eBike Glossary of Terms

I’m going to continue to grow this glossary and link to more in-depth articles as this website grows.

AC Current – or alternating current, is used in electrical systems, but is not often used in light electric vehicles (LEVs).

Advanced Battery – An advanced battery is a type of battery that uses NiMH or lithium cells and typically requires a battery management system (BMS) for optimal performance.

After Market Kit – An after market kit is a set of components that can be used to convert a manual bicycle into an electric bicycle.

Amp – The term “amp” refers to the unit of electrical current known as the ampere, which measures the flow of electricity over time.

Amp Hours or AH – is a unit of energy equal to the amount of electricity that flows through a given point in one hour.

Auxiliary Battery – An auxiliary battery is an optional, extra battery that can be used to power a vehicle.

Maintaining an eBike Battery for the longest life
Maintaining an eBike Battery for the longest life

Battery, or Energy Storage Device – is made up of cells that create a specific voltage and current to power an electric motor or vehicle. I’ve got an article talking about what to do when your battery is dead. 👉 eBike Battery Dead Here’s What To Do

Battery Box, or Battery Package – also known as a battery package, is the combination of cells that make up a battery and provide electrical energy for a vehicle.

Battery range – The range of a battery depends on various factors including its charge status, capacity, and various environmental factors.

Battery capacity (Wh) – The capacity of a battery is measured in watt-hours (Wh), and the higher the watt-hour rating, the longer the range. You’ll find anything from a basic 250 Wh battery to powerful 1,000 Wh double-battery solutions. As a general rule, the higher the watt-hour rating of a battery, the higher its range. The weight of the battery is proportional to its capacity.

Battery Cradle – A battery cradle is a support for a battery.

Bottom Bracket – A bike bottom bracket is a part of the bike frame that holds the bicycle crank (pedals and arms) and bearings. It is often called the “BB” it usually a round shell with threads to hold the crank cartridge. Another term used is the “bottom bracket shell” which defines the circular frame component. Read about measuring a bottom bracket for ebike conversion in this article. 👉 How to Measure a Bottom Bracket for a Mid-Drive eBike Conversion

Bottom Bracket Motor – A bottom bracket motor, also known as a central motor or mid-motor, is a motor located near or around the bottom bracket or pedal axle of a bicycle.

BMS in an eBike Battery
BMS in an eBike Battery

BMS– A battery management system (BMS) is an electronic circuit found on advanced batteries that helps protect the battery and prevent overheating and other safety issues, and monitors the state of charge. Read more about how important the BMS is on your eBike in this article. 👉 What is the BMS on an eBike Battery and How Does it Work?

Wired eBike Taillight
Wired eBike Taillight

Brake Light – A brake light and taillight is a light that is activated when the brakes are applied. Read more about taillights for ebikes 👉 Ebike Taillights and Options

How does an eBike brake sensor work
How does an eBike brake sensor work

Brake Sensor – A brake sensor is a device that turns off the motor when the user applies the brake lever. I’ve got a complete guide to this component 👉 What are eBike Brake Sensors and How Do They Work

Brushless DC Motor – A brushless DC motor, also known as a BLDC motor, is a type of motor that has no wear points other than the bearings, making it longer lasting and simpler than a brush-type motor. However, it requires more expensive control electronics. Ref. BMS above

Brush Type DC Motor – A brush-type DC motor, on the other hand, uses brushes in the motor, creating a wear point but requiring less expensive control electronics and being less expensive to manufacture.

Battery cells in an eBike battery
Battery cells in an eBike battery

Cells – Cells are individual electrochemical devices that produce electric current and are combined into batteries to provide the appropriate voltage and current for a specific purpose. The quality of the cells is important for battery life and discharge rates

Ceramic Magnets – Ceramic magnets are used in electric motors and are lower in performance and cost compared to neodymium magnets.

Charger – A charger is a device used to restore the charge to a battery.

Connectors – Connectors are fittings that allow electrical components and wiring to be connected, and are often easily unplugged or released.

