If you want a stock e-moto to pull harder, the controller is usually where the power is. The battery stores the energy and the motor turns it into torque, but the controller decides how much current goes to the motor and how fast. An aftermarket controller can turn a fun trail bike into something much faster. Here's how it works and what you need to know before you buy.
What a controller does
The controller sits between the battery and motor. It reads your throttle and sends current to the motor. It sets:
- Phase current – how hard the motor pulls. More current means more torque.
- Battery current – how much the controller draws from the pack.
- Throttle response – how aggressive or smooth power comes in.
- Regen braking – how much the motor slows the bike when you let off.
- Ride modes and limits – speed caps, power levels and protection settings.
Stock controllers are tuned for reliability and to keep the motor, battery and wiring cool under any rider. That leaves a lot of performance on the table.
What an upgrade gets you
- Much more torque off the line and stronger mid-range pull.
- Fully adjustable throttle maps and multiple ride modes, often tuned from a phone app.
- Adjustable regen and better heat management.
- The headroom to run a bigger motor or higher-voltage battery later.
The controllers we carry
EBMX X-9000 V3
Up to 50 kW output, 1,000 A phase current (1,600 A burst), IP67-rated CNC case, with a water-cooling option. Sold as a controller only or as a kit with a bike-specific harness. Harness kits are listed for the Sur-Ron Light Bee and Ultra Bee, Talaria Sting MX3/MX4/MX5, XXX and XXX Pro, E-Ride Pro SS 2.0, SS 3.0 and SR, and Rerode R1. Add-ons include the thumb regen throttle and Bluetooth module.
Ventus Aetos Pro, Max and Ultra
Built on the VTB V9600 Gen.2 platform, capable of up to 76 kW, and tuned through a detailed phone app with custom ride profiles and adjustable regen. Install kits are listed for the Sur-Ron Light Bee and Ultra Bee, Talaria Sting MX3/MX4/MX5, E-Ride Pro SS 2.0/3.0/SR, Rerode R1 and 79Bike Falcon Pro. The Talaria XXX needs an aftermarket motor or a connector change.
Match it to your battery
A controller can only use the current your battery can deliver. The stock battery's BMS limits how much it will put out, and pushing it too hard can trigger cutouts or shorten battery life. Ask us what your stock pack can handle before you turn everything up. For a bigger build, see our battery upgrade guide.
Match it to your motor
More current means more heat in the motor. A stock motor can handle a moderate bump, but big power needs a motor built for it:
- EBMX XLB-60 CORE Motor Kit – for the Sur-Ron Light Bee, E-Ride Pro S/SS 2.0/SS 3.0/SR and Talaria XXX.
- EBMX XTA-60 – for the Talaria Sting MX3/MX4.
- EBMX XUB-80 – for the Sur-Ron Ultra Bee, 40 kW peak.
- Sotion motor for Talaria Sting (12 kW rated / 24 kW peak) and Sotion motor for Sur-Ron Light Bee (13 kW rated / 26 kW peak) – 72V plug-and-play upgrades.
EBMX motors are tuned to work with the X-9000. They run on other controllers but may need your own tuning.
Torque vs. top speed
Controller settings and gearing trade off against each other. For trail riding and climbing, prioritize low-end torque and a smooth throttle. For open roads and fast tracks, gear taller for top speed. Gearing is the easiest lever:
- Bigger rear sprocket (or smaller front) – harder acceleration, lower top speed.
- Smaller rear sprocket (or bigger front) – higher top speed, softer launch, more heat on climbs.
Browse sprockets and chains, and use a stronger chain on a high-power build.
Don't forget the rest of the bike
More power means you'll arrive at corners faster. Before or alongside a power upgrade, look at brakes and suspension. Stock parts on most e-motos weren't designed for double the power.
Before you buy
- Power mods can affect your warranty. Check your bike's terms.
- A modified bike may no longer meet local street or trail rules for its class.
- Install carefully: correct harness, good connections, and secure, protected wiring.
- Start with a mild tune and work up as you get used to the power.
Planning a power build? Email support@tbelectricmoto.com with your bike and goals. Our riders will help you match the controller, harness, motor and gearing. Browse controllers and motors.
