New rules heavily restrict the types of bikes Caltrain users can bring on board, and baby seats are now no longer allowed

Caltrain will start banning cargo bikes and any bike that doesn't conform to the railroad's required dimensions.

"Caltrain’s bike cars are designed to carry 36 bikes safely and efficiently (four bikes per rack)," states the Caltrain bike rules page. "Oversized bikes are not allowed onboard to maximize the number of riders with bikes on board."

"While crowded bike trains have been an issue as Caltrain has increased its ridership, the core problem is that they haven't allotted enough space on their updated fleet of trains to accommodate an appropriate volume of people riding bikes," wrote the San Francisco Bicycle Coalition's Christopher White.

"An outright ban on family bikes is too extreme. While commute period trains can get crowded, mid-day and weekend trains are not," wrote Shirley Johnson, who helped found the advocacy group BIKES ONBoard.

https://sf.streetsblog.org/2026/03/04/as-bike-cars-overflow-caltrain-bans-large-bikes-and-panniers