Best Mountain Bike Electric Conversion Kit in 2025

Do you get tired on steep climbs with your mountain bike? Are your rides cut short because you lose energy too quickly? Do you wish you could go faster and enjoy longer rides without feeling worn out?

You can turn the bike you already own into an electric bike with a simple conversion kit. It costs less than buying a new e-bike and keeps the bike you already feel comfortable with. A good kit will give you the boost you need for hills, speed, and distance.

In this article, I will share the best mountain bike electric conversion kits available today. You will see what each kit is best for and the strengths and downsides of each option. I will also guide you on how to choose the right kit for your budget and riding style.

Quick Overview – Best Electric Conversion Kits for Mountain Bikes

Cytronex – Best Hub Motor Kit

Specification

• Motor: 250W front hub motor
  
• Battery: 198Wh bottle-style battery
  
• Weight: About 3.6 kg
  
• Range: Up to 30 miles per charge
  

The Cytronex hub motor kit is one of the lightest and most discreet conversion options available. Its bottle-style battery blends in with your bike frame and gives you electric assistance without making the bike look bulky.

Reasons to Buy

• Very lightweight and almost invisible once installed
  
• Easy installation, even for first-timers
  
• Great choice for commuting and shorter trail rides
  

Reasons to Avoid

• Limited range compared to larger battery kits
  
• Not powerful enough for long uphill climbs
  
• Price is on the higher side for the battery capacity
  

Buy it if

You want a lightweight, simple, and discreet hub motor kit that keeps your mountain bike looking natural. It’s a strong choice for daily city rides and leisure trips.

Don’t buy it if

You plan on riding long mountain trails or need serious hill-climbing power. In that case, the Bafang Mid-Drive Kit is a better pick for torque and performance.

Kirbebike 72V 4000W Extreme Performance – Best for Extreme Power

Specification

• Motor: 4000W high-performance hub motor
  
• Battery: 72V lithium-ion battery packs
  
• Weight: Around 10–12 kg with battery
  
• Range: 40–70 miles depending on riding style
  
• Top Speed: 55 MPH+
  

The Kirbebike 72V 4000W kit is built for extreme performance. With speeds reaching well over 55 MPH, it’s one of the most powerful conversion kits you can get for a mountain bike or fat tire bike. It delivers huge torque and acceleration, making it suitable only for advanced riders who want maximum power.

Reasons to Buy

• Incredible top speed and power
  
• Designed for extreme off-road and MTB use
  
• Strong build with heavy-duty components
  
• Suitable for fat tire and mountain bikes
  

Reasons to Avoid

• Very heavy compared to standard kits
  
• Overkill for casual commuting or short trips
  
• Not legal for road use in many regions
  

Buy it if

You want an extreme performance kit with maximum speed and torque for off-road, fat tire bikes, or thrill-seeking adventures.

Don’t buy it if

You’re looking for a kit for everyday commuting or city riding. In that case, the Cytronex or Swytch Kit is far more practical.

Bafang Front – Best Front Hub Option

Specification

• Motor: 250W–500W front hub motor (varies by model)
  
• Battery: Multiple options, usually 36V or 48V
  
• Weight: Around 6–7 kg including battery
  
• Range: 25–50 miles depending on battery choice
  

The Bafang Front kit is a simple front hub motor setup that makes converting your mountain bike straightforward. It delivers steady assistance, and with different battery options, you can match it to your riding needs and budget.

Reasons to Buy

• Affordable and widely available
  
• Easy to install with basic tools
  
• Works well for flat terrain and everyday use
  

Reasons to Avoid

• Heavier than some lightweight kits
  
• Less balanced weight distribution since the motor sits in the front wheel
  
• Not the best choice for aggressive mountain trails
  

Buy it if

You want a budget-friendly and easy-to-install kit that adds solid power for commuting or light trail rides. It’s great for riders who want a no-fuss entry into electric biking.

Don’t buy it if

You ride steep trails or need high torque for climbing hills. For that kind of terrain, the Bafang Mid-Drive Kit or TongSheng Mid-Drive Kit will give you stronger performance.

Zehus – Best for Smart Tech Features

Specification

• Motor: 250W rear hub motor (all-in-one unit)
  
• Battery: 173Wh integrated inside the hub
  
• Weight: Around 3 kg total
  
• Range: Up to 30 miles on a single charge
  

The Zehus kit stands out because it combines the motor, battery, and electronics in a single compact hub. It looks clean, requires almost no extra wiring, and even has Bluetooth connectivity so you can control settings straight from your phone.

