SX-E400 vs SX-E500 Specifications

Both bikes use removable 36V lithium batteries and adjustable speed settings, but the SX-E500 gains extra performance, larger wheels and hydraulic brakes.

RFN SX-E400 Overview

The RFN Warrior SX-E400 is designed as a genuine first RFN electric dirt bike. It is the best option for younger riders who need a smaller, lighter and more manageable machine.

With lower power delivery, 12-inch wheels and a lightweight chassis, the SX-E400 helps riders build throttle control, braking confidence and basic off-road skills without being overwhelmed.

Shop SX-E400 Bikes Kids Range Explained

RFN SX-E500 Overview

The RFN Warrior SX-E500 takes the same Warrior Kids formula and improves it in several key areas.

It uses a stronger motor, larger 14-inch wheels and hydraulic disc brakes, giving riders more capability and better long-term progression potential. For many families, this makes the SX-E500 the smarter buy.

Shop SX-E500 Bikes SX-E500 vs SX-E700 MX

Biggest Difference: Brakes

While most riders focus on power, one of the most important upgrades from the SX-E400 to the SX-E500 is the braking system.

The SX-E400 uses mechanical disc brakes, while the SX-E500 upgrades to hydraulic disc brakes. This gives the SX-E500 better braking feel, stronger stopping performance and easier control as rider confidence increases.

Biggest Difference: Wheel Size

The SX-E400 uses 12-inch wheels, while the SX-E500 uses larger 14-inch wheels.

The smaller wheels on the SX-E400 suit younger and smaller riders. The larger 14-inch wheels on the SX-E500 give more stability, better rough-ground ability and more room for rider progression.

Which Bike Is Better For Beginners?

The SX-E400 is the better choice for smaller beginners.

It is lighter, smaller and easier to manage, making it ideal for young riders who are completely new to electric dirt bikes. If confidence is the priority, the SX-E400 is the safer starting point.

Which Bike Is Better For Progression?

The SX-E500 is the better choice for progression.

It offers more power, stronger brakes, larger wheels and a longer usable lifespan. If your child already rides a balance bike confidently or has previous off-road experience, the SX-E500 is usually the better long-term buy.

Value For Money

The SX-E400 is excellent value for smaller riders who need a first RFN Warrior Kids bike. However, the SX-E500 usually offers better long-term value because it gives riders more room to grow.

If your child is very young or nervous, choose the SX-E400. If they are already confident and you want the best all-round Warrior Kids model between these two, choose the SX-E500.

Our Recommendation

• Best For Smaller Beginners: SX-E400
• Best Value Long-Term: SX-E500
• Best For Progression: SX-E500
• Best Overall: SX-E500

Final Verdict

Both bikes are excellent options in the RFN Warrior Kids range, but they suit slightly different riders.

If you are buying for a younger child who is completely new to riding, the RFN Warrior SX-E400 is the safer and more manageable starting point.

If your child already has some riding experience, or you want a bike that will last longer before needing an upgrade, the RFN Warrior SX-E500 is the better choice. The extra power, hydraulic brakes and larger wheels make it the standout model between the two.