Dashcam video captures 100 to 150 teens riding bicycles on California’s State Route 120 near I-5

What the video shows and where it happened

A dashcam recording from San Joaquin County has captured a large group of teenagers riding bicycles in active traffic lanes on State Route 120 (the 120 Bypass) in the Manteca area, near the Interstate 5 corridor. In the video, a driver reports to 911 that roughly 100 to 150 youths are riding in the slow lane of eastbound SR-120, warning that a collision risk is imminent as vehicles approach at freeway speeds.

The footage has circulated widely online, prompting renewed attention on a pattern of large, loosely organized rides in and around Manteca that have at times shifted from local streets to high-speed roadways.

Public response and local safety concerns

Manteca’s mayor publicly addressed the incident, urging parents to intervene and stressing the potential for severe injury or death if bicyclists continue riding in freeway environments. Residents interviewed in local coverage described repeated encounters with large youth groups riding unpredictably and expressed concern that a single mistake by a rider or driver could trigger a multi-vehicle crash.

Separately, local reporting has described similar large gatherings—sometimes referred to locally as “ride outs”—that include riders performing wheelies and blocking multiple lanes on major city streets, adding to the hazards for motorists, pedestrians and the cyclists themselves.

What California law generally allows—and prohibits—on freeways

In California, bicycles are generally prohibited on freeways and expressways where state or local authorities have posted restrictions. State transportation policy also describes that limited freeway shoulder segments may be opened to bicyclists, typically in non-urban areas where alternative routes are not available, and those segments are managed through posted signs and local designations.

Officials in Manteca have emphasized that cycling on freeways is illegal in most circumstances and that enforcement decisions can depend on roadway designation and posted signage.

Enforcement tools under discussion in Manteca

Manteca has previously adopted a local ordinance aimed at addressing dangerous bicycle behavior in traffic. Following recent large group rides, the city has discussed changes to the municipal code intended to expand enforcement options—potentially including bicycle impoundments for certain violations and penalties for participation in organized or spontaneous “street takeover” activity involving bicycles.

• Large group rides can create sudden speed differentials and unpredictable lane movements on high-speed corridors.
• Local leaders are weighing additional enforcement tools, including temporary bicycle impoundment.
• California’s rules generally prohibit bicycles on freeways where restrictions are posted, with limited exceptions in designated segments.

In the dashcam audio, the caller warns that vehicles could collide with the group if officers do not arrive quickly.

What happens next

City officials and police have indicated that further steps may focus on a mix of enforcement and prevention, including identifying repeat behaviors, clarifying penalties, and encouraging parental involvement when riders are minors. For drivers, safety officials routinely advise slowing down, avoiding sudden maneuvers, and calling 911 when encountering riders or pedestrians in freeway lanes.