffic is really bad, I don't have time to sit behind cars waiting for 90 minutes to get to work. When I lane split, I get to work in 40 minutes," said Nikides, who has been commuting on his Victory motorcycle for almost five years from his home in the East Bay to his job at ABC7 in San Francisco.
We followed Nikides on his commute one day and watched him squeeze in between rows of cars on Interstate 80, at times maneuvering between large buses and big rigs.
Lane splitting can seem terrifying or irresponsible for motorists.
"People love to complain about lane splitting. I think it scares people," said Nikides as he prepared to head home.
Nikides admits lane splitting can be dangerous so he rides conservatively. Despite its risks, lane splitting is allowed by California law.
In 2017, the state added section 21658.1 to the vehicle code. It defines lane splitting as driving a motorcycle "that has two wheels in contact with the ground, between rows of stopped or moving vehicles in the same lane."
California became the first state in the country to legalize lane splitting. (Utah approved it in May)
It wasn't necessarily illegal before this definition. There was no law restricting it.
There are 12 other states, including Texas, Ohio and North Carolina that tolerate it under the same ambiguity, while most other states prohibit it.
California decided to allow it for two reasons. It reduces congestion when motorcycles replace cars, and it is actually safer for riders. Yes, safer.
"When there is a lot of stop and go traffic, a small fender bender between two vehicles, is not really a big deal, however, if there is a motorcycle in between that could be catastrophic," said Officer Art Montiel of the California Highway Patrol.
A 2015 study by the Safe Transportation Research and Education Center at UC Berkeley found that only 17-percent of motorcycle crashes between 2012 and 2013 involved lane splitting, so it does not seem to increase crashes.
While the 2017 law allowed lane splitting, it stopped short of regulating it. That is why last year the California Highway Patrol released a set of guidelines for motorists.
"They should not be going more than 10 miles per hour over the speed of the other vehicles.So if traffic is moving at 15 mph, they probably should not be going more than 25 mph," said Officer Montiel.
Keep in mind this is a safety recommendation. There is no required speed limit for lane splitting but an officer can still ticket a rider who is riding recklessly.
The CHP also recommends riders lane split on the far left lanes and avoid lane splitting next to big rigs, buses and other large vehicles. Riding on the shoulder of the road is illegal and not considered lane splitting.
And about that engine revving-- there is nothing prohibiting it. Officer Montiel admits riders need to do it sometimes to increase their visibility.
"They are trying to get people's attention because a lot of times people are distracted while they are driving. They want to let them know that they are there," said Officer Montiel.
"The problem is that sometimes the motorcycle is a little too loud and if drivers are not paying attention, they will be rattled a little bit."
Nikides admits he revs his engines too.
"I want to let them know I am back there if they get too close to the line. Most people do move out of the way. Then there is the occasional car that won't budge. I don't know why," said Nikides.
Should you move over? The CHP would like you to.
"Drivers are not required to move over but it would be helpful if a motorist can move out of the way for the motorcycle to pass safely," said Montiel.
While motorists are only encouraged to move over, they could get a ticket if they intentionally block or impede motorcyclists in a way that could cause harm to the rider.
"I am surprised when I talk to people who are angry or resentful that we can do that. I am not sure where the resentment comes from. Some people feel like if I can't go, then they can't go either," said Nikides. "Most of us are trying to drive safely. Let's all go where we need to go safely."