From my experience living and daily commuting in SD, CA, I believe that lane splitting during a commute in SoCal is the rule rather than the exeption. There is a risk involved. It can be more dangerous than riding in a traffic free road. Does lane splitting have less than a risk than driving within the lane in bumper to bumper rush hour traffic? In my opinion, yes. Here's my justification: In non SoCal traffic, a risk of a rear end collision occurs everytime a car comes to a stop behind you. Most of the time this risk occurs at traffic lights. During bumper to bumper stop and go traffic, this risk occurs several times every minute that you are in grid lock traffic. You expose yourself to this risk everytime a car stops behind of you. (It is comparable to the number of miles driven per year. Statistically, the more miles driven, the greater the chance of an accident.) In comparison to lane splitting, I feel as though the risk of getting hit while lane splitting is far less than the risk of getting rear ended. In fact, I feel safest in stop and go traffic while riding between the front fenders of cars. In my opinion, drivers have a tendency to avoid collisions. Cars are less likely to side swipe each other or rub fenders. Drivers after all are not NASCAR racers. For this reason, I would rather ride in between cars.
The worst place to be as a lane splitting rider is in a blind spot. From the news reports of moto/car collisions that are lane splitting related, most of the reports are of car drivers who do rapid lane changes inorder to capitalize on opportunities to jump into openings in traffic. Many cagers do not check rear and side mirrors before perfoming lane changes. Rarely do cagers blindly drive into the sides of other cars. I cannot say the same for the miss judged distances that result in rear end collisions. As stated above, I do not want to be the meat in a car sandwich. From my experience and vigilant pursuit of moto v car news reports, rear end collisions occur more than fender rubbing... ergo, I lane split.
My definitions:
Lane splitting (aka lane sharing)- riding between lanes of traffic during stop and go traffic at a speed ~5miles above the rate of surrounding traffic (as long as traffic is moving less than or equal to 30 miles an hour.) At 30-35 mph, I fall back in line with traffic as it is now moving.
Filtering- riding between rows of cars stopped at a traffic light in order be at the front of the line at a light.
Lane splitting is not illegal in CA. As stated, CHP lane split all the time. As previously mentioned, CHP moto cops have pulled over once or twice in the past inorder to let me pass. how cool is that? My definition above is the "guideline" that a few CHP guys have told me i the past. It is not uncommon to see riders fly by stationary cars locked in grid lock at 50+ miles an hour. Those guys are significantly increasing their collision risks.
In my opinion (this will be my last one), any motorist who would even consider doing something malicious to a lane splitting rider is frustrated that someone is moving through traffic while they are not.
I have seen everything from dual sports to gold wings splitting lanes. if during a commute I see a non lane splitter, a majority of the time, the bike has non CA license plates. I agree with everyone and respect the reasons why they dont lane split or why they feel its unsafe to do so, but given the horrible commute times in SoCal, my risk benefit analysis favors splitting and filtering. Filtering alone (and not splitting) can safe a ton of time in itself. I never sit through more than one light cycle while at a stop light because Im at the front of the line when the light turns green!
In SoCal it can take as much as 15-20 min in a car to just get onto the freeway as there are stop lights on the entrance ramps limiting the rate of vehicle entry. The line to get to the enterance ramp can be a mile long. Because a bike can get on the HOV entrance ramp it takes one minute to enter the freeway. Time savings: 19 minutes. When you do finally get on the freeway the cager will be crawling in stop and go traffic. Depending on how far on the freeway you travel, the commute time may vary. If you compare not moving in a car (2-3 mph) to moving at a safe lane splitting speed of 25 mph the time savings can be as much as 75%.
A typical traffic free commute on the freeway of 10 miles can be covered in 10 minutes. one mile every minute is 60mph, assuming that you dont speed. no one speeds in SoCal, right?
in certain areas of SD and LA namely the 5, 405, 805, 710 and 210, the 10 mile commute in a car during rush hour can take over an hour. The same commute lane splitting can be done in about 20 minutes. Time savings: 40 minutes. Total savings: 60 minutes. I made this commute everyday and dreaded the days taking the cage to work. A 21 minute commute on the bike became 1:20 in the cage.
The average CA cager knows that lane splitting is allowed. Most of them know about it and accept it. In fact, every foreign country I have ever been to accepted it as well. HK, Manila and Mexico City come to mind. Sorry for the rant, but Ive been in this conversation a ton of times. The more I talk about it the more the cagers keep an eye out for all of us.
one less car means we get home sooner.