E-Bikes Explained

What an e-bike is (and isn’t)

An e-bike is a bicycle with an electric motor and a battery that help you along. You still steer, brake and, on most e-bikes, pedal. The motor makes hills flatter, headwinds gentler and long rides shorter.

In Alberta, an e-bike that meets the province’s rules is a power bicycle. Among other things, its motor is rated at 500 W or less and it stops assisting at 32 km/h on level ground. Above those limits, it isn’t a power bicycle any more. The full list is on Rules and safety.

An e-bike is not automatically the right choice. It costs more to buy, weighs more, has more parts that can fail, and needs battery care. For short, flat rides, a light pedal bike can be simpler and more fun. But for longer rides, coulee hills, a daily commute or our wind, an e-bike can be the difference between riding and not riding. Many riders also find it lets them ride with faster friends or family.

Motors: front hub, rear hub, mid-drive

There are three common places to put the motor. Each changes how the bike feels.

Torque and power, simply

Power, in watts, is how much work the motor can do each second. Torque, in newton-metres, is how hard it can twist. On a steep coulee climb from a standstill, torque is what you feel. Two motors with the same 500 W rating can feel very different on a hill, because torque and the way the system manages power differ. A test ride up a real hill tells you more than the numbers.

Cadence and torque sensors

A pedal-assist e-bike needs a way to know you’re pedalling. There are two common kinds of sensor, and they’re a big reason one e-bike feels natural and another feels odd.

Neither is wrong. Some riders, especially those with sore knees, like that a cadence sensor gives plenty of help with little pressure. Others find a torque sensor more natural and easier to control on crowded pathways. Ride one of each.

Throttles

Some e-bikes also have a throttle, which drives the bike without pedalling. A throttle can help you get moving from a stop on a hill, or keep going if your legs give out. Alberta’s power bicycle rules allow throttles on bikes that meet the other criteria, but some trails and parks allow only pedal assist.

Batteries: volts, amp-hours and watt-hours

This is where most confusion starts. Here’s the short version.

Watt-hours = volts × amp-hours.

• A 36 V, 14 Ah battery holds 36 × 14 = 504 Wh.
• A 48 V, 14 Ah battery holds 48 × 14 = 672 Wh.
• A 48 V, 10 Ah battery holds 48 × 10 = 480 Wh, a little less than the first one, despite the higher voltage.

So compare batteries by watt-hours, not by volts or amp-hours alone. If a seller lists only volts and amp-hours, multiply them.

Removable or integrated?

• Removable batteries can be taken indoors to charge and to store over winter, and taken off before putting the bike on a hitch rack. Very useful in Lethbridge, where garages get cold.
• Integrated batteries are built into the frame. They look tidy and are protected, but some can only be removed with tools, or not easily at all. Then the whole bike has to come inside to charge in the cold.

Charging

• Use only the charger that came with the bike, or the maker’s approved replacement.
• Charge indoors, at room temperature, on a hard surface, away from anything that can burn, and away from exit doors.
• Let a battery cool after a ride before charging, and let a cold battery warm to room temperature first.
• Don’t leave it charging unattended or overnight while you sleep. Unplug when it’s full.
• Charging time depends on battery size and charger. Several hours for a full charge is common. Check your manual.

Replacement batteries and the future

Batteries wear out. They lose capacity a little every year and with every charge. At some point you’ll want a new one, and a replacement can be one of the biggest single costs of owning an e-bike. Before you buy, ask:

• Is the battery a standard shape used by many bikes, or unique to this model?
• Will replacements likely still be available in five or more years?
• Is there a battery warranty, and what does it cover?

Health Canada advises replacing batteries with original parts from the manufacturer or the dealer, and never modifying a battery or adding extra batteries to increase voltage or capacity.

Real-world range and a reserve

An advertised range is a best case, not a promise. It’s usually measured on flat ground, in mild weather, with a light rider, low assist and no wind. A Lethbridge ride home into a 40 km/h west wind on a cool October afternoon is none of those things.

What uses up range

A worked example

The best way to estimate range is to measure your own riding. Ride your usual routes for a couple of weeks and note the kilometres and how many bars or percent of battery you used. Until then, this example shows the method. The consumption numbers below are illustrations, not measurements; every bike and rider is different.

