Part 1 — A Little History
Where Did Electric Bikes Come From?
Electric bikes are not new. The first patent for an electric bicycle was filed in the United States in 1895 — more than 125 years ago. Early inventors imagined a motor attached to a regular bicycle frame. The idea was simple: use electricity to help the rider go farther and work less.
For most of the 1900s, electric bikes stayed rare. Batteries were too heavy, too expensive, and did not last long enough to be practical. Most people forgot the idea existed.
Then, in the 1990s and 2000s, two things changed. Lithium-ion batteries became affordable. And cities started getting more crowded. People needed a faster, cheaper way to get around than a car — but something more powerful than a regular bike.
By the 2010s, electric bikes, scooters, and other small electric vehicles were everywhere. Today, millions of these vehicles are in use around the world. And someone has to keep them running.
Part 2 — The Big Picture: How It All Works
It's the Same as an Electric Car — Just Smaller
You may have heard of electric cars like a Tesla or a Nissan Leaf. Those cars use the same basic system as every e-bike and e-scooter you will work on. The parts are the same. The concepts are the same. Only the size is different.
Here is the core idea: electricity stored in a battery flows through a controller to a motor, which spins a wheel. That is it. Everything else is just details built around this idea.
The controller is like a dimmer switch on a light. It controls how much power flows from the battery to the motor at any given moment. When you twist the throttle or pedal harder, you are turning that dimmer switch up — more power flows, and the motor spins faster.
Why Does This Matter for You as a Technician?
A vehicle arrives and the motor will not run. The battery indicator shows full charge. Where do you start, and why?
Start by confirming the battery voltage with a meter, not with the indicator lights. Indicator lights are driven by simple circuits that are often wrong — a pack can show four bars and still be far below the voltage the controller needs, and a pack with a tripped protection circuit can show full while delivering nothing at all.
Once you know what the battery is really doing, follow the chain: battery, then the connection from battery to controller, then the controller, then the motor. Checking the motor first feels productive, but the motor is the least likely part to be at fault and the most expensive to replace.
When a vehicle stops working, your job is to find where in this chain something went wrong. Is the battery dead? Is the controller broken? Is the motor faulty? Is a wire disconnected somewhere between them? If you understand the flow of energy, you can find the problem step by step.
Part 3 — Voltage: The Power Level
What Is Voltage and Why Does It Matter?
Voltage is a measurement of electrical pressure. Think of it like water pressure in a hose. Higher voltage means more pressure — and usually more power available to the motor.
In micromobility, most vehicles run on one of these common voltages:
| Voltage | Typical Vehicle | What to Expect |
|---|---|---|
| 24V | Small kids' e-bikes, older products | Low power, short range |
| 36V | Basic e-bikes, entry kick scooters | Everyday commuting, moderate speed |
| 48V | Mid-range e-bikes, most scooters | Most common — good power and range |
| 52V | Performance e-bikes | More speed and hill-climbing ability |
| 60–72V | E-mopeds, electric motorcycles | High power, faster speeds. Over 60V DC is a higher shock risk: work on these only with an experienced technician |
A measurement of electrical pressure in a circuit. Higher voltage = more potential power. A battery’s voltage determines its maximum power output — higher voltage means more power available at any moment. Measured with a tool called a multimeter.
A measurement of power output. Voltage × Current (amps) = Watts. A 48V motor drawing 20 amps produces 960 watts of power.
A measurement of how much energy a battery can store. While voltage determines how much power is available, amp-hours determine how long that power can be sustained. A 48V, 15Ah battery can deliver more total energy than a 48V, 10Ah battery — it will last longer before needing a recharge.
Reading a Battery Label Without Being Fooled
The practical consequence is that a reading which looks unexpectedly high is usually normal, and a reading that looks about right can be a problem. A 48V pack sitting at 48.0V is not healthy and full; it is roughly half discharged. You will learn the exact expected voltages for each chemistry and pack size in Module 5, and you will use them constantly.
Two batteries on the shelf look identical — same case, same mounting rails, same connector. One is 36V, one is 48V. What could go wrong if you fitted the wrong one?
The outside of a pack tells you almost nothing about what is inside it. Case and mounting hardware are shared across models; the cell count inside is what sets the voltage.
Fit a 48V pack to a vehicle built around 36V and you push roughly 54V into a controller rated for about 42V at full charge. Sometimes it fails immediately. Sometimes it works for a week and then fails, which is worse, because now the failure looks unrelated to the work you did.
Check the label, check the vehicle's rating, and confirm with a meter before connecting anything. This is a common repair scenario, not a trick question.
Part 4 — Vehicle Types
The Vehicles You Will Work On
This program covers six main types of personal mobility vehicles. You will see all of these in a real shop. Each one has different strengths, different common problems, and different rules.
Looks like a regular bicycle with a motor and battery added. Most common type in the U.S. Has three class levels (see Part 5).
Stand-up scooter with a deck, handlebars, and small wheels. Folds flat. Very common for short trips. The folding mechanism is a frequent repair point.
Looks like a gas-powered moped or small motorcycle. Higher voltage (48V–72V). May require registration and a license in some states.
Full-size motorcycle frame with electric drivetrain. Highest power and voltage in this program. Road-legal in most states. Safety is critical.
Single large wheel with self-balancing electronics. Common in recreation and youth markets. Has unique control systems compared to other vehicles.
No motor or battery. Common in community programs and thrift shops. Mechanical-only repairs. An important part of the Shandoka Cycles mission.
Most e-bikes and scooters use a hub motor, built into the center of the front or rear wheel. Some e-bikes use a mid-drive motor, mounted between the pedals. Module 2 covers both.
