Converting a standard bicycle into an electric bike is the cheapest way to join the e-mobility revolution in 2026. For under £400, you can transform most bikes into capable commuters with a range of 30–50 miles per charge. The two dominant players in the UK conversion kit market are Swytch (known for its compact, integrated battery wheel) and Bafang (renowned for powerful mid-drive kits). This guide compares both kits on price, legality, ease of installation, and everyday usability.
Swytch Kit: The All-in-One Wheel Solution
The Swytch kit replaces your front wheel with a purpose-built e-wheel containing a 250W hub motor, and comes with a handlebar-mounted battery pack that connects via a proprietary connector. The latest Swytch Max+ kit costs £399 for the standard range version (36V, 7Ah battery). Installation takes roughly 30 minutes: you swap the wheel, attach the battery mount to your handlebars, connect the power cable, and zip-tie the speed sensor to your frame. The kit works with disc brakes, rim brakes, and most fork sizes from 20 to 29 inches. Range is advertised at 30 miles in Eco mode; real-world UK riding — with hills and wind — delivers closer to 22 miles.
Bafang BBS01B: The Mid-Drive Powerhouse
Bafang’s BBS01B is a 250W mid-drive motor kit that replaces your bottom bracket and drives the chain directly. The kit costs around £320–£380 depending on the supplier, but you must also budget for a battery (typically £120–£200 extra). Total cost lands at approximately £500, exceeding the £400 target. However, Bafang offers tremendous torque — 80 Nm compared to Swytch’s 35 Nm — making it ideal for steep hills and cargo bikes. Installation is more involved: you need a bottom bracket tool, a crank puller, and about 2–3 hours of mechanical work. The BBS01B is widely considered the gold standard for reliability; replacement parts are stocked by dozens of UK distributors.
UK Road Legality: What You Need to Know
In the UK, electric bikes must comply with the Electrically Assisted Pedal Cycles (EAPC) regulations to be road legal without registration or insurance. Key requirements: the motor must not exceed 250W, it must cut out at 25 km/h (15.5 mph), and the bike must have working pedals. Both Swytch and Bafang sell 250W versions that comply with these rules. However, Bafang also sells 750W and 1000W versions — fitting those to a street bike is illegal and can result in fines, points on your licence, and invalidated insurance. Always buy the 250W variant if you plan to ride on UK roads.
Which Kit Should You Buy?
If you want the simplest, quickest path to an e-bike and your daily commute is under 15 miles, the Swytch Max+ at £399 is the best value. No specialist tools, no complicated wiring, and the battery detaches in seconds for charging indoors. Choose the Bafang BBS01B if you are mechanically confident, need hill-climbing power, or want a system that will run for 10,000+ miles with proper maintenance. In both cases, budget an extra £50–£80 for a good helmet, lights, and a D-lock — saving money on the conversion should not mean compromising on safety.