Decoding Electric Mountain Bike Terminology: A Glossary for Buyers

Decoding Electric Mountain Bike Terminology: A Glossary for Buyers

Key Takeaways:

Introduction

For first-time buyers, the terminology around electric mountain bikes can be overwhelming. Acronyms and specifications seem like another language compared to shopping for a regular bicycle. But having a grasp of the key terms and components makes selecting the right eMTB far less intimidating.

This eMTB glossary defines all the crucial words and phrases surrounding electric mountain bikes from motors to batteries to suspension design and more. With these terms demystified, you can make sense of spec sheets and buyer guides to find the ideal eMTB. Let’s decode the jargon!

Key Electric Bike Terminology

To start, here are definitions of fundamental eBike words you’ll encounter:

• Electric Bicycle (eBike) – Broadly, any bicycle augmented with an electric motor and battery for pedal assist. Includes eMTBs, commuters, urban, cargo, etc.
• Electric Mountain Bike (eMTB) – A mountain bike model with integrated electric pedal assist capabilities. The motor amplifies rider power.
• Pedal Assist – Refers to the electric motor providing supplemental power only when the rider is actively pedaling up to 20mph, then it cuts out. No throttle mode.
• Pedelec – Portmanteau of “pedal” and “electric”. Used interchangeably with “eBike” in Europe to denote pedal assist only.
• Mid-drive Motor – Motor mounted centrally at the bike’s crank drivetrain compared to a hub motor in the wheel. Improves handling by centering weight.
• Hub Motor – Type of eBike motor located inside one of the wheels. Most common are rear hub motors. Slightly less efficient than mid-drive.

Now you can confidently use the main terminology to talk electric bikes like an insider!

Motor Power and Output

Motors deliver the power that transforms an eMTB:

• Watts (W) – Measurement of power output. More motor watts mean increased acceleration and torque for climbing. 750W is common for eMTBs.
• Newton-meters (Nm) of Torque – Indicates rotational pedaling force produced by the motor. Higher Nm provides more muscle to push over obstacles or up steep grades.
• Cadence Sensing – Motor turns on proportionally to how fast rider is pedaling measured in RPMs. Less refined assist.
• Torque Sensing – Motor provides assist corresponding to pedaling force and rider power input. More seamless delivery.
• Speed Sensing – Motor activates based on bike speed. Can sometimes lag in engagement compared to torque sensing.

Look for torque sensing motors with high power and torque ratings to provide the most natural and powerful eMTB experience.

Battery Basics

Batteries store and deliver energy to drive eMTB motors:

• Voltage (V) – Electrical force or pressure provided by the battery pack rated in volts. Higher voltage allows more power delivery.
• Amp-hours (Ah) – Current over time that indicates battery capacity. More Ah extends range before recharging.
• Watt-hours (Wh) – Total energy storage calculated by volts x amp-hours. 500+ Wh gives decent eMTB range.
• Charge Cycles – Number times a battery can be recharged before degrading. 500-1000 cycles is standard eMTB lifespan.

When assessing batteries, focus on max Watt-hours for range. Amp-hours x volts = Watt-hours. Higher Wh is better.

Suspension Types

Suspension allows eMTB wheels to absorb impacts for improved handling and control:

• Dual Suspension – Separate front fork and rear frame suspension provides cushy ride. Also called full suspension.
• Front Suspension Fork – Forks with telescoping legs and springs allow front wheel to absorb bumps only. Common on hardtails.
• Rear Shock – Provides rear suspension via linkage compressing shock between frame and swing arm.
• Travel – The amount of suspension fork/frame movement measured in millimeters (mm). More travel increases capability on rough terrain.
• Lockout – Suspension setting that firms up for maximum pedaling efficiency when needed. Lockouts help eMTB motors conserve battery.