Crank Arms – Crank arms are the parts of a bicycle’s pedals that connect to the pedals and allow the pedals to rotate.

Current – Current refers to the flow of electricity, and is often used to describe the amount of electrical energy being used by a vehicle.

DC – or direct current, is the form of electrical current used in most light electric vehicles (bikes)

DC Motor – A DC motor is a motor that uses direct current.

Direct Drive Motor – A direct drive motor is a type of hub motor that has no gear reduction, making it simpler and quieter but also larger and more expensive than gear-type motors.

eBike Display
eBike Display

Display – A display is a device used to show various types of information, such as speed and battery level.

DIY Kit – A DIY kit is a set of components that can be used to convert a manual bicycle into an electric bicycle.

Dropper Seatpost –A dropper seatpost is a type of seatpost that can be adjusted in height using a remote on the handlebar.

Ebike – An ebike is a generic term for an electric-powered bicycle, but can also refer to a specific type of electric bike with specific features. (See Pedelec) I’ve got a fun article describing 👉 What Does it Feel Like to Ride an eBike

eBike or electric bike
eBike or electric bike

Electric Bicycle – An electric bicycle is a type of bicycle that is legally considered a “bicycle” in many places, but is equipped with an electric motor and battery to assist the rider.

Electric Bike Mode – The electric bike mode is a level of motorized support provided by a pedal-assist electric mountain bike (E-MTB), which can be selected by the rider using a switch on the handlebars and displayed on a unit mounted on the handlebars. The Shimano STEPS E8000, for example, offers three drive modes: Eco, Trail, and Boost.

EPAC – An EPAC, or electric pedal-assist cycle, is what European Union law considers an electric bike.

Ebike Shift Sensor Picture and Location
Ebike Shift Sensor

Gear Shift Sensor – A gear shift sensor is a device that detects when the gears on a bicycle are shifted and sends a signal to the motor controller to adjust the motor’s performance accordingly. I’ve got a complete article about shift sensors read it 👉 What is an eBike Shift Sensor and How Does It Work

Gear Type Motor – A gear-type motor is typically a hub motor that uses a gear reduction inside the hub shell. These motors are generally less expensive but can be noisy and have more wear points.

Hall Sensor – A hall sensor is a type of sensor that uses a magnetic field to detect the position or speed of an object.

eBike Headlight
eBike Headlight

Headlight – A headlight is a light mounted on the front of a vehicle that is used for illumination when driving at night. Read more about eBike Headlights in this article 👉 eBike Headlights Wiring and Options

A hub motor for an eBike is located in the center of the wheel
A hub motor for an eBike is located in the center of the wheel

Hub Motor – A hub motor is an electric motor located in the front or rear hub of a bicycle wheel. Get a more indepth definition in this article. 👉 What is a Hub Motor on an eBike

Human Electric Hybrid – A human electric hybrid is an electric bicycle that allows both human and electric power to be used to propel the vehicle.

ICE – An internal combustion engine, or ICE, is a type of propulsion device found in gas-powered vehicles.

Lead Acid Batteries – Lead acid batteries are a type of battery that uses an older technology and are relatively inexpensive, but are heavy, reliable, and have good discharge and charge capabilities. They are also nearly 100% recyclable.

LEV – stands for “light electric vehicle,” which refers to small, lightweight electric vehicles such as electric bikes, electric scooters, and electric skateboards.

Low-Speed Electric Assisted Bicycle – A low-speed electric-assisted bicycle is what United States law considers an electric bike.

Lithium Battery – Lithium batteries are a type of advanced battery that have excellent performance, weight, and lifespan characteristics, but come in several different types such as lithium manganese and lithium iron phosphate. All lithium batteries are flammable and require a BMS and careful handling to reduce the risk of fires, which are actually very rare despite their media attention.

Max Discharge or Max current – The max discharge or max current refers to the rate at which a battery can be discharged.

Manual Bicycle – A manual bicycle is a type of bicycle that is propelled solely by human power.

