Battery
The vehicle's energy source. Which battery types exist, and what are their pros and cons?
Read more →The Drivetrain in Two-Wheeled Electric Vehicles
Battery, motor, controller, and throttle. The drivetrain is the power chain that turns stored energy into motion. Here you get an overview with deeper guides on dedicated pages.
Imagine a DIY electric two-wheeler that can challenge many electric mopeds in acceleration. The secret is the drivetrain: battery, motor controller, motor, and throttle working together to turn energy into propulsion. We explain the key components, how they interact, and why Gbike chose these solutions for our kits.
Each Component
Want to dive deeper into each component? Continue to a dedicated deep dive for every part.
Motor Controller
The drivetrain's brain. What does a controller do, and how does it work?
Read more →Motor
What motor types are there, and what are their strengths and tradeoffs?
Read more →Throttle
How does the throttle work, and what throttle control types are used?
Read more →Component-by-Component Overview
The drivetrain consists of four main components that work together in a clear chain. Here we break them down one by one and explain what each part does.
1. Battery - the energy source
The battery is the drivetrain's power source and stores all electrical energy that the motor converts into motion. In modern electric vehicles, lithium-ion batteries are used almost exclusively thanks to their high energy density and relatively low weight.
Important: Battery health affects the performance of the whole system. A well-maintained battery with correct charging and storage can last for thousands of charge cycles.
2. Motor controller - the brain
If the battery is the power source, the motor controller is the brain that decides how that power is used. The controller receives throttle signals and converts the battery's direct current (DC) into the alternating current (AC) the motor needs.
3. Motor - the power converter
The motor is the component that actually converts electrical energy into mechanical rotation. In GBIKE 1 we use a Permanent magnet synchronous motor (PMSM) in a direct-drive hub-motor configuration where the motor sits directly in the rear wheel without chain or gearbox.
There are several types of PMSM, and we cover them in detail in our article on motors.
4. Throttle - rider control
The throttle is the only component in the drivetrain you physically interact with as a rider. It is your direct control over how much power the motor should deliver.
Most modern throttles use a Hall sensor that converts throttle position into an electrical signal. At idle (no throttle), the sensor reads around 1 V. At full throttle, the signal rises to around 4 V. The controller reads this voltage and adjusts motor output accordingly.
The Complete System - How Components Work Together
We have broken the drivetrain into parts, but the full system is what creates the real experience. Example: you apply half throttle, the Hall sensor sends roughly 2-3 V to the controller, phase currents are metered, the battery delivers around 40 A within safe limits, the motor builds torque, and speed rises smoothly. At full throttle, phase voltage climbs toward the battery's 72 V as rpm increases, while staying within current limits around 80 A.
Component matching is critical. Battery voltage and current, controller limits, and motor durability must be balanced. In GBIKE 1, the parts are dimensioned for each other with a 72 V battery pack, current limits around 80 A, and a 35 mm stator built for demanding use, resulting in a strong and reliable drivetrain.
In development: GBIKE 2, our next-generation kit where we apply these lessons and raise the bar.