Convert Your Existing Bike for Less Than a New E-Bike
A quality e-bike conversion kit transforms your existing bicycle into an electric one for $300–1,200 — often far less than buying a new e-bike of equivalent quality. If you already own a bicycle you love (the geometry fits you, you’ve tuned the components), converting it preserves what works and adds electric assist. This guide covers the main kit types, which bikes they work on, and the best options for each approach.
Types of E-Bike Conversion Kits
Rear Hub Motor Kits (Most Popular)
Replace the rear wheel with a motorized wheel. Motor sits in the hub. Installation: remove old rear wheel, install new motorized wheel, mount battery and controller, wire everything together. Difficulty: 3–4 hours for a mechanically capable person. Works with most bikes (verify axle width, dropout type). Best for: road bikes, hybrid bikes, commuter bikes.
Front Hub Motor Kits (Simplest)
Same as rear hub but installs at the front. Simpler installation (front wheels are easier to work with). Disadvantage: front motor can affect steering weight and traction on hills/wet surfaces. Best for: quick conversions where simplicity is paramount.
Mid-Drive Kits
Motor replaces the bottom bracket (crankset area). Uses the bike’s existing gears — more efficient on hills. Better weight distribution (motor weight is centered). Installation is more complex. Compatible with fewer frame types (requires specific bottom bracket standards). Best for: mountain bikes, touring bikes, bikes used on hilly terrain.
All-in-One Smart Wheels (Copenhagen Wheel, FlyKly)
A complete wheel where motor, battery, and controller are all integrated inside a single oversized hub. Install by replacing the wheel. The cleanest-looking conversion. Limited battery capacity (battery fits inside the hub). Best for: style-conscious urban commuters who want minimal visible components.
Best E-Bike Conversion Kits 2025
1. Bafang BBS02B 750W — Best Mid-Drive Kit
Price: $350–500 | Power: 750W (1,000W peak) | Compatibility: 68–73mm BSA bottom bracket
The Bafang BBS02B is the market standard for mid-drive conversion kits. 750W motor with 80Nm of torque handles hills effectively. The torque sensor (integrated in the motor) provides natural pedal assist. Works with the bike’s existing gears for efficient hill climbing. Installation requires removing the crankset and bottom bracket — a job for someone comfortable with bike mechanics or willing to learn. The BBS02B is sold by multiple vendors (Lunacycle, EM3EV, BAFANG directly) at different prices and battery options. 48V 13Ah battery ($200–350 extra) provides 30–50 miles of range. Best for: mountain bikes, touring bikes, and commuters on hilly terrain.
2. Swytch Universal Wheel Kit — Best Simple Hub Kit
Price: $699 (Max version) | Power: 250W | Battery: 130Wh (packed into handlebar bag)
Swytch takes a unique approach: the battery is in a compact pack that mounts to the handlebar, and the hub motor replaces your front wheel. The entire kit installs in under 60 minutes with minimal tools. The 250W motor is modest — adequate for flat terrain and mild hills. 130Wh battery provides 15–30 miles of range. The kit is removable — attach it for commuting, remove it for weekend recreational riding without the extra weight. Best for: urban commuters who want a quick, reversible conversion with minimal installation complexity.
3. Bafang BBSHD 1000W — Best High-Power Mid-Drive
Price: $450–700 | Power: 1,000W continuous (1,500W peak) | Torque: 120Nm
The BBSHD is Bafang’s high-power mid-drive — the motor choice for riders who need serious hill-climbing ability or want more performance than the BBS02B delivers. 120Nm of torque and 1,000W continuous handles steep grades, heavy riders, and cargo-loaded bikes. The higher power requires a bike frame that can handle the stress — steel or aluminum frames with solid welds; carbon fiber frames are generally not recommended. Popular for cargo bike conversions and mountain bike conversions where maximum torque matters. Best for: high-demand use cases including cargo hauling, steep terrain, or performance-oriented builds.
4. Lectric XP DIY Kit — Best Budget Hub Kit
Price: $299 | Power: 500W | Compatibility: Standard 135mm rear dropout
Lectric offers their hub motor system as a standalone conversion kit — the same motor and battery that goes into their best-selling XP e-bike. At $299, it’s the most affordable quality conversion kit available. Compatible with most bikes with 135mm rear dropout spacing. Includes battery, motor wheel, controller, display, and throttle. Installation takes 2–3 hours. Best for: budget-conscious conversions on standard commuter or hybrid bikes.
5. Copenhagen Wheel — Best Stealth Smart Wheel
Price: $1,499 | Power: 250W | Battery: 375Wh (in hub) | App-connected
The Copenhagen Wheel (made by Superpedestrian) is the most sophisticated single-wheel e-bike conversion. The entire electric system — motor, battery, sensors, controller, Bluetooth — lives inside an oversized rear wheel hub. From the front, the bike looks like a regular bike with a slightly thick rear hub. The Superpedestrian app manages assist levels, diagnostics, and even anti-theft features. At $1,499, it’s the most expensive kit on this list — but the integration and stealth aesthetics are unmatched. Range is 30–60 miles depending on terrain and assist level. Best for: style-conscious urban riders who want invisible integration and are willing to pay premium for it.
What Bike Works for Conversion?
- Hub motor kits: Most bikes with standard dropout widths (135mm rear, 100mm front) work. Mountain bikes with thru-axles need specific adapters or are incompatible with many kits.
- Mid-drive kits (Bafang BBS02B/BBSHD): Require 68mm or 73mm threaded bottom bracket shells. Road bikes, hybrids, and many mountain bikes qualify. 1-piece cranks, press-fit bottom brackets, and some external bearing types require adapters or are incompatible.
- Weight capacity: Your frame needs to handle its own weight plus motor, battery, and rider. Most aluminum frames rated for 250+ lbs are fine. Inspect the frame for cracks or damage before converting.
Is Conversion Right for You?
| Convert Your Bike If… | Buy a New E-Bike If… |
|---|---|
| You own a high-quality bike that fits well | Your current bike is low-quality or doesn’t fit |
| You’re comfortable with basic bike mechanics | You want plug-and-play simplicity |
| You want to save money vs new e-bike | You want a warranty covering the complete system |
| You want to keep specific components | You need a step-through or specific geometry |