The best electric bike conversion kits and how to fit them

With one the best electric bike conversion kits you can add power to your own bike at the fraction of the cost of a full machine

Included in this guide:

Ebikes are soaring in popularity – and for good reason. The best electric bikes replace a car for running errands around town and greatly increase the distances it’s possible to commute by bike. An ebike can also be a great tool for boosting your fitness, whether that’s enabling you to ride with a greater range of people or offering the motivation of a greater range of roads to explore.

But is an ebike worth it,? As the best electric bike conversion kits promise to add power to an 'analogue' bike for a lot less than a full ebike, some would argue not. 

In this guide we’ll take you though the surprisingly broad range of benefits an ebike conversion kit has to offer and – most importantly – how to perform an ebike conversion. For a walk through on how to do it, you can check out the video above or read on for a step by step guide – it genuinely is so much simpler than you would think. 

The best ebike conversion kits

Bafang front hub motor kit

(Image credit: Bafang)

Bafang front hub motor kit

Front hub motor from a brand with a solid reputation

Capacity : 11.6 – 17.5Ah options (45km/28mi – 68/km42mi)
Torque: 65Nm
Compatibility: Disc brake with a quick release axle
Wheel sizes: 20", 26", 27.5"/650b, 28"/700c
Reasons to buy
+Good value+Less bulky
Reasons to avoid
-Could do with better instructions

Bafang is a well established maker of electric bike motors and offers a front hub based motor, if you’re not a fan of the bulky profile a mid motor conversion system creates. You can buy this kit without a battery – although why would you? – but if you sensibly also opt for a power-pack there's a choice of amp hours, and you can select either a downtube or a rear-rack mounted version. 

The setup follows the same principles as most front-wheel ebike conversions. First you need to set up the wheel with a disc rotor, tyre and inner tube and install that into the bike. Then attach the cadence sensor – so it can tell when you're pedalling and need assistance – then attach the battery and the LCD display and you're essentially good to go!

It's worth bearing in mind that although this conversion kit comes in many different wheel sizes, it is only compatible with bikes that have a front disc brake and a Quick-Release axle. If your disc brake bike is a newer, more expensive model, it might not be compatible, so worth checking first.

Remember, that in the UK ebikes are not permitted to have a power output of more than 250w and shouldn't propel the bike when it's travelling more than 15.5mph – you'll have to make sure you select the right model with the relevant limitations.

Bafang mid drive

(Image credit: Bafang)

Bafang Mid Motor Kit

Best electric bike conversion kit for riding off road

Capacity: Battery sold separately
Torque: 80Nm
Compatibility: Only alloy bikes and bottom brackets 68–73mm
Reasons to buy
+Capable off road+Keep your current wheels+High torque
Reasons to avoid
-Low slung motor doesn’t offer much clearance under bottom bracket for large obstacles-Battery sold separately

A mid-motor drive system offers a number of benefits over hub-driven conversion kits. With the power delivered at the cranks it can produce more torque, making it more effective on particularly steep and bumpy terrain. 

Another perk is that the compatibility is much greater – no concern about wheel diameters, hub widths, axle standards and brake type. No matter whether you're running rim brakes or disc, quick release or thru-axle, the crank driven system is compatible with all.

The only proviso is that the frame material must be alloy and the bottom bracket width is 68–73mm – but that covers most bikes you're likely to be fitting this system to.

There are a few aspects to be aware of, the first being that this system doesn't include a battery and that typically makes up about half the cost of a conversion kit. Finding an ebike battery is quite straightforward with many being sold on Amazon, with Green Cell being among those we'd recommend.

Just make sure to get a 36V one for this motor as a higher voltage can damage it. Also you should be aware that capacity of 10Ah will give you a range of about 29km / 18mi, while a capacity of 18Ah typically gives about 53km / 33mi – so be sure to factor in the distances you're planning on riding. 

Swytch conversion kit

(Image credit: Swytch)

Swytch Universal eBike Conversion Kit

Best ebike conversion kit for simple fitting

Capacity : 7Ah (21km /13mi or up to 50km/30mi when ridden economically))
Torque: 40Nm
Compatibility: : Rim brake and disc brake with 100mm quick release dropouts
Wheel sizes: Each wheel is custom built – specify your required size at checkout (Bromptons also catered for)
Reasons to buy
+Very simple to set up+Sleek design+Relatively lightweight
Reasons to avoid
-Shorter range-Often sold out

The Swytch system is one of the simplest conversion kits to fit out there and yet is still amongst the cheapest. The motor sits in the front hub and is pretty discreet, while the battery pack sits in a bag that connects to the front of your handlebars.

