Introduce your young rider to the excitement of off-road riding with the RFN Warrior SX-E400 Kids Electric Dirt Bike – a compact electric motocross-style bike designed specifically for younger riders taking their first steps into powered two-wheel riding.

Powered by a 36V 250W electric motor producing up to 400W peak power and 26Nm of peak rear-wheel torque, the SX-E400 combines manageable performance with genuine dirt-bike styling and a proper footpeg riding position.

With three selectable speed modes from 5mph to 15.5mph, a 36V 5.2Ah lithium battery, front and rear suspension, 12-inch wheels and a rear disc brake, the SX-E400 gives young riders a bike they can develop their confidence and skills on rather than immediately outgrow.

RFN recommends the SX-E400 for riders approximately 3–6 years old or 90–110cm tall, making it the smallest and most accessible model in the RFN Warrior Kids range.

⚡ 250W Motor with 400W Peak Power

At the heart of the RFN Warrior SX-E400 is a 36V 250W electric motor, delivering up to 400W peak power.

More importantly, the SX-E400 produces up to 26Nm of peak torque at the rear wheel, providing responsive acceleration while retaining manageable performance for younger riders.

The simple electronic twist throttle and direct-drive chain system mean there's no clutch or conventional gearbox to master.

Young riders can concentrate on developing the skills that matter:

• Throttle control
• Balance and coordination
• Braking
• Cornering
• Body positioning
• Confidence on two wheels
• Basic off-road riding technique

For children with an interest in motocross or dirt bikes, the SX-E400 provides an exciting introduction to a proper footpeg-style electric bike.

🏁 3 Selectable Speed Modes

One of the SX-E400's most important features is its three selectable speed settings.

Rather than giving a young rider immediate access to the bike's maximum performance, parents can start them at a much more manageable speed and increase the performance as their confidence and ability develop.

ECO Mode – 5mph

The lowest setting is ideal for introducing a young rider to the bike and allowing them to become comfortable with the throttle, brakes and riding position.

STD Mode – 7.5mph

Once their control and confidence improve, Standard Mode provides a useful step up in performance.

SPORT Mode – 15.5mph

Sport Mode unlocks the SX-E400's maximum speed of approximately 15.5mph for confident and experienced riders.

This 5mph → 7.5mph → 15.5mph progression is one of the reasons the SX-E400 makes such a strong first electric dirt bike.

Maximum speed can vary depending on rider weight, terrain, battery condition and riding conditions.

🔋 36V 5.2Ah Lithium Battery

The SX-E400 is powered by a 36V 5.2Ah lithium battery, providing plenty of capacity for young riders to practise and have fun.

RFN quotes a maximum range of up to approximately 11 miles in ECO mode, or around 2 hours of riding, with a full 0–100% recharge taking approximately 2.5 hours.

Battery & Performance

• Battery: 36V 5.2Ah Lithium
• Motor: 36V 250W
• Peak Power: 400W
• Peak Rear-Wheel Torque: 26Nm
• Maximum Speed: 15.5mph
• Maximum Range: Up to 11 miles in ECO Mode
• ECO Runtime: Approx. 2 hours
• Charge Time: Approx. 2.5 hours

Actual range and runtime will depend on rider weight, terrain, speed mode, riding style and conditions.

🏍️ A Proper Kids Electric Dirt Bike

The RFN Warrior SX-E400 provides a very different riding experience from a traditional electric balance bike.

Its footrests, twist throttle, suspension and motocross-inspired riding position introduce children to many of the fundamentals they'll use if they progress onto larger electric dirt bikes or motocross machines.

It's an excellent platform for learning:

• Standing on the footpegs
• Correct body positioning
• Throttle control
• Braking technique
• Cornering
• Weight transfer
• Riding across uneven terrain

This makes the SX-E400 particularly appealing to motocross families looking for an early introduction to powered riding.

🔧 Front & Rear Suspension

The SX-E400 is designed to cope with suitable off-road terrain rather than simply smooth surfaces.

At the front, RFN spring suspension provides 85mm of stroke, helping absorb bumps and improve front-wheel control.

RFN spring suspension is also fitted at the rear, helping provide additional comfort and control across uneven ground.

🛑 140mm Rear Disc Brake

The RFN Warrior SX-E400 features an RFN 140mm rear disc brake, providing predictable stopping performance for developing riders.

A rear-only braking setup also keeps the controls straightforward for younger children learning to coordinate throttle, steering and braking.