Mid-drive motor on a bike
Mid-drive motor on a bike

Mid-Drive Motor – A mid-drive motor, also known as a bottom bracket motor, is a motor located in the bottom bracket of a bicycle, as opposed to in the hub. This type of motor is becoming popular on E-MTBs because it provides a low, centered weight distribution, intuitive ride feel, and easy wheel removal compared to hub motors. I’ve got a complete article about mid-drives, check it out 👉 What is a Mid-Drive Motor eBike

eBike Controller
eBike Controller

Motor Controller – A motor controller is an electronic circuit that controls the speed of an electric motor and may also control other functions depending on the model and features of the vehicle. I like to think of the motor controller as the “brains” of the electrical system on your eBike. Many newer eBikes actually have the ability to program the controller to your personal preferences.

Motor – A motor is an electric motor that assists the rider and can be located in various places on the bike.

Pb or Pb Batteries – A batteries refer to lead acid batteries.

Neodymium – Neodymium is a rare earth metal used to make high-energy permanent magnets that are often found in LEV motors and are a significant cost.

Ni Cad – Ni Cad batteries, or nickel cadmium batteries, are no longer commonly used in electric bikes, but may be found on some older models. They are toxic and have lower performance than NiMH and lithium batteries.

NiMH Battery – or nickel metal hydride batteries, are nontoxic and have higher performance than lead acid batteries but lower performance than lithium batteries. They are not common in electric bikes but can be found in some models

PAS Sensor – A PAS sensor is a device that detects the pedaling speed and cadence of a bicycle and sends a signal to the motor controller to adjust the motor’s performance accordingly.

Pedal Assist System on eBike
Pedal Assist System on eBike

PAS Bike – A PAS bike is a bicycle with a Pedal Assist System, which is typically designed for the Japanese market and delivers additional power to the motor based on the rider’s effort. PAS is a Yamaha patent. Read more about pedal assist systems in this article 👉 What is Pedal Assist and How Does it Work

Pedelec – A pedelec is an electric bicycle that requires the rider to pedal in order for the motor to run. There are two main types of pedelecs: the PAS paradigm used in Japan, and the EPAC paradigm used in Europe.

Permanent Magnet – A permanent magnet is a magnet that stays magnetized without the need for an external power source. These are the most common type of motors used in light electric vehicles (LEVs).

RIDE e MTB Tip: Are you thinking about building an eBike? It isn’t very hard – Heck I’ve got step by step instructions with videos along with all the tools. Check it out 👉 How to Build a Mid-Drive Electric Bike

Push to start, or pedal to start – Some ebikes require the rider to pedal a few strokes or reach a certain speed before the motor can be activated, a feature known as push to start or pedal to start.

Range – The range of an ebike is the distance it can travel on a single charge, which is affected by factors such as the size of the battery, power efficiency, weight, terrain, incline, and wind conditions. Read about bike range in this guide 👉 Guide to Electric Mountain Bike Range

Regenerative braking – Regenerative braking is a feature that improves the energy efficiency of an ebike by storing kinetic energy that would otherwise be lost during braking and using it to charge the battery.

S-Pedelec – An S-Pedelec is a bicycle with electric pedal assistance that can reach speeds of up to 45 km/h and has a motor with a permanent output of up to 500 W. It requires registration, insurance, and a moped, motorcycle, or car driver’s license.

Sag – Sag, or negative travel, refers to the amount that a fork or rear shock compresses under the rider’s body weight when they are sitting still on the bike. Sag allows the suspension to adapt to the irregularities of the trail for improved traction and bike control, and is usually between 20% and 30% of the total travel.

Speed Controller – A speed controller is a device that regulates the speed of an electric motor. Also referred to as the motor controller or simply controller. This is the computer that controls the current from the battery to the motor.

eBike Speed Sensor
eBike Speed Sensor

Speed Sensor – A speed sensor is a device that detects the rate of pedaling and is used to activate the power in pedelecs. It is not as smooth as a torque sensor system. Read more about speed sensors 👉 What is an eBike Speed Sensor and How Does It Work

SOC – or state of charge, is a measure of how much usable energy is left in the battery, similar to a gas gauge. It can be complex to accurately determine and is important for user satisfaction.