This setup makes it one of the most straightforward front-hub conversion kits currently out there, although it does mean the battery size is a little lower than other systems which mount the battery in the main triangle or in a rear rack. 

Used moderately heavily, you'll likely only get 21km /13mi out of one charge, although this can be as high as 50km/30mi with more efficient use of the assist and on flatter terrain. That said, if you are using this system for commuting, it is very easy to take off the battery pack and bring it in with you to charge – it takes as little as 3 hours.

Great customer support makes this one of the best kits for people who are new to working on their bike and who aren't familiar with electrics. And even if you do have a strong background in both those areas, a simple system is always appreciated.

Rubbee X Wireless Electric Bicycle Conversion Kit

(Image credit: Rubbee )

Rubbee X Wireless Electric Bicycle Conversion Kit

Best conversion kit for speed of setup

Capacity : 2.6Ah (about 16km / 10mi in eco mode)
Torque: N/A
Compatibility: Most bike without heavily treaded tyres
Reasons to buy
+All-in-one unit very quick and easy to fit+Compatible with huge range of bikes+Relatively cheap+Regenerative braking+Can be removed in seconds
Reasons to avoid
-Lower range-Extra wear on tyre

This radically different approach from Rubbee makes for an ebike conversion with much fewer parts. The battery and motor are housed in a single unit which powers the bike directly turning the rear wheel with its integrated roller.

Not only is the initial installation notably fast and easy, the quick release system means that you can take off the unit for rides that you don't wish to be assisted on. At 2.8kg, it doesn't add much weight to that of the bike, making the bike easier to handle.

The range of this model is quite low, limited to Eco mode it only offers a range of 16km / 10mi – although taking the device off to charge at the other end is easy to do and it only takes an hour to top up. There is the option to increase your range by buying additional battery modules that fit into the base unit. 

Up to three can be accommodated, which in turn increases the maximum range to 48km / 30mi, or around 23km / 14mi with moderately heavy use. However, unlike many other ebike systems, the Rubbee X supports regenerative braking, allowing you to scrub back some power on the descents.

TongSheng mid drive motor

(Image credit: TongSheng)

TongSheng Mid Drive Motor

Best mid drive system for weight

Capacity : Battery sold separately
Torque: 80nm
Compatibility: Only alloy bikes and bottom brackets 68–73mm
Reasons to buy
+Lightweight for the power output +Compatible with a wide range of bike designs+Better ground clearance
Reasons to avoid
-Battery must be bought separately

Like the Bafang mid drive system, the TongSheng offers the same benefits of compatibility with a wide range of bike designs and a high torque for steep hills and off-road terrain. However, the TongSheng mid drive does manage to be a little lighter than the Bafang for approximately the same power. 

This model doesn't come with a battery included, so you'll have to source your own 36v item. As a rule of thumb, around 10Ah will give a range of 29km / 18mi, whereas going up to 18Ah will typically give around 53km / 33mi, so be sure to factor that in when you're making your choice. 

There's a huge range being sold on Amazon, but Green Cell is a particular brand we'd recommend.

The fitting procedure follows the same lines as most mid drive systems, with your crank and chainring replaced by the one provided in the kit, an LCD display for attaching to your handlebars and the need for a battery to be hooked up to the motor.

How to convert your bike to an ebike in four steps

1. Swap the tyre and tube


(Image credit: Future)

Firstly, remove the tyre and tube from your current front wheel and then install them on the new wheel from the kit. Make sure to check if the tyre is directional, if it is, ensure that the tyre is mounted so that the cable sticking out of the hub is on the left-hand side (non-driveside) when the wheel is installed in the bike – otherwise it’ll be powered in the opposite direction to your direction of travel!

To swap the tyre and tube over, you will need some tyre levers and a pump. If you want to go over how to do these, we have a guide that can be accessed here.

Final points are to do up the nuts on the wheel’s axle to keep it firmly in place in the forks and to check that the brakes are correctly adjusted for the new wheel. If you’re unsure how to do that, we have another guide here.

2. Attach the bracket to the handlebars


(Image credit: Future)

There is a strap that needs to be attached to the bars to keep the bracket in place and stop it rotating around. There are also some adaptors included in the kit which can be used if your handlebars are a little skinnier. 