Look for eMTBs with suspension travel matched to your riding style – 100-120mm for cross country, 130-170mm for trail/enduro.

eMTB Frame and Parts

Beyond motors and batteries, componentry impacts performance:

• Hardtail – eMTB with front suspension fork only and rigid rear frame. More affordable and efficient option.
• Dropout – Metal tabs at the fork/frame ends where rear wheel axle attaches providing vertical wheel adjustment.
• Cockpit – Collection of eMTB handlebar, stem, controls, display and seat that forms riding interface.
• Display – Handlebar mounted screen showing motor assist mode, battery level, speed, and other ride data.
• Wireless – eMTBs that allow control of assist levels and display data wirelessly via handlebar remote or app.
• Dropper Post – Seat post that can be lowered remotely for descents to gain stability. Retracts to optimize saddle height for pedaling/climbing.

Understanding frame features helps select the eMTB optimized for your style – whether hardtail, full suspension, or something in between.

Riding Modes and Tuning

Digital displays with control pads allow you to customize the eMTB motor assist to conditions and preferences:

• Riding Modes – Preset assist levels (Eco, Trail, Boost etc) that dictate how much motor output is provided relative to rider input.
• Custom Tuning – Many eMTBs allow finer settings adjustments via apps like max power output, responsiveness, max speed cutoff and more.
• Walk Assist – Low-speed option around 2 MPH for helping push the eMTB short distances or up steep pitches where pedaling isn’t possible.

Don’t settle for fixed assist levels. Seek the ability to tune the power delivery to your riding via multiple modes and custom settings.

Geometry and Frame Size

Like regular mountain bikes, eMTBs come in sizes to match rider dimensions and terrain:

• Wheel Size – Standard options are 27.5” or 29” wheels. 27.5” allow for more compact geometry while 29” rolls faster over bumps.
• Headtube Angle – Angle the headtube intersects with horizontal measured in degrees. Slacker angles around 64-66° provide more stable descending.
• Reach – Horizontal distance from bottom bracket to headtube determining cockpit length. Longer reach provides high speed stability.
• Standover Height – Clearance space between top tube and ground. Allows easy mounting and dismounting.
• Stack Height – Vertical distance from bottom bracket to top of head tube indicating handlebar elevation.

Test ride sizes and geometries to find the eMTB fit and handling characteristics optimized for your local trails.

Frequently Asked Questions

What does “pedal assist” mean on electric mountain bikes?

Pedal assist describes the motor providing supplemental power only while the rider is actively pedaling. The motor cuts off at 20mph in the USA. Pedal-assist ebikes do not have a throttle and require human input.

How does torque sensing differ from cadence sensing?

A torque sensing motor varies power depending on how hard you are pedaling, creating very natural acceleration. Cadence sensing simply engages the motor more as your pedal RPMs increase, so the power delivery feels more artificial.

What battery specs should I look for in an eMTB?

Focus on the Watt-hours (Wh) rating which indicates battery energy capacity for range. 500Wh is a good starting point. The Wh is calculated by multiplying voltage by amp-hours (Ah). Higher Wh extends range.

What does suspension travel indicate on eMTBs?

Travel refers to the amount of fork and frame movement measured in millimeters (mm). More travel allows the wheels to better absorb impacts from rocks, roots, drops, etc. 100-120mm is ideal for cross country. 130mm+ suits aggressive trail/gravity riding.

Why are dropper posts popular on eMTBs?

Dropper posts allow you to lower saddle position for descents, then pop it back up for optimal pedaling height on flats and climbs. This dynamic saddle height improves eMTB handling, stability, and confidence.

Conclusion

With this glossary illuminating key terms, you can now confidently navigate discussions and specifications related to electric mountain bikes. Understanding motor classes, battery specs, suspension travel, geometry, and components allows for making informed purchase decisions.

Refer back any time you hit confusing jargon. Our goal is to decode eMTB terminology so you can find the ideal match for your riding needs. Then let the trail adventures on quality electric power begin!