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Guides • Conversion Kits • Pricing
How Much Does an E-Bike Conversion Cost in the UK? (2026 Price Guide)
Quick answer: A basic 250W hub motor conversion with a modest battery starts from around £300–£450 in parts. A Bafang mid drive kit with a decent battery typically runs £550–£900. High-power off-road builds (1500W+) with a large battery can reach £900–£1,300+. Add roughly £80–£180 for professional fitting if you're not doing it yourself. This guide breaks down exactly where that money goes.
About this guide: These figures are based on the kits and batteries we actually stock and fit at the All4eBikes Cardiff workshop, not generic estimates. Prices are correct at the time of writing and can change — always check current pricing on the relevant product page before budgeting. If you're specifically weighing up hub motor vs mid drive on cost alone, our total cost of ownership comparison goes deeper on that specific decision; this page covers the full build cost across the whole range.
Contents
What You're Actually Paying For
An e-bike conversion cost breaks down into three main components: the motor kit (motor, controller, display, and cabling), the battery, and fitting if you're not doing the install yourself. Most online cost guides only quote the motor kit price and leave out the battery and fitting, which is why a quoted "£250 conversion kit" can end up costing considerably more once you've built a complete, ridable bike.
Cost by Build Tier
| Build tier | Typical total cost* | What you get |
|---|---|---|
| Entry-level road-legal | £300–£450 | 250W hub motor, 36V battery (10–13Ah), basic display |
| Bafang mid drive, everyday use | £550–£900 | BBS01B or BBS02B motor, 48V battery (17.5–20Ah) |
| High-power off-road | £700–£1,000 | 1500–3000W hub motor or BBSHD, 48V/52V battery |
| Maximum performance build | £900–£1,300+ | 3000W+ hub motor, 72V high-capacity battery, upgraded controller |
*Parts cost only, based on typical UK retail pricing in mid-2026. Fitting cost is separate — see below.
Motor Kit Costs: Hub vs Mid Drive
Hub motor kits are generally the cheaper starting point, particularly at 250W, since the mechanical design is simpler and doesn't require the more expensive planetary gearbox and torque sensor integration a mid drive uses. As power climbs, the price gap narrows — a high-power hub motor kit (1500W+) can cost a similar amount to a mid drive once you factor in the stronger controller and wheel build required.
Mid drive kits like the Bafang range command a premium over an equivalent-wattage hub motor because you're paying for the gear-multiplication advantage and better weight distribution, not just raw wattage. For a direct look at which Bafang model suits your budget, see our BBS01B vs BBS02B comparison.
Battery Costs by Voltage and Capacity
The battery is often the single most expensive component in a conversion, and it's the part most budget cost guides underquote. Cost scales with both voltage and capacity (Ah) — doubling either roughly doubles the cell count, and therefore the price.
| Battery spec | Typical price range |
|---|---|
| 36V, 10–13Ah | £180–£260 |
| 48V, 17.5–20Ah | £280–£400 |
| 52V, 20–28Ah | £350–£520 |
| 72V, 20Ah+ high-discharge | £450–£650+ |
Browse the full eBike battery range to compare current pricing across voltage and capacity options directly.
DIY vs Professional Fitting Cost
Fitting a hub motor is the more DIY-friendly job — it's mostly a wheel swap, and many confident home mechanics manage it with basic tools in an afternoon. A mid drive install is more involved, since it means removing your existing bottom bracket and crankset and correctly setting chainline and torque, which is why more riders opt for professional fitting on a mid drive build.
Professional fitting at our Cardiff workshop typically runs £80–£120 for a hub motor and £120–£180 for a mid drive, depending on the bike and any additional work needed. For a closer look at what's involved either way, see our guide on DIY vs professional conversion kit fitting.
Hidden and Easy-to-Miss Costs
Costs riders often forget to budget for
- Upgraded brakes if your current setup isn't rated for the extra speed and weight (see our hub motor servicing page for what we typically check)
- A torque arm for hub motor kits, to prevent the axle spinning in the dropout under load
- A charger, if one isn't included with your chosen battery
- Fitting labour, if you're not doing the install yourself
Costs that are usually one-off, not recurring
- The motor kit and battery — both last several years of normal use
- Any frame adapter or bracket needed for an unusual frame shape
- Initial setup and configuration time, whether DIY or professional
Where You Can Genuinely Save Money
1
Choose the wattage your riding actually needs
The single biggest way to overspend is buying more wattage than your terrain and use case call for. A 250W or 750W kit costs meaningfully less than a 1500W+ kit, and for most commuting and moderate off-road use, it's genuinely enough.
2
Match battery capacity to your real riding distance
Buying a much bigger battery than your typical ride distance requires just adds cost and weight. Work out your realistic round-trip mileage first, then size the battery to that with a sensible margin.
3
Fit it yourself if you're comfortable with basic bike mechanics
A hub motor kit in particular is a realistic DIY job for most confident home mechanics, saving the £80–£120 fitting cost.
4
Get advice before you buy, not after
Message us on WhatsApp with your budget and riding plans. We'll help you spend on the parts that matter for your use case and skip the ones that don't.
Visit us: 2 Beresford Road Lane, Cardiff, CF24 1QU
Hours: Mon–Fri 11am–6pm • Sat 11am–3pm • Sun closed
Hours: Mon–Fri 11am–6pm • Sat 11am–3pm • Sun closed
FAQ
Is it cheaper to convert a bike than buy a factory e-bike?
Usually, yes — especially if you already own a good-quality bike you're happy to convert. A full conversion typically costs several hundred pounds less than an equivalent factory-built e-bike with comparable motor power and battery capacity, since you're not paying for a complete new frame, wheels, and finishing kit.
What's the cheapest way to convert a bike to electric in the UK?
A 250W hub motor kit with a modest 36V battery, fitted yourself, is the lowest realistic total cost while still being genuinely road-legal and usable. Going any cheaper than this range usually means an unbranded kit with weaker components and little to no support if something goes wrong.
Does a Bafang mid drive really cost that much more than a hub motor?
At the entry level, yes, there's a real price gap. At the higher-power end the gap narrows, since a strong hub motor kit needs a beefier controller and wheel build to match. The extra mid drive cost buys you gear-multiplication and better weight distribution, which matters more on hilly or off-road terrain than on a flat commute.
Are there ongoing costs after the initial conversion?
Running costs are low — mainly electricity to charge the battery, which costs only a few pence per full charge. Occasional servicing (brake pads, chain wear, and eventually battery replacement after several years of use) is the main ongoing cost, similar to owning any bike.
Should I buy the motor and battery separately or as a bundle?
A bundle is usually slightly cheaper than buying the motor and battery separately, and guarantees the voltage and connector match without you needing to check compatibility yourself. It's the simpler option for most first-time conversions.
Want a straight answer on what your conversion would actually cost? Message George on WhatsApp with your bike and budget — we'll give you a realistic total, not just a headline motor price.
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