But essentially all that’s needed to be done here is a couple of screws to clamp the bracket tightly to the bars.

3. Attach magnet disc and sensor


(Image credit: Future)

The magnet disc has a split design so it can just clip around the inside of the left (non-driveside crank) and is then held in place by its retention ring. Next, stick the sensor on the frame directly in line with the magnets – this will ensure that the sensor can tell when the cranks are moving.

4. Plug in the cables


(Image credit: Future)

The thickest one is the main power cable and that just needs to be plugged into the cable extending from the hub. The other orange cable attaches to the cadence sensor and this just needs plugging in as well.

It’s then a good idea to use come cable ties to tidy up the lengths of the cables a little bit, so they aren’t flapping about and risk getting caught on the spokes or on the cranks.

The blue cables, you don’t need to worry about, these are for an optional brake sensor upgrade kit.

Why convert your bike to an e-bike?

How much does it cost to convert a bike to an e-bike?

Prices vary depending on the type of conversion kit and the size of the battery. To give a rough band, you can expect to pay a total of between £500 and £800 from a reputable brand, but there will be outliers at either end.

Is it worth converting a bike to an e-bike?

There are many reasons to upgrade your bike to offer a little e-assistance. On the one hand, it can greatly increase the utility of your bike, enabling you to replace short car journeys – such as though around town, to the shops, or to work – with going by bike instead.

It’s a lot more environmentally friendly getting about on two wheels than in a two-ton metal box. It can also save you time – bikes are able to take more direct routes and are less affected by traffic, as well as eliminating the need to search for a parking space at the other end.

But beyond just their practical benefits, e-bikes can also be a potent tool for boosting your fitness. Consistency is key when it comes to exercise, so making commitments with friends is a great way to ensure you’re heading out the door. Previously, differing fitness levels could make it difficult to find a riding partner but with an e-bike levelling the playing field, getting in a productive workout (for both of you) with a friend is much easier to do.

Added to that, an e-bike can be much more motivating in that it opens up a far greater range of roads than you’d be able to access just under the power of your own two legs. Exploring new roads is part of the fun of riding a bike and an e-bike can help preserve that.

Can you convert a regular bike to an e-bike?

Most bikes can be converted to an e-bike – it just requires getting the matching the right conversion kit to the match the specification.

For conversion kits where the motor is located at the wheel’s hub, you’ll need to consider the wheel’s diameter, the width and axle standard of the hub and whether it uses rim or disc brakes. For instance, a 700c (AKA, 28”) disc brake wheel with a 100mm wide quick-release hub is a relatively common spec. Once you’ve determined what type of wheel you need, the conversion is quite a straightforward process

Crank driven systems are generally easier in terms of determining compatibility; the requirements are typically just an alloy frame and a bottom bracket width of between 68 and 73mm – which is the standard for all road and mountain bikes, it’s only specialist bikes that have a different spacing there. In replacing the crankset, these systems are a bit more involved to fit than a hub system, but still well within the remit of a home mechanic.

Other kits, such as those that directly drive the rear tyre, have almost universal compatibility – provided your tyres aren’t too heavily treaded.

Are electric bike conversion kits any good?

You won’t be getting the very best motors and the largest, seamlessly integrated batteries with an e-bike conversion kit. But with that said, e-bike conversion kits are much cheaper than purchasing a whole new e-bike and they do deliver much of the same benefits.

Converted e-bikes are great for commuting and utility cycling, giving that extra boost to help flatten hills, motor along the flat and lug about heavy loads. E-bike conversions are also good for leisure cycling, helping to moderate your effort level as needed and greatly extending the range you can explore.

For more specialist utility needs, buying a new cargo e-bike would help boost your carrying capacity and range. Equally, for the aesthetically conscious, the latest breed of e-road bikes are almost indistinguishable to a non-powered bike at first glance. Then again, both those options are much more expensive than a conversion.

Rob Spedding

Rob has been Content Director of Cycling Weekly - and stablemates Bikeperfect, and MBR - since May 2021. Before that he spent two years in similar role at Bikeradar, which followed 12-years as Editor-in-chief of Cycling Plus magazine and eight years at Runner's World. In his time as a cycling journalist he's ridden from London to Paris at least twice, London to Bristol once, completed the Fred Whitton Challenge, L'Etape du Tour and Maratona dles Dolomites. He's also jumped into the broom-wagon at La Marmotte and Oetzaler Radmarathon.