Part 5 — E-bike Classes & Rules
E-Bike Class Levels
A customer says their bike used to reach 28 mph and now tops out at 20. Give two possible explanations.
The speed limit may have been changed in the controller settings — by the owner, by a previous technician, or by a firmware update that reset the vehicle to a more conservative default. Controller settings are accessible and changeable, which is a fact worth carrying with you; it comes back in Module 6 when you are diagnosing vehicles with unknown histories.
Alternatively the vehicle may simply be delivering less than it used to. An aging battery that sags under load, or a motor working against a dragging brake, will lower the speed the vehicle can actually hold.
Both are ordinary. Measure before you conclude: check the setting, then check the pack under load.
In the United States, electric bikes are divided into three classes. The class tells you how the motor is activated and how fast it can go. These rules determine where a bike can legally be ridden.
Knowing the class is important for you as a technician because it affects what modifications are legal — and what is not.
- Motor works ONLY when pedaling
- Motor cuts off at 20 mph
- No throttle
- Allowed on most bike paths
- Has a throttle (twist or thumb)
- Motor cuts off at 20 mph
- Can also have pedal assist
- Allowed on most bike paths
- Pedal assist only
- Motor cuts off at 28 mph
- No throttle (in most states)
- Usually has a speedometer (required in most states)
- May be restricted from some bike paths
Many states require a permanent label on an e-bike's frame showing its class, top assisted speed and motor wattage. Compare what the label says with what the bike has.
Sit-Down Scooter and Kick Scooter Types
E-mopeds and kick scooters are not classified under the e-bike class system. Instead, they fall under different state and local rules. In many places:
- A kick scooter under 15 mph may be treated like a bicycle
- An e-moped over 30 mph likely requires a driver's license and registration
- Rules vary by city and state — always check local regulations when advising a customer
Part 6 — Safety Expectations
Operational Limits and Safety
Limits only matter if someone says them out loud, and that someone is usually you.
The conversation is easier than it sounds, because it is not an accusation. It is information, delivered plainly: here is what the vehicle is rated for, here is what I am seeing as a result, and here is what I would do about it. Most customers respond well to being told the truth by someone who clearly knows their trade. The ones who do not still deserve to hear it, and your notes on the ticket protect both of you.
Every vehicle in this program has design limits. These are the conditions it was built to handle safely. As a technician, you need to understand what those limits are — and recognize when a vehicle has been pushed past them.
Sometimes, a customer doesn’t know they are causing damage by the way they ride or store or use their electric mobility devices. Other times, they don’t care that the damage is being done because they want to ride that way and accept the risks.
But you do need to remind your customers of the damage you’ve noticed each time you see it.
Most kick scooters are rated for 220–265 lbs. E-bikes vary widely. Overloading causes frame stress, brake wear, and motor overheating.
Most vehicles have an IP (Ingress Protection) rating that tells you how much water exposure is safe. The second digit is water: IPX4 means splashes from any direction, IPX5 means water jets, and IPX7 means brief submersion. Riding in rain is different from submerging in a puddle.
Lithium batteries do not like extreme cold or heat. Charging a very cold battery can permanently damage it. Charge only between about 32°F and 104°F (0–40°C), and let a cold or hot pack reach room temperature first. You will learn safe charging practices in Module 5.
A poorly done repair can be more dangerous than no repair at all. You are responsible for the safety of every person who rides a vehicle you worked on.
Module 1 — Vocabulary Summary
Studying for This Module
You do not need to have memorized every definition to pass. You need to be able to explain each idea in your own words, the way you would to a customer standing at the counter — that is the level of understanding this trade actually runs on.
The five that matter most in your first week: what a battery, controller and motor each do, what voltage tells you about a vehicle, and the difference between the three e-bike classes. If those five are solid, the rest will settle as you meet them on real vehicles.
If a term still feels slippery, go back and read just that section again. Rereading one paragraph until it clicks is not falling behind — it is exactly how people who are good at this got that way.
Module 1 — Vocabulary
| Term | Definition |
|---|---|
| Battery | The energy storage unit in an electric vehicle; provides DC power to the controller. |
| Controller | The electronic brain of an EV drivetrain; converts battery power into motor commands and regulates speed. |
| Motor | Converts electrical energy from the controller into mechanical rotation to drive the wheel. |
| Voltage (V) | A measure of electrical potential or pressure; common micromobility voltages are 36V, 48V, and 52V. |
| Watt (W) | A unit of power equal to voltage multiplied by current; describes how much energy a system uses per second. |
| Amp-Hour (Ah) | A unit of battery capacity; indicates how much current a battery can deliver over one hour. |
| E-Bike Class | A regulatory category (Class 1, 2, or 3) defining max speed and whether a throttle is permitted. |
| Pedal Assist (PAS) | A motor-activation system that detects pedaling and provides proportional power assistance. |
| Throttle | A hand control that activates the motor directly, without requiring the rider to pedal. |
| Supply Chain Variation | The common condition where two vehicles of the same brand and model contain different internal components due to manufacturer sourcing changes. |
Before You Take the Knowledge Test
Answer these questions without referring to the reading. Review any section where you are unsure.
1. Name the four main components in the energy flow of an electric vehicle, in order.
2. Name four vehicle types covered in this program and describe one functional difference between any two of them.
3. Explain what voltage means in simple terms and name three common voltages used in micromobility systems.
4. What is the difference between a Class 1, Class 2, and Class 3 e-bike?
5. Why might two vehicles of the same brand and model have different internal components?
6. In your own words, explain why technician safety standards matter in a PEV repair setting.