1. Find the battery’s energy. Say it’s 48 V and 14 Ah. 48 × 14 = 672 Wh.
2. Allow for what you can actually use. Most systems cut the motor before the battery is completely empty, and an older battery holds less. Suppose you can count on about 90 percent: 672 × 0.9 ≈ 600 Wh.
3. Estimate energy per kilometre for an easy day. Suppose that on a calm summer day, at a moderate assist level, on pathways, your bike uses about 12 Wh per km. 600 ÷ 12 = 50 km.
4. Estimate a hard day. Now suppose it’s 2°C, windy, and you climb out of the coulees twice. Your consumption might double to around 24 Wh per km, and the cold might reduce what the battery delivers to around 500 Wh. 500 ÷ 24 ≈ 21 km.
5. Keep a reserve. Plan never to use the last 20 to 25 percent. On the hard day, that leaves about 16 km you can count on. For an out-and-back ride, that’s about 8 km out, and 8 km home into whatever the wind is doing.

Same bike, same battery: about 50 km on an easy day, about 16 km you can rely on for a hard one. That’s why advertised range is a poor guide.

Cold, heat and battery age

• Cold rides. Lithium-ion batteries give less energy when cold, so range drops on cold days. Start with a battery that’s been stored indoors at room temperature, and keep it on the bike only for the ride. Some riders use an insulated battery cover in the shoulder seasons.
• Never charge a cold battery. Let it warm to room temperature first. Safety organizations warn against charging in extreme cold or heat.
• Heat. Don’t leave the bike or battery in direct summer sun, a closed car or a hot truck bed for hours.
• Winter storage. Store the battery indoors, above freezing and away from heat sources, at the partial charge your manual recommends. Most manuals say not to store a battery either completely full or completely empty for months. See winter storage.
• Battery age. Capacity declines gradually with age and use. A battery that gave 40 km in its first summer won’t give quite that after several years. Plan your reserve around the battery you have, not the one you bought.

Brakes, gears and drivetrain

An e-bike is heavier and often faster than a pedal bike, so the parts that slow it down and transmit power work harder.

Brakes

• Hydraulic disc brakes use fluid in a sealed line. They’re strong, need a light touch, and adjust themselves as pads wear. They’re the better choice for heavy e-bikes and steep coulee descents. Bleeding the system is a shop job.
• Mechanical disc brakes use a cable. Simpler and easier to fix at home, but need more hand force and regular adjustment as pads wear.
• Rotor size. Disc rotors commonly come in sizes such as 160, 180 and 203 mm. A larger rotor gives more stopping power and handles heat better on long descents. Heavy e-bikes and cargo bikes benefit from larger rotors, especially at the front.
• Motor cut-off. Alberta’s power bicycle criteria require that, on a bike with an accelerator, assistance stops as soon as the brakes are applied. Many e-bikes cut the motor through sensors in the brake levers.

Gears

• Gear range. A wide range, with a very low gear, matters for climbing coulees, especially if the battery runs low.
• Derailleurs move the chain across a stack of cogs. Light and efficient with a wide range, but exposed to damage and need adjustment.
• Internal gear hubs keep the gears sealed inside the rear hub. Low maintenance, you can shift while stopped, and they shrug off grit and winter grime. Heavier, and usually a narrower range.

Chain or belt

• Chains are cheap, efficient and work with any gear system. They need regular cleaning and oiling, and wear out, faster with mid-drive motors.
• Belt drives are clean, quiet and long-lasting, with no oil. They need a special frame and usually an internal gear hub or a single speed, and a replacement belt can be harder to find.

Tires, suspension and consumables

• Tires. E-bike-rated tires are built for the extra weight and speed. Puncture-resistant tires are worth considering for pathways and gravel, where thorns, glass and sharp stones turn up. Fixing a flat on a heavy e-bike, especially a rear hub motor, is harder than on a pedal bike.
• Suspension. A suspension fork or seat post can soften cracks and bumps. But suspension adds weight and service, and for paved pathways, wider tires at sensible pressure often do the job.
• Consumables. Brake pads, chains, cogs and tires wear faster on e-bikes because of the weight and power. Budget for them every year. See ownership costs.

Riding with no assist

Sooner or later, the battery runs flat or you switch the motor off. What happens next depends on the bike.

