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Motorcycle Lane Filtering in Montana? What you should know.

Montana Senat Bill 9 was passed allows the operator of a two-wheeled motorcycle to overtake stopped or slow-moving vehicles at a speed not in excess of 20 mph, to filter between lanes of stopped traffic traveling in the same direction as conditions permit, and specifies reasonable and prudent motorcycle operation while lane filtering.

A motorcyclist is riding the dividing line next to a line of slow moving or stopped cars in traffic.
Lane Filtering through traffic

Well, that sounds completely crazy. Why would such a law pass?

Great question. According to the American Motorcycle Association, Lane Filtering or Lane Splitting has had long-term success in California, and the University of California study by Berkley researchers showing that it enhances motorcycle safety. "A motorcycle's narrow width can allow it to pass between lanes of stopped or slow-moving cars on roadways where the lanes are wide enough to offer an adequate gap. This option can provide an escape route for motorcyclists who would otherwise be trapped or struck from behind. There is evidence (Hurt, 1981) that traveling between lanes of stopped or slow-moving cars (i.e., lane splitting) on multiple-lane roads (such as interstate highways) slightly reduces crash frequency compared with staying within the lane and moving with other traffic."

Here's an article from titled "Why Do Motorcycles Lane Split" but do take note that the law here in Montana is different than Califorina and Utah.

Four thing to consider as a driver of a car or truck with regards to Lane Filtering:

Help a motorcyclist out by paying attention to what is going on around you, especially in congested stop-and-go traffic. Watch your mirrors and allow someone the opportunity to merge in front of you if needed. Look at it as you are helping to protect the riders like you are a part of their defensive line. The riders will appreciate you and your help.

Please avoid using your phone. Distracted driving is by far more dangerous to you, and the motorcyclist than lane-filtering will ever be. Distraction-free driving is safer for everyone. Visit our page on Distracted Driving to learn more. #IDontDUIT - (I Don't Drive Under the Influence of Technology)

Always Drive Sober. Choosing to only drive sober without exception is a real lifesaver for yourself, other vehicles and especially motorcyclist. As of March 1, 2021, over 50% of the 31 roadway fatalities on Montana's roadways have involved an impaired driver this year.

Lane Filtering is purely a safety thing for the motorcyclist. Being caught in congested traffic is one of the most dangerous situations for a motorcyclist. A small rear-end fender bender in stop-and-go traffic might scratch your bumper but that same impact could kill someone on a motorbike.

You will likely be surprised the first couple of times you unexpectedly see a motorcycle ride past your driver's window when you are stopped in traffic. Don't worry; motorcyclists aren't trying to jump ahead and get to the front of the line; they are trying to get out of the way and assist with the overall flow of traffic so you can get through it all faster.

Where did this come from?

In many countries, lane filtering and lane splitting on a motorcycle is very much a normal and expected part of traffic flow. Drivers of conventional vehicles expect a motorcyclist to move to the front of the line. It gets them out of the way, and you get to move forward and take the spots they would otherwise be taking. When the motorcyclist moves between the cars, they are safer because they become protected by the big chunks of metal (cars and trucks) surrounding them on all sides.

I don't know if I like this?

That can be understandable. Here in the US, whenever we get in line, we are taught to "Wait Your Trun" It may seem like the motorcyclist is cheating the system by jumping to the front of the line. Trust that Lane Filtering and Lane Splitting's practice is backed by data and evidence (Hurt, 1981). It's safer for the motorcyclist and will help cut down on traffic congestion which will help you get to where you are going sooner.

Will there be mass hysteria out there on our roads with biker gangs swarming our vehicles at every stoplight?

Not at all. There are motorcyclists who might not feel comfortable lane filtering, and other motorcyclist may oppose the practice all together. Keep in mind that the flow of traffic must be below 10 miles an hour and the motorcyclist can not lane-filter at a speed above 20 miles per hour. Additionally, Montana Senate Bill 9 allows for, but does not require a motorcyclist to lane-filter.

Here is the exact language from the bill that was passed but does not take effect until October 1, 2021.

Lane filtering for motorcycles.
(1) An operator of a two-wheeled motorcycle may engage in lane filtering when: (a) the operator of a two-wheeled motorcycle is on a road with lanes wide enough to pass safely; (b) the overtaking motorcycle is not operated at a speed in excess of 20 miles an hour when overtaking the stopped or slow-moving vehicle; and (c) conditions permit continued reasonable and prudent operation of the motorcycle while lane filtering.
(2) As used in this section, "lane filtering" means the act of overtaking and passing another vehicle that is stopped or traveling at a speed not in excess of 10 miles an hour in the same direction of travel and in the same lane.
The bill, sponsored by state Sen. Russ Tempel (R-SD14) and state Rep. Barry Usher (R-HD40), was signed by Gov. Gianforte on March 2, 2021

We aren't alone here. Montana joins Utah and California in allowing lane-filtering/splitting.

To view the full position statement from the American Motorcycle Association on lane filtering and Lane Splitting, click here:

With that, thank you and, Drive Safe Missoula

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