State has a Far Right as Practicable Requirement

A bicyclist riding slower than the normal speed of traffic must ride as close as practicable to the right-hand curb or edge of the roadway, except when passing, preparing for a left turn, avoiding a hazard (including a substandard-width lane too narow for a bicycle and vehicle to share safely), or approaching a place where a right turn is authorized.

Allows Two Abreast Riding

California has no statute that expressly permits or prohibits bicyclists riding two abreast. Because nothing in the Vehicle Code prohibits it, riding two abreast is generally understood to be lawful, subject to the requirement that a slower-moving bicyclist ride as near the right edge of the roadway as practicable and not impede the normal and reasonable flow of traffic.

Single File is Required

California does not have a statewide single-file-riding requirement for bicyclists. As with two-abreast riding, cyclists remain subject to the right-side-positioning and not-impeding-traffic rules that apply to all slower-moving roadway users.

Has a Safe Passing Law

Under the Three Feet for Safety Act, a driver overtaking a bicyclist proceeding in the same direction may not pass at a distance of less than three feet between any part of the vehicle and any part of the bicycle or its operator, and must change lanes to pass when another lane is available and it is safe to do so. If three feet of clearance is not possible, the driver must slow to a safe, prudent speed and may only pass when it would not endanger the bicyclist.

Helmets are required on the road

A person under 18 must wear an ASTM- or CPSC-certified bicycle helmet while operating or riding as a passenger on a bicycle. Separately, anyone operating or riding as a passenger on a Class 3 electric bicycle must wear a helmet regardless of age, and a person under 16 may not operate a Class 3 electric bicycle at all.

If Bike Lanes are present, they are required ( except when unsafe )

When a bicycle lane has been established under § 21207, a bicyclist traveling slower than the normal speed of traffic must ride within that lane, except when passing, preparing for a left turn, avoiding debris or a hazard, or approaching a place where a right turn is authorized.

Riders may use the sidewalks

State law does not itself regulate bicycles on sidewalks; § 21206 preserves the authority of a local authority to regulate, by ordinance, the parking and operation of bicycles on pedestrian or bicycle facilities. Whether sidewalk riding is allowed therefore depends on the city or county.

Does the Impeding Statute Apply to Bikes

A bicyclist, like any road user, may not travel at such a slow speed as to impede or block the normal and reasonable movement of traffic, unless reduced speed is necessary for safe operation. California separately recognizes a cyclist's right to occupy a full lane when a lane is too narrow to share safely with a passing vehicle.

Whether cyclists may treat stop signs as yield signs (the "Idaho stop").

California has not adopted an Idaho-style stop-as-yield law. Because a bicyclist has all the rights and is subject to all the provisions applicable to a vehicle driver under § 21200, a bicyclist must come to a full stop at a stop sign under § 22450, the same as a motor vehicle operator.

Restrictions exist on e-bikes and usage

California defines three classes of electric bicycle by motor type and top assisted speed (Class 1 and Class 3 pedal-assist up to 20 and 28 mph respectively; Class 2 throttle-assist up to 20 mph). A Class 3 electric bicycle may only be operated by a person at least 16 years old, and its speedometer and helmet requirements are set out in § 21213.

Allows the concept of Contributory Negligence that allows any contributory fault resuls in 'no fault'

California abolished the doctrine of contributory negligence in Li v. Yellow Cab Co. (1975) in favor of pure comparative negligence. A bicyclist may recover damages even if primarily at fault for a collision, with the recovery reduced in proportion to their own percentage of fault.