• It’s heavier than a pedal bike. You’re moving the weight of the motor and battery with your own legs. On the flat it’s manageable. On a coulee climb, a heavy e-bike with no assist can be very hard work, and some riders end up walking it.
• Some motors add drag. Mid-drive motors and most geared hub motors freewheel fairly easily when off. Direct-drive (gearless) hub motors can add noticeable drag. Ask, and try riding the bike with the assist switched off on the test ride.
• Gears matter more. A low gear makes a flat-battery ride home possible.
• Lights may go out. If your lights run from the main battery, a flat battery can leave you without lights. Some systems keep a little reserve for the lights; check yours, or carry a small backup light.
• Heavy bikes are hard to push. Some e-bikes have a “walk assist” mode that helps you push the bike up a slope on foot, but it needs battery.

Battery fire safety and certification

Lithium-ion batteries store a lot of energy in a small space. Most give years of trouble-free service. But damaged, poorly made or modified batteries, and incompatible chargers, can overheat and catch fire, and those fires are hard to put out. A little care goes a long way.

Choose certified equipment

• ANSI/CAN/UL 2849 is the joint Canada-US safety standard for the electrical system of an e-bike: battery, charger and motor system tested together. Health Canada and Transport Canada recommend that e-bikes and their batteries comply with it.
• UL 2271 is the safety standard for batteries used in light electric vehicles, including e-bikes. A battery certified to UL 2271 has been tested on its own; UL 2849 tests the whole system.
• Look for a certification mark from an accredited certification body on the bike, battery and charger. Health Canada advises using a charger with a Canadian certification mark, such as those from CSA, UL, Intertek and other accredited bodies.
• Ask the seller which standard the bike was certified to, and by whom. A vague “it meets all standards” isn’t an answer.

Charge and store with care

1. Use the original charger or the manufacturer’s approved replacement. Never use a charger “that fits”.
2. Charge where you’ll notice trouble. Lethbridge Fire and Emergency Services suggests charging devices in a room with someone present, and not for longer than the manufacturer recommends.
3. Keep the exit clear. Don’t charge or park an e-bike in a hallway or by the door you’d use to escape a fire.
4. Fit a smoke alarm where you charge.
5. Keep it away from things that burn: beds, couches, cushions, paper, and fuel cans in the garage.
6. Let it cool after a ride before charging, and let a cold battery warm up first.

Warning signs

Stop using a battery that has been dropped hard, punctured or crushed, or that is swollen, cracked, leaking, unusually hot, smells strange or makes popping or hissing sounds. Don’t charge it. If it’s smoking or on fire, get everyone out and call 911.

Helmets for e-bikes: why it matters

An e-bike makes it easy to ride faster than you would on a pedal bike, and to keep that speed up hills and into the wind. In Alberta, a power bicycle can assist you up to 32 km/h on level ground, and you can go faster than that on your own pedalling or downhill. The bike is also heavier. All of that means more energy in a crash.

The energy of a moving rider rises with the square of the speed. At 32 km/h you carry about two and a half times the energy you’d have at 20 km/h (32 × 32 ÷ 20 × 20 ≈ 2.6). A helmet can’t remove that energy, but it can spread out and slow down the blow to your head.

Speed shows up in hospital data too. A study at a Dutch trauma centre of 834 injured cyclists, 379 of them on e-bikes, found that riders who crashed at 26 to 45 km/h were several times more likely to have a brain injury than riders going slower. Speed, alcohol and blood-thinning medicines mattered most; the type of bike, on its own, did not. On an e-bike, you spend more of your time at those higher speeds.

Parachute, Canada’s national injury prevention charity, reports that bicycle helmets reduce head injuries by more than 40 per cent, serious head injuries by 60 per cent, and traumatic brain injury by more than 50 per cent.

Three kinds of helmet

In a lab test, a helmet on a dummy head is dropped onto a steel block. The test speed is how fast the helmet hits the block, not how fast the bike was going. Most of a real head strike comes from falling to the ground, and riding speed adds to it, often at an angle. A helmet built and tested for a harder hit leaves more margin.

An e-bike-rated helmet isn’t magic. Its lab test is only a little harder than the North American bicycle test. Its biggest gains are more coverage at the temples and the back of the head, which the Dutch road safety institute SWOV highlights, and a test built around faster riding. Whatever you choose, a helmet that fits and is worn every ride does far more than a better one left at home.

Rotation. Many crashes twist the head as well as hit it. Some helmets add a low-friction layer or similar system meant to reduce that twist. In a 2024 lab study at Imperial College London, these systems reduced rotation in the helmets tested, but not every helmet that had one was among the best performers. The main bicycle standards don’t yet test for rotation, so treat it as a bonus, not a substitute for fit and coverage.

