California E-Bike Injuries: What Families Should Save After a Crash

A new statewide study from UC San Diego reports a sharp rise in California traffic collisions involving electric bicycles. Children were disproportionately represented among injured e-bike riders, and moderate-to-severe injuries were more common than among riders of traditional bicycles.

The study gives families a reason to take e-bike crashes seriously. It does not prove that an e-bike manufacturer, driver, rider, school, city, or property owner was legally responsible for any particular collision. That depends on what happened and what the evidence shows.

When a child or adult is seriously hurt, the e-bike itself may be only one part of the investigation. Vehicle data, roadway conditions, camera footage, controller settings, repair records, medical documentation, and the bike's legal classification may all matter.

Important: This article provides general information, not legal advice. The UC San Diego study describes statewide collision patterns; it does not establish fault in an individual crash. Every injury claim depends on its own facts. Contacting Wildeboer Legal does not create an attorney-client relationship unless a written agreement is signed.

What the California Study Found

UC San Diego researchers analyzed California Highway Patrol collision data from 2018 through 2024. The dataset included 4,035 e-bike collisions and 58,332 traditional bicycle collisions.

The university reported that:

• reported e-bike collisions increased from 2 in 2018 to 1,506 in 2024;
• riders age 14 or younger made up 15.6% of injured e-bike riders, compared with 10.2% of injured traditional bicyclists;
• moderate-to-severe injuries were more common among e-bike riders;
• overall mortality rates were similar during the full study period, although researchers observed an increase in e-bike-related deaths in 2024;
• and injured e-bike riders had low rates of helmet use.

Those numbers need context. E-bike ownership and use expanded during the study period, and early collision reporting may not have identified e-bikes consistently. The study shows a serious and growing public-safety problem. It does not mean every e-bike is defective or that every crash has the same cause.

An E-Bike Crash May Have More Than One Evidence Path

After a serious collision, the investigation should not stop at “the rider fell” or “the driver says the rider came out of nowhere.” Depending on the facts, it may need to examine:

• whether a driver failed to see or yield to the rider;
• whether speed, distraction, impairment, an unsafe turn, or a door opening contributed;
• whether the bike's brakes, wheel, frame, throttle, controller, battery, or software malfunctioned;
• whether assembly, maintenance, repair, or modification changed the bike;
• whether a dangerous intersection, broken pavement, poor lighting, construction zone, blocked sightline, or missing sign contributed;
• and whether the rider's age, helmet use, conduct, and e-bike classification are relevant.

These are investigation questions, not conclusions. Several factors and several parties may be involved in the same crash.

Preserve the E-Bike Before It Is Repaired, Returned, or Discarded

The actual bike may contain evidence that photographs cannot replace. After a serious injury, do not authorize a repair, return, trade-in, destructive test, or disposal until you understand whether the bike should be preserved.

If it is safe to do so, save or document:

• the complete e-bike and every detached or broken part;
• the battery, charger, display, controller, keys, and accessories;
• the serial number, model number, class label, motor wattage, and listed assisted speed;
• close photographs of the frame, wheels, brakes, fork, drivetrain, throttle, wiring, battery connections, and damage;
• the purchase receipt, online order confirmation, and screenshots of the original product listing;
• manuals, warnings, packaging, assembly instructions, and warranty documents;
• repair, tune-up, tire, brake, and modification records;
• communications with the seller, manufacturer, bike shop, repair person, or marketplace;
• and app, GPS, ride-history, firmware, controller-setting, or connected-device data.

Do not ride or charge a visibly damaged e-bike or lithium-ion battery merely to test it. Fire and electrical hazards require safe handling. Evidence preservation never requires putting someone in danger.

If a shop or insurer takes possession of the bike, record who received it, when, where it will be stored, and what work was authorized. Ask that no repairs or destructive inspection occur without notice.

Save Crash-Scene and Vehicle Evidence Quickly

Video and electronic records can disappear much faster than the physical bike.

