Bonnell 775 MX: Top Speed, Real-World Performance & Better Alternatives

The Bonnell 775 MX has become a popular starting point for MX-style electric builds — but owners quickly start asking the same questions: how fast does it really go, what's worth upgrading, and is there something better? Here's a practical rundown.

Bonnell 775 MX top speed

Real-world top speed on a 775-class MX setup depends heavily on battery voltage, controller current and gearing. Out of the box these builds are quick, but they're single-speed by nature — which means you're always trading between low-end climbing grunt and high-end top speed. You can't have both at once without changing the drivetrain.

The single-speed limitation

A single fixed ratio is the biggest ceiling on this style of bike. Gear it for torque and you give up top speed; gear it for speed and hills become a struggle while the motor runs hotter. That compromise is exactly what a multi-speed transmission solves.

The biggest upgrade: our 5-speed electronic shifting kit

The single most transformative change you can make to this platform is our Bonnell 775 MX 5-Speed Electronic Shifting Upgrade Kit. It's a complete bolt-on rear wheel — not just a cassette swap — and it delivers three big wins. (We walk through the full install in our 5-speed upgrade guide.)

A true 5-speed transmission

Five gears finally give you both ends of the range: a low gear that crawls up steep climbs with authority, and a tall gear that lets the motor stretch out for real top speed. Because you can keep the motor spinning in its efficient RPM band instead of forcing one fixed ratio to do everything, you also get more range, cooler running temperatures and less drivetrain wear. One bike that climbs and hauls — no compromise.

An upgraded, purpose-built rear wheel

The kit ships as a fully built rear wheel engineered for the torque and abuse of a high-power MX bike — a stronger, more reliable foundation than the stock setup. There's no sourcing parts, guessing at compatibility, or hand-building a wheel: it bolts on and it's ready to ride.

Electronic shifting

Gear changes are handled electronically at the push of a button — fast, precise shifts even under power, without the finicky feel and constant adjustment of a mechanical derailleur. It's the kind of shift quality that makes a high-power build feel finished rather than cobbled together.

Want a complete upgrade? Step up to the Revolution MX or MX Pro

Upgrading a Bonnell makes a lot of sense — but if you want a massive performance leap rather than incremental gains, the smarter move is a purpose-built platform. Our Revolution MX and Revolution MX Pro are built from the ground up on a 78V platform and reach speeds of up to 50 mph — performance a modified Bonnell simply can't match.

On these bikes the entire system — battery, motor, controller, brakes and drivetrain — is engineered to work together at those speeds, so you get the top speed, climbing power and reliability that only come from a complete, integrated build. Put simply: the 5-speed kit gets far more out of the bike you already own, while the Revolution MX and MX Pro are the destination when you're ready for a full step up.

Other worthwhile Bonnell upgrades

• Brakes — faster builds need stronger, more consistent hydraulic stopping power.
• Controller — a higher-quality controller improves throttle response and unlocks the motor's range.
• Tires and cooling — match rubber to your terrain and keep the motor from overheating under load.

Whether you upgrade your Bonnell or step up to a Revolution MX, the goal is the same: stop chasing a single-speed compromise and get the right gear for every moment.

See the 5-speed upgrade kit →  |  Explore the Revolution MX Pro →