There is so much information out there about e-bikes it can be overwhelming, so HBL has boiled it down to the hottest topics for Hawai‘i. This page covers:
An e-bike (or electric bike) can look a lot like a traditional bicycle except an e-bike is with an electric motor and rechargeable battery to provide the rider a power boost for climbing hills or traveling long distances. Some e-bikes provide assistance only when the rider is pedaling, while others have throttles and assist regardless of whether or not the pedals are being turned.
Currently, Hawai‘i legally recognizes e-bikes as “low-speed electric bicycles,” as defined under title 15 United States Code section 2085 which clarifies the the term “low-speed electric bicycle” to mean:
E-bikes can make riding a bicycle for fun, commuting, and transportation easier and more convenient; and allow current bicycle users to bike more often and farther. The electric motor makes pedaling easier so folks can ride with less effort, helping people:
including but not limited to streets, highways, roadways, shoulders, bicycle lanes, bikeways, and bicycle or multi-use paths. E-bikes have the capability to move people faster than traditional bicycles, so e-bike riders need to use caution, especially on trails or areas where drivers may not expect a bicycle rider to be moving as fast.
BATTERY – Modern electric bike batteries are typically made with lithium-ion technology, which has a high energy density, lightweight nature, and reliable performance. The capacity of the battery is measured in watt-hours (Wh) and determines the range on a single charge.
E-bike batteries can be positioned on the down tube, on the rear rack, or integrated inside the down tube. Bikes with batteries hidden inside the frame look sleek and modern, but typically cost a bit more.
CONTROLLER – The controller is the electronic brains of the e-bike, it monitors speed, acceleration, power, battery voltage, pedal activity, pedal assist, etc. It interprets rider inputs and regulates motor performance to ensure safe smooth power delivery.
E-bikes are normally outfitted with a handlebar mounted digital display, basically a mini dashboard. The display is where the rider will see important system information relayed from the controller like battery status, speed, pedal assist modes, etc.
MOTOR – The motor is the component that spins the wheels.
The motor is compact and can be built into the hub of the back or front wheel, or mounted in the center of the bike.
SENSOR – The sensors on an electric bike are the main way the motor communicates with the rest of the components. The sensors analyze the rider’s pedaling input, which activates the motor and provides assistance.
The two main types of e-bike sensors are cadence and torque sensors. Basically, a speed or cadence sensor detects if you’re pedaling, and a torque sensor measures how hard you’re pedaling.
THROTTLE – In addition to the motor being activated by pedaling, some e-bikes are also equipped with a throttle that allows the rider to operate the motor without pedaling at all.
The throttle is located on the handlebars and can be twist grip or thumb operated.
In the US, a legal e-bike must have operable pedals, meaning you can pedal it with or without any motor assistance, and a motor with no more than 750 watts of power. Electric bikes are categorized into three e-bike classes based on three main criteria: top speed, type of assistance, and motor power. These classes are:
The motor requires the rider to pedal in order to provide power (there is NO throttle), and the motor stops providing assistance when the e-bike reaches 20 mph.
An e-bike similar to Class 1 e-bikes (has a pedal-assist mode up to 20 mph); but in addition they also offer a throttle-powered mode that doesn’t require pedaling.
Also called a “speed pedelec”, this vehicle has a motor that ceases to provide assistance when the e-bike reaches 28 mph. Must have a speedometer, and may or may not have a throttle.
Any vehicle that does NOT fit into the three class definitions falls into the “Unclassified” category & may not be legally considered an e-bike.
Example of Class 1:
Example of Class 2:
Example of Class 3:
In Hawai‘i, if it goes faster than 20mph (with the rider not having to pedal), is equipped with a motor more than 750 Watts, or it does not have operable pedals, it is NOT legally considered an e-bike and should only be operated on private lands where you have permission.
Most e-bikes offer different levels of pedal-assistance from the motor, called “modes” or “drive modes.” These modes can be selected using a handlebar-mounted switch and are usually visible on a handlebar-mounted display.
» Common names for these modes are Eco, Standard / Trail, and Boost / Turbo. Eco mode reduces the level of pedal assistance and increases battery life. Boost / Turbo mode increases the level of pedal assistance to improve acceleration but reduces battery life.
Pedal assist is an operating mode on an e-bike that engages the motor to deliver power to help you pedal easier and go faster. With pedal assist, the motor engages only when the pedals are being rotated (the rider must pedal to get power).
Power is the amount of work that can be done by the e-bike motor. It can be thought of as a torque multiplied by RPM (i.e., pedaling cadence).
Range is the distance or time a battery will last. Range is primarily determined by battery capacity (Wh), but it’s also affected by the total weight of the bike and rider, the terrain (hilly vs. flat), and the drive mode (Eco vs. Boost).
For e-bikes, torque refers to the maximum force the motor can apply to turn the rear wheel. Measured in newton meters (N m), torque is a turning force that causes rotation (i.e., rotating the rear wheel.).
» Torque is a spec to check if you plan to ride a lot of hills and/or haul heavy loads. Your actual riding torque will vary, though, as you change your pedal-assist settings.
E-bikes on the surface may look almost undistinguishable from your standard bicycle, but the added weight and extra power from the battery means the rider needs to ramp up their riding awareness or risk causing injury to themselves & other roadway users. You should use caution when traveling faster than a speed you normally would, especially on trails or areas where motor vehicles may not expect you to be moving as fast. Your safety and the perception of bicyclists depend on you.
Things to keep in mind when riding on the street with cars:
Things to keep in mind when using bike infrastructure:
Here’s a quick recap of answers to the most common questions asked about electric bikes in Hawai‘i.
In Hawai‘i, you must be at least 15 years old to legally ride an e-bike.
You are required to register your e-bike to operate it on public roadways. It costs $30 (one-time fee) to register an e-bike. More info on bicycle registration here.
E-bikes are allowed on any roadway, lane, or path that traditional bicycles are allowed on, including shared-use paths.
E-bikes that are Class 2 have a throttle feature which the rider could use to engage the motor without pedaling. If the e-bike does not have a throttle, the rider must pedal to activate the boost from the motor.
A properly fastened helmet is required when bicycling for riders under 16 years of age.
If the motor goes faster than 20 mph, Hawai‘i doesn’t consider it an “e-bike”, and therefore cannot be registered to ride on public streets. Note: the motor will cease providing assistance at it’s “top assisted speed”, but the rider can keep pedaling faster to make the e-bike go faster.
Driver’s license and insurance is not required.
These vehicles are NOT the same as e-bikes because they have motors that make them capable of going over 20 mph, are more than 750 watts (1 hp), and do not have pedals that function.