Families should try to preserve:

• the police or CHP collision report number;
• names and contact information for witnesses;
• photos and video of the bike, vehicle, debris, marks, intersection, bike lane, signs, signals, lighting, and sightlines;
• nearby business, apartment, school, bus, doorbell, traffic, and security-camera locations;
• dashcam or in-vehicle video;
• the driver's name, insurance, license plate, employer, and vehicle information;
• the rider's phone location, fitness tracker, navigation, and ride-app data;
• tow-yard, storage, and property-release records;
• and a written timeline while memories are still fresh.

Do not trespass or interfere with police work to gather evidence. Identify possible cameras and records promptly so appropriate preservation requests can be considered before routine deletion.

If a public road, traffic device, school property, transit vehicle, or government employee may be involved, special claim procedures and shorter deadlines may apply. Identifying the correct entities early can matter.

Medical and School Records Can Show the Real Impact

E-bike crashes can cause head injuries, fractures, dental damage, road rash, internal injuries, and lasting emotional symptoms. Accurate follow-up matters both medically and evidentially.

Save:

• records from ambulance services, emergency rooms, urgent care, imaging facilities, medical providers, surgeons, and therapists;
• discharge instructions and medication information;
• photographs showing injuries as they change;
• the damaged helmet, clothing, shoes, backpack, phone, and eyewear;
• medical bills and insurance explanations of benefits;
• school absence, accommodation, tutoring, activity-restriction, and grade-impact records;
• work-loss records for an injured adult or a parent providing care;
• and notes describing headaches, dizziness, memory problems, sleep changes, pain, mobility limits, anxiety, or difficulty returning to school and normal activities.

Do not exaggerate symptoms. Do not dismiss them because the rider stood up after the crash. Consistent medical care and accurate records are more useful than dramatic language.

California E-Bike Class and Helmet Rules May Matter

California Vehicle Code section 312.5 defines three e-bike classes. In general, Class 1 pedal assistance stops at 20 mph, Class 2 throttle assistance stops at 20 mph, and Class 3 pedal assistance stops at 28 mph. California's definition also limits an electric bicycle motor to 750 watts and requires a classification label on bikes manufactured or distributed under the statute.

California Vehicle Code section 21212 requires riders under 18 to wear an approved, properly fitted and fastened bicycle helmet on public streets, bikeways, paths, and trails. Section 21213 prohibits a person under 16 from operating a Class 3 e-bike and requires a helmet for any Class 3 operator or passenger covered by that section.

A bike modified beyond statutory power or speed limits may not qualify as an electric bicycle under California law. Preserve evidence of the bike's original configuration and any later changes.

A possible traffic or helmet violation does not, by itself, decide civil responsibility or erase another party's negligence. It is one fact among many. The investigation still needs to examine the driver, roadway, product, repair history, warnings, injuries, and sequence of events.

Sources

• UC San Diego: UC San Diego Study Finds an Exponential Increase in E-Bike Injuries in California
• Trauma Surgery & Acute Care Open: An Exponential Increase in E-Bike Injuries in California
• California Vehicle Code section 312.5: Electric-bicycle definitions and classifications
• California Vehicle Code section 21212: Helmet requirements for riders under 18
• California Vehicle Code section 21213: Class 3 age and helmet requirements

The Bottom Line

After a serious California e-bike crash, preserve more than a few phone photos. Save the bike and its electronic data, purchase and repair records, scene and camera information, vehicle details, the helmet and damaged property, and complete medical and school documentation.

Wildeboer Legal helps injured riders and families in Southern California evaluate e-bike crashes, motor-vehicle collisions, possible product defects, unsafe-roadway questions, and urgent evidence-preservation needs. If you or your child was seriously injured in an e-bike crash, contact Wildeboer Legal for a free consultation about the specific facts.

Call or text (562) 608-8887 or contact Wildeboer Legal online for a free consultation.

Se habla español. Farsi assistance is also available.

No outcome is promised, and contacting the firm does not create an attorney-client relationship unless a written agreement is signed.