SVRLA – or sealed valve regulated lead acid, batteries are the most common type of ebike and e-scooter battery.

Tire Scrubber or Friction Drive – tire scrubber, also known as a friction drive, is a friction roller that rides against the tire of a vehicle and uses the outer diameter of the tire as a gear reduction and point of power application. It is a simple system that was once the primary power application for electric bikes.

EBike Thumb Throttle
EBike Thumb Throttle

Throttle – A throttle is a device that the rider uses to control the speed of the vehicle, which can be activated using a twist grip, thumb, or other method. I’ve got all the details needed in my article 👉 What is an eBike Throttle and How Does it Work

Travel – Travel refers to the amount that a fork or rear suspension can compress and extend. The longer the travel, the better the suspension can compensate for the irregularities of the trail. For a comfortable ride on an eMTB we recommend travel of 120 mm.

Torque – Torque is measured in Newton meters (Nm) and describes the rotational power of the motor that is used to assist the rider while pedaling. The higher the torque, the stronger the support the rider gets.

Torque Arms for eBike – torque arms are small brackets mounted to the drop-outs of electric bikes. Hub motors apply force against the bike frame (drop-out) this force is significant and can deform the drop-outs causing bike frame failure. The torque arm uses leverage to spread the torque over a larger area of the frame.

Torque Sensor for eBike – A torque sensor is a device used on electric bikes (ebikes) that measures the energy applied through pedaling. This information is used in pedal assist systems (PAS) and is useful for all types of pedelec bikes. Read more about torque sensing eBikes in this article. 👉 What is Torque Sensing on an eBike and How does it Work

User Interface for eBike – The user interface of an ebike is the means by which the rider interacts with the machine, including controls, seat, pedals, and display of information such as speed, distance, and battery state of charge (SOC). These interfaces are increasingly becoming interactive with the internet and GPS through the use of phones and other devices.

Vehicle Controller – The vehicle controller is an electronic circuit that monitors and regulates the motor controller, user interface, battery management system, and other features of the ebike.

Volts, Voltage – refers to the force that a given level of electrical flow can exert. It is a measure of electrical potential difference.

Walk assist –Walk assist is a feature that helps riders move their ebike around when they are unable to ride, or helps them start riding. The motor accelerates the ebike to a speed of approximately 6 km/h, making it easier to walk with the bike or to start pedaling. This is especially useful when setting off on an incline.

Watts – Watts is a unit of measurement for the amount of work done. It can be used for various applications, including electrical, muscle, and internal combustion engine (ICE) systems. In the context of electric bikes (ebikes), watts refer to the amount of work being done or that can be done by the system or device. For example, a 500-watt motor is capable of twice the work of a 250-watt motor, assuming all other factors are equal. A fit human can produce about 75 watts of work over an extended period, while athletes may be able to produce more wattage for short periods of time. One horsepower is approximately 750 watts.

Watt Hour – A watt hour is a unit of energy commonly used to describe battery capacity for electric bikes and other light electric vehicles (LEVs). It is calculated by multiplying the volts and amp-hours (AH) of the battery. For example, a pedelec bike may have a 36-volt, 10 AH battery with a capacity of 360 watt hours.

Wire Diagram for Ebike – A wire diagram for an ebike is a visual representation of the electrical connections and wiring of the bike.

Wiring Harness or Harness – A wiring harness, or harness, is the set of wires, connectors, and switches that carry electrical current and signals throughout the ebike.

Find more information and articles in the How To Section of this website 👉 Everything About eBike How To

David Humphries Author at Ride e MTB

Hi David Humphries here the guy doing all the pedaling behind the scenes with this blog. I’ve been in the MTB world for a while and recently started getting into eMTBs. You can check out more about me HERE and on my other passion project – DIYMountainBike.com