The latter is what has just become legal (well, almost) in Arizona, making it the fourth state to now legalize some form of lane filtering, after California, Utah and Montana. While it's (almost) legal, it's still only allowed under very specific conditions.
The first rule to know is that it's only allowed on roadways with speed limits of 45 and less. It's never allowed on freeways. Which means that only surface streets are open for filtering. This speed allows for proper reaction time in the case of any unanticipated behavior from other motorists, road debris, etc.
The second rule is that the road must have 2 or more adjacent traffic lanes in the same direction of travel. This means that a single lane road is off limits. A double lane road where one is a turning lane and one goes straight is also off limits. 2 of the lanes must be in the same direction of travel.
Third rule is that motorcycles can only filter between STOPPED vehicles. So first, you must wait for the vehicles ahead of you to be at a complete stop and then you can proceed to filter to the front.
Fourth rule is that your speed may not exceed 15mph when filtering. Since cars will already be stopped and you'll be moving closely between them, it's going to be in everyone's best interest and create the safest operation when done at this reasonable speed. Anything faster opens you up to become victim of unanticipated events.
Finally, the movement may be made safely. Now, this one leaves a lot open to subjectivity, but it seems pretty obvious. Wheeling down the middle of the lanes isn't gonna win you any points with anyone except the license division. If there's a big pothole on the line, that may present a hazard and cause your bike to lose control and go into the side of a car. This final one can be boiled down to, "Don't be stupid." This is a privilege and abuse of it will take us, as a community, steps backwards. If this proves efficacious in reducing deaths and easing congestion, who knows, maybe we'll see this get passed for at-speed lane splitting as well.
You can watch it by clicking here. In the video, we see a motorcycle rider lane filtering shortly after the act became legal in the state of Utah. As he gets to the front of the traffic line, a Pizza Hut delivery driver opens his car door in the path of the motorcycle saying, "Hey, you should go stay in the lane." The motorcyclist spends the next few seconds educating him, sternly but not harshly, about it being a new law. The driver, too proud to admit he was wrong puts on a toothy smile and keeps the door open, blocking his path, until the green light comes and traffic begins to move again.
If you're riding in a state that has recently introduced lane filtering, then you can probably expect some unpleasant reactions from some uninformed motorists. This is why we highly encourage you to check out our action camera helmet chin mounts and record every ride. Mounted to your bike, you're not going to see anything but where the camera's pointed, unless it's a 360º camera. If you mount it to your chin, your camera sees what you see! Our FLEX Slim chin mount is the best chin mount for any helmet. It's completely bendable and flexible to any helmet shape so every mount is custom shaped to your helmet. Grab a chin mount and an action camera. Make sure to record your rides and protect yourself.
Got a question about filtering that you're unsure about? Drop it in the comments and maybe someone will have the answer!