🛞 12" Front & Rear Wheels

The SX-E400 uses compact 12-inch front and rear one-piece wheels, helping keep the overall dimensions manageable for smaller riders.

Combined with the bike's 460mm seat height and 665mm wheelbase, the compact wheel setup creates a riding position designed specifically around younger children rather than simply scaling down an adult dirt bike.

💪 High-Grade Carbon Steel Race Frame

RFN builds the SX-E400 around a high-grade carbon steel race frame, providing the strength and durability required for young off-road riders.

The complete bike weighs approximately 18kg and supports a maximum rider weight of 50kg.

🛡️ Built-In Safety Features

RFN has incorporated several useful features specifically for younger riders.

Lanyard Safety System

The lanyard system provides an additional method of cutting power to the bike, particularly useful when young riders are learning.

Power Button Cover

A protective cover over the power button helps prevent unintended operation.

Combined with the three selectable speed settings, these features allow parents to introduce the SX-E400's performance progressively.

💧 IPX5 Water Resistance

RFN rates the SX-E400 to IPX5, meaning it is protected against low-pressure water jets from different angles.

This does not mean the bike is waterproof or suitable for immersion in water. Appropriate care should always be taken around water and when cleaning the bike.

👦 Who Is the RFN Warrior SX-E400 For?

RFN recommends the SX-E400 for riders approximately:

3–6 years old

and approximately:

90–110cm tall

The bike has a 460mm seat height and a maximum rider weight of 50kg.

Age should always be treated as a guide. When choosing a kids electric dirt bike, parents should also consider the child's:

• Height
• Inside leg
• Weight
• Balance and coordination
• Previous riding experience
• Confidence
• Physical ability

If you're deciding between the RFN Warrior SX-E400, SX-E500 or SX-E700, Motocross4U can help you choose the correct model based on the rider rather than age alone.

RFN Warrior SX-E400 Technical Specifications

These specifications are taken from RFN's current SX-E400 technical information.

Why Choose the RFN Warrior SX-E400?

The RFN Warrior SX-E400 is designed to give younger children a genuine introduction to electric dirt-bike riding without immediately putting them on a large or excessively powerful machine.

Key Features

• ⚡ 36V 250W electric motor
• 🚀 400W peak power
• 💪 26Nm peak rear-wheel torque
• 🏁 3 selectable speed modes
• 💨 5 / 7.5 / 15.5mph settings
• 🔋 36V 5.2Ah lithium battery
• 🔋 Up to 11-mile ECO range
• ⏱️ Up to approx. 2-hour ECO runtime
• ⚡ Approx. 2.5-hour charge time
• 🔧 Front & rear suspension
• 🛑 140mm rear disc brake
• 🛞 12" front & rear wheels
• 💪 High-grade carbon steel race frame
• 🛡️ Lanyard safety system
• 💧 IPX5 water resistance
• 👦 RFN guide: ages 3–6 / 90–110cm

RFN SX-E400 vs SX-E500 – Which Should You Choose?

The SX-E400 is the entry point into RFN's Warrior Kids electric dirt-bike range and is designed around smaller, younger riders.

For a taller or more experienced child, the RFN Warrior SX-E500 steps up to 14-inch wheels, higher speeds and increased performance.

The important thing is not simply choosing the most powerful bike. The correct model should match the rider's height, weight, confidence and experience.

If you're unsure, contact Motocross4U before ordering and we'll help you choose between the SX-E400, SX-E500 and SX-E700.

Why Buy Your RFN Warrior SX-E400 From Motocross4U?

Motocross4U specialises in RFN electric dirt bikes, electric motocross bikes, parts and accessories, helping families choose the right machine and keep it running.

When you purchase your RFN Warrior from Motocross4U, you'll benefit from:

• ✅ RFN electric bike specialists
• ✅ Expert motocross advice
• ✅ UK & Ireland delivery
• ✅ RFN replacement parts & accessories
• ✅ Parts and aftersales support
• ✅ Help choosing the correct RFN model
• ✅ Experienced motocross team

Compact, adjustable and designed to build real riding skills – the RFN Warrior SX-E400 400W Kids Electric Dirt Bike is an excellent first step into electric motocross riding.

Important Information

The RFN Warrior SX-E400 is an off-road electric dirt bike intended for appropriate off-road areas or private land with the landowner's permission. It is not intended for public-road use.

Young riders should be supervised by a responsible adult and always wear appropriate protective equipment, including a correctly fitted helmet, boots and protective clothing.