Vintage BMW Motorcycle Owners




Knowledge Base




Snowbum's BMW Motorcycle Repair & Information Website

Google-sponsored advertisements are at the top of every page.
Clicking on them at every visit helps support this website!
Clicking on something inside an advertisement helps even more!
For history of this website, how it is run, and information on
donating:  CLICK


Lane-sharing, lane-splitting, lane-filtering, white-lining, etc.,
in California is NOT against the law! 
Lane-sharing/splitting/filtering is very
common in Europe.

Copyright 2020, R. Fleischer

First, some minor clarifications:
Lane splitting, lane sharing, lane filtering or just filtering, and white-lining, are not thought of as the same thing around the world, or, even in the various States in the USA.  Late Splitting, as commonly used by motorcyclists in the USA means traffic may be stopped OR moving, and you ride your motorcycle in very heavy slower or not moving traffic, on the painted line (white-lining, in California), or, in some instances, perhaps nearly so, between adjacent lanes. This is typically done on Freeways, and very specifically is very common on California's major freeways.  Lane Sharing may or may not be specified by Departments of Motor Vehicles, but is typically mean to be that you are actually sharing one lane with another vehicle, which, although most often NOT explained further, typically means a car, but actually applies, usually, with another motorcycle.  In California, you are not supposed to be Lane Splitting or Lane Sharing, by weaving back and forth between lanes.  It is, however, very widely done.   Lane Filtering is typically used (words and how done) by folks going between long lines of STOPPED cars, and is more of a European use of the words and description.  In California, the meaning of all is, or can be, the same, but the meaning is specified.

"Lane Splitting" has been OK, that is, accepted in California, for many decades.  So long as done safely, the Highway Patrol was not concerned.   There was nothing "official" about the practice, at least as far as Laws, Rules, and Regulations were concerned.   The Highway Patrol recognized the need in very dense traffic situations.   Things haven't basically changed, except that we've had official guidelines, etc......and I have the updated information below.

Due to "politics" (REALLY!), the California Highway Patrol's own lane splitting article was removed from the State of California's government site (REALLY!).  However, "allowed" lane splitting was and is still in effect, and I have the information below, that was copied from the original California Highway Patrol's website.   This is still in effect, and likely to remain so.  I anticipate that at some date, the CHP website will again reflect things as they were.

On August 19th, 2016, the California Legislature passed AB 51, which formally defines lane splitting in the vehicle code, and explicitly authorizes the CHP develop educational guidelines relating to lane splitting in a manner that would ensure the safety of the motorcyclist and the drivers and passengers of the surrounding vehicles.

Also see:

In early 2013 the CHP had published its safety tips on its website, & motorcyclists hailed it as a breakthrough in traffic safety.  California was the only state in the country with sort-of-legal-lane-splitting, but state authorities had never, until then, told motorcyclists HOW to weave the white line safely.

"Really, it has been limited anarchy out there," said Sgt. Mark Pope, statewide motorcycle safety coordinator for the CHP, at the time. "Nobody has provided any guidance, so we decided it was time to figure that out." are some of the guidelines for motorcycle lane-splitting that were removed from the California Highway Patrol's website:

-- Travel no more than 10 mph faster than other traffic - danger increases at higher speed differentials.

-- It is not advisable to lane-split when traffic flow is at 30 mph or faster - danger increases as overall speed increases.

-- Typically, it is safer to split between the No. 1 and No. 2 lanes (the lanes farthest to the left) than between other lanes.

-- Consider the total environment in which you are splitting, including the width of the lanes, size of surrounding vehicles, as well as roadway, weather & lighting conditions.

-- Be alert and anticipate possible movements by other road users.

-- Don't put yourself in dangerous positions.

-- If you can't fit, don't split.

Source: California Highway Patrol

If you prefer to read the CHP document:

If you want to see the handout:   CHP, lane splitting (jpg)

Lane-splitting, a particular time-saver on such as Bay Area bridges & hundreds of other traffic choke-points, has been around almost as long as motorcycles. For decades it was necessary because bikes could overheat if they stopped moving. Newer motorcycles have more advanced cooling systems, but lane-splitting is still considered a safety tactic to prevent being rear-ended.  It is also true that overheating still happens regularly traffic in some areas of California cities is abominable during Rush Hours.

Filtering, as it is called in Europe, is very common.  Lane-splitting and Lane Filtering is legal in most areas of Europe and Asia. CAR DRIVERS EXPECT IT.

Actual safety data PROVES that properly done it is SAFER than NOT doing so!....yes, REALLY!!

One of the more detailed studies was done by the Safe Transportation Research & Education Center, at University of California at Berkeley.  It confirmed prior work done by various Agencies and groups.  Here is something to read:

There have been other studies regarding the safety of lane-splitting.

Lane splitting is not illegal in California.  You, as a lane-splitting motorcyclist, can be cited for unsafe practices, such as unsafe speed or unsafe lane changes ...but the California Highway Patrol is quite lenient, providing you are not egregiously being unsafe.  The California Highway Patrol allows it, without writing citations/tickets, if done safely. Some do it rather UNsafely, & do not obey the recommendations.  It is then up to the CHP, whether to ignore the rider ...or not.

As published in BMWMOA in the July 2015 issue:
"Keep in mind that it's impossible to have an informed opinion on lane splitting if you haven't spent three to six months doing it in California".

I would add, or, Europe, Asia, etc.    ...and...."Don't hate what you don't understand".

Is Snowbum "promoting" lane-splitting:  NO; just laying out the facts. Has Snowbum done it?  Yes, when he lived in Los Angeles, and when in some areas such as San Francisco area freeways, etc ...when traffic is very stop and go (little go, mostly stop).

10/03/2014.  Removed from URL article and moved to this new article.  Edit extensively due to CHP removing all the details, see the link.
05/04/2015:  Remove it is no longer on the CHP site.
05/31/2015:  Add the Berkeley study link.
03/06/2016:  Update meta-codes, layout.
06/14/2016:  Fix unlinked file to the CHP document. 
08/21/2016:  Update entire article:  metas, scripts, layout.  Fix extensive extraneous html code from area of copied CHP document.
02/18/2017:  Change article number.
01/19/2018:  Clean up layout, reduce excessive html, colors, fonts.  Clarify minor details. Add 10pxl margins.
01/09/2019:  Clarify definitions.  Add jpg of CHP handout.
01/09/2019:  Fix html title and also displayed title.

Copyright 2020, R. Fleischer

Return to Technical Articles List Page

Return to HomePage

Last check/edit: Monday, December 07, 2020