motorcycle lane splitting

Starting August 7, motorcyclists in Colorado will be permitted to engage in lane filtering, following the recent enactment of a new law by Governor Jared Polis. This law introduces a three-year trial period for this maneuver, which has been a topic of both interest and controversy among motorists. While some perceive lane filtering as “cutting to the front of the line,” it is regarded by experts as a method to enhance traffic flow. Below are the specifics of Colorado’s new motorcycle lane sharing law.

What the New Law Allows

Effective August 7, SB24-0749 authorizes motorcyclists in Colorado to overtake or pass another motor vehicle between two lanes of vehicles under the following conditions:

  • Stopped Vehicles: The motor vehicle being overtaken must be stationary.
  • Lane Width: The road must have lanes wide enough to safely accommodate the motorcycle.
  • Speed Limit: The motorcycle must be traveling at 15 mph or less.
  • Prudent Operation: Conditions must allow for the prudent operation of the motorcycle while overtaking or passing.

Restrictions on Lane Filtering

The law also sets clear boundaries on where and how lane filtering can be performed:

  • Right Shoulder: Motorcyclists are not allowed to overtake or pass on the right shoulder.
  • Farthest Right Lane: Passing to the right of a vehicle in the farthest right-hand lane is prohibited unless the highway is limited access.
  • Opposite Direction Traffic: Passing in a lane of traffic moving in the opposite direction is not permitted.

Lane Filtering vs. Lane Splitting

It is important to differentiate between lane filtering and lane splitting:

  • Lane Filtering: This occurs when a motorcyclist rides between stopped vehicles.
  • Lane Splitting: This happens when a motorcyclist rides between moving vehicles.

Three-Year Trial Period

The lane filtering law is temporary and will be in effect for a trial period ending on September 1, 2027. During this time, the Colorado Department of Transportation (CDOT) will collect and analyze safety data to evaluate the effectiveness and safety of lane filtering. This data will help determine whether the law should be made permanent, amended, or repealed.

Pros and Cons of Lane Sharing

Based on studies and expert opinions, here are some pros and cons of lane filtering and lane splitting:


  • Improves Traffic Flow: Enhances overall traffic movement by reducing congestion.
  • Safety: Lane-splitting motorcyclists are generally injured less frequently than those who do not lane split.
  • Reduces Rear-End Collisions: Helps in decreasing the number of rear-end collisions involving motorcyclists.


  • Driver Adjustment: The introduction of lane filtering requires vehicle drivers and motorcyclists to adjust, which could lead to an initial increase in collisions due to unaccustomed behavior. According to the Denver motorcycle accident attorneys at Dormer Harpring, sharing lanes is a common cause of accidents, which may be exacerbated by this new law.
  • Public Perception: According to a 2014 UC Berkeley survey, 61% of non-motorcycling public somewhat or strongly disapproved of lane splitting, and 36% of motorists mistakenly believed the practice was illegal. There is also a perception that lane sharing is unsafe and unfair.

Colorado’s new motorcycle lane sharing law represents a significant change in traffic regulation, aimed at improving traffic flow and safety for motorcyclists. The three-year trial period will provide valuable data to assess the impact of this maneuver on road safety and traffic dynamics. As the state embarks on this new initiative, both motorists and motorcyclists will need to adapt to the changes and ensure they adhere to the stipulated guidelines for safe lane filtering.

Leave a Reply

Your email address will not be published. Required fields are marked *