Fit and replacement checklist

1. Check the label. Look for a certification label inside the helmet. For an e-bike, look for NTA 8776 or a motorcycle standard, and read the In Alberta box above.
2. Try it on. It should sit level and feel snug. Use the fit dial or pads that come with it to adjust the fit.
3. 2: the front edge sits about two fingers’ width above your eyebrows, level, covering your forehead.
4. V: the side straps form a V just under each ear.
5. 1: buckle the chin strap. You should fit only one finger between the strap and your chin.
6. Shake test. Shake your head side to side and nod. The helmet shouldn’t move.
7. Replace it after any crash where you hit your head, even if it looks fine. The foam is crushed once and can’t protect you the same way again.
8. Replace it after about five years, as Parachute recommends for bike helmets, or sooner if the maker says so, or if it’s cracked, faded or the straps are worn.
9. Follow the maker’s care instructions for cleaning and storage.

Sources

• Government of Alberta, Cycling safety equipment (helmet rules, approved bicycle helmet standards, power bicycle helmet choice), published May 8, 2024: alberta.ca/safety-equipment
• Government of Alberta, Rules and Regulations Applying to Small Vehicles (updated November 2018), power bicycle criteria, helmet rule and the November 20, 2018 Registrar’s exemption: transportation.alberta.ca (PDF)
• Alberta Vehicle Equipment Regulation, AR 122/2009 (s. 107 to 112, helmets): kings-printer.alberta.ca (PDF)
• Government of Alberta, Vehicle and helmet exemptions (Sikh turban exemption): alberta.ca
• City of Calgary, Cycling bylaws and safety tips (provincial helmet rule for power-assist bicycles, all ages): calgary.ca
• City of Lethbridge, “Council approves updated Bicycle Bylaw” (November 12, 2024): lethbridge.ca; Trails and Pathways: lethbridge.ca
• Bicycle Helmet Safety Institute (non-profit), Comparison of helmet standards (2025), impact test speeds for CPSC, EN 1078 and NTA 8776: helmets.org (PDF)
• SWOV (Dutch Institute for Road Safety Research), Is helmet use mandatory for (speed) pedelecs? and Why are helmets mandatory on speed pedelecs?: swov.nl, swov.nl
• CONEBI (Confederation of the European Bicycle Industry), New Dutch standard for speed-EPAC helmet published (August 2016): conebi.eu
• Verbeek AJM and others, E-bike and classic bicycle-related traumatic brain injuries presenting to the emergency department, Emergency Medicine Journal 2021;38:279–284: doi.org/10.1136/emermed-2019-208811
• Baker CE and others, How well do popular bicycle helmets protect from different types of head injury?, Annals of Biomedical Engineering 2024;52:3326–3364: eprints.whiterose.ac.uk (PDF)
• Parachute, Helmets for bicycles, inline skating, scooter riding and skateboarding (effectiveness, 2V1 fit, replacement), reviewed March 9, 2026: parachute.ca
• LiveWire Calgary, “Rule changes are being explored as e-scooter, power bike use jumps” (July 7, 2026): livewirecalgary.com

Tool B: Which features do I need?

Motor type, sensor, battery size, tires, suspension, brakes, frame, gears, seat and controls: this tool asks about your riding and suggests which features are worth paying for and which you can skip.

Sources

• Health Canada and Transport Canada, Misuse or modification of lithium-ion batteries in e-mobility devices can be extremely dangerous (May 2023), including the recommendation for ANSI/CAN/UL 2849: recalls-rappels.canada.ca
• Health Canada, Factsheet: Larger lithium-ion battery systems (2025), certification marks and charging location: canada.ca
• UL Solutions, E-Bike/Micromobility Device Safety: Product Certification (titles and scope of UL 2849 and UL 2271): ul.com
• UL Standards & Engagement (non-profit), 5 Electric Bike and Scooter Safety Tips: ulse.org
• London Fire Brigade, Charging electric bike and electric scooter lithium batteries: london-fire.gov.uk
• My Lethbridge Now, “Lithium battery fires prompt warning from Lethbridge emergency officials” (June 16, 2022), advice from Lethbridge Fire and Emergency Services: mylethbridgenow.com
• Government of Alberta, Rules and Regulations Applying to Small Vehicles (updated November 2018), power bicycle criteria: transportation.alberta.ca (PDF)
• David Gordon Wilson, Bicycling Science (MIT Press), on air resistance and rolling resistance.