Bike lanes, Class I to IV
California sorts bikeways into four classes. They are not equal. Separation from fast traffic matters most.
This page is a draft. Every fact links to its source, so you can check it yourself.
The four classes
California law sorts bikeways into four classes. (Streets and Highways Code 890.4)
| Class | Name | What it is |
|---|---|---|
| I | Bike path or shared use path | Its own path, away from cars, shared by people biking and walking. |
| II | Bike lane | A painted lane on the road just for bikes. Cars may cross it to park or turn. |
| III | Bike route | Signs or painted arrows ("sharrows") on a road you share with cars. No space of your own. |
| IV | Separated bikeway or cycle track | A bike-only lane next to the road with something physical between you and cars, like posts, curbs, raised pavement or parked cars. |
A Class II lane on a 25 mph street can feel fine. The same paint next to 45 mph traffic is a very different ride.
Why separation matters
- FHWA says nearly one third of fatal and serious bike crashes away from intersections happen when a driver is passing the rider. (FHWA)
- Adding bike lanes can cut total crashes by up to 49% on urban four-lane undivided roads and up to 30% on two-lane roads. (FHWA)
- Upgrading a painted lane to a separated lane with posts can cut bike-car crashes by up to 53%. (FHWA)
The local picture
- Among US cities over 500,000 people, Sacramento had the second-highest bicyclist death rate in 2024 (1.12 per 100,000), behind only Tucson. The national average was 0.32. (NHTSA, 2024 Bicyclists fact sheet)
- In 2023 Sacramento County ranked 4th worst of 58 California counties for people killed or hurt in bike crashes. (California Office of Traffic Safety)
- Nationwide, 1,103 people on bikes were killed in 2024. (NHTSA)
E-bikes and young riders
- In California, police-reported e-bike injury crashes rose from 2 in 2018 to 1,566 in 2024. Injured e-bike riders were more often 14 or younger than regular bike riders (15.6% vs 10.2%). Part of that rise is simply more e-bikes on the road. (Austin and others, 2026)
- E-bike classes: Class 1 and 2 help up to 20 mph. Class 3 helps up to 28 mph and riders must be 16 or older. Anyone under 18 must wear a helmet. (Sacramento County)
- Class 3 e-bikes are not allowed on county regional park trails, including the American River Parkway and Dry Creek Parkway. (Sacramento County)
- In the City of Sacramento, e-bikes may ride anywhere regular bikes can, including city bike lanes and shared-use paths. (City of Sacramento)
- A two-wheeler with no pedals or more than 750 W or faster than 28 mph is not an e-bike. It is a motor vehicle. (City of Sacramento)
More kids riding faster bikes is one more reason to separate bikes from fast car traffic.
A note on crash data
Police crash reports record fault from the officer's point of view. Many bike crashes are coded as "wrong way" riding. That can be true, and it can also mean a rider was avoiding a road with no safe space. StreetCase shows the codes as recorded and points this out.
What to ask for
- "Please upgrade the Class II lane on [road] to a Class IV separated lane with posts."
- "Please add bike lanes on [road] when it is next repaved."
- "Please close the gap in the bike network between [A] and [B]."
Sources for this page
- Streets and Highways Code section 890.4, California Legislature, 2015
- Bicycle Lanes (FHWA-SA-21-051), Federal Highway Administration, 2021
- Traffic Safety Facts, 2024 Data: Bicyclists and Other Cyclists (DOT HS 813 822), National Highway Traffic Safety Administration (FARS), 2026
- OTS Crash Rankings: Sacramento County, 2023, California Office of Traffic Safety, 2023
- An exponential increase in e-bike injuries in California, Trauma Surgery & Acute Care Open (BMJ), 2026
- Back-to-School Season Brings More Young Riders to Local Trails: Know Your E-Bike Before You Ride, County of Sacramento, 2026
- E-Bike Safety and Law, City of Sacramento, 2026
Last checked 2026-11-02.