Reasons to Buy

• Sleek all-in-one hub design
  
• Smart features with Bluetooth app control
  
• Regenerative braking that recharges the battery while you ride
  

Reasons to Avoid

• Limited range compared to larger external battery kits
  
• Higher price for the small capacity
  
• Not the strongest option for steep or long climbs
  

Buy it if

You want a modern, tech-driven conversion kit that is compact, stylish, and easy to manage through your smartphone. It’s ideal for riders who value design and convenience.

Don’t buy it if

You need long-distance range or powerful torque for off-road climbs. In that case, look at the Bafang Mid-Drive Kit or the Kirbebike 60V Rim Kit for tougher terrain.

Swytch – Best Lightweight Kit

Specification

• Motor: 250W front hub motor
  
• Battery: 98Wh (Eco) or 180Wh (Pro) compact battery pack
  
• Weight: About 3 kg total with the smaller battery
  
• Range: 15–30 miles depending on battery option
  

The Swytch kit is one of the most popular lightweight conversion kits on the market. It comes with a small battery pack that clips onto your handlebars, making it portable and simple to charge.

Reasons to Buy

• Very affordable compared to many other kits
  
• Lightweight and easy to carry battery
  
• Beginner friendly installation
  

Reasons to Avoid

• Range is shorter than bigger battery setups
  
• Front hub motor can feel less balanced
  
• Not built for heavy off-road riding
  

Buy it if

You want a budget-friendly, super light conversion kit that is perfect for commuting, leisure riding, or short city trips.

Don’t buy it if

You need long-distance endurance or plan to ride on rough mountain terrain. For those needs, the TongSheng Mid-Drive Kit or Pendix Kit will give you better performance.

Bafang BBS01 – Best for Hill Climbing

Specification

• Motor: 250W–350W mid-drive motor
  
• Battery: Usually paired with 36V packs (varies by seller)
  
• Weight: Around 4 kg without battery
  
• Range: 25–50 miles depending on battery choice
  

The Bafang BBS01 is a mid-drive motor kit that shines on climbs. It sits at the crank and uses the bike’s gears, giving you strong torque for hills and uneven terrain. It’s one of the most recommended kits for riders who want reliable climbing power.

Reasons to Buy

• Strong torque for hill climbing
  
• Mid-drive design feels natural and efficient
  
• Works well for mountain biking and rough terrain
  

Reasons to Avoid

• Installation is more complex than hub kits
  
• Slightly noisier than higher-end mid-drives
  
• Costs more than basic hub kits
  

Buy it if

You need a conversion kit that handles hills with ease and want more torque than a hub motor can provide. Perfect for mountain riders and off-road enthusiasts.

Don’t buy it if

You only ride flat city roads or want the easiest installation. In that case, a hub kit like the Swytch or Cytronex will serve you better.

Bafang Mid-Drive – Best Mid-Motor Kit

Specification

• Motor: 500W–1000W mid-drive motor (popular models BBS02/BBSHD)
  
• Battery: Usually paired with 48V or 52V packs
  
• Weight: Around 4.2–5 kg without battery
  
• Range: 30–70 miles depending on battery size
  

The Bafang Mid-Drive Kit is one of the most powerful and popular conversion kits available. It mounts at the crank, using your bike’s gears for efficient torque. This makes it a strong choice for mountain bikers who ride steep trails or need extra power for off-road adventures.

Reasons to Buy

• Excellent torque and climbing ability
  
• Works with a wide range of bikes
  
• High top speeds with larger battery packs
  
• Proven reliability and widely supported
  

Reasons to Avoid

• Installation requires more effort than hub kits
  
• Heavier than smaller, lightweight options
  
• Can put extra stress on bike chains and drivetrains
  

Buy it if

You want a powerful mid-drive motor that handles steep terrain and long rides with ease. It’s a great choice for mountain riders who need real performance and control.

Don’t buy it if

You just want a simple, lightweight kit for short commutes or casual city rides. In that case, the Swytch or Cytronex will fit your needs better.

Pendix – Best Premium Kit

Specification

• Motor: 250W–500W mid-drive motor
  
• Battery: 300Wh or 500Wh lithium-ion battery options
  
• Weight: Around 6.5 kg total
  
• Range: 25–65 miles depending on battery size
  

The Pendix kit is known for its premium German engineering and reliable build quality. It offers a very smooth power delivery, minimal noise, and durable components, making it one of the most trusted conversion kits for long-term use.

Reasons to Buy

• High-end build with German engineering
  
• Smooth and quiet performance
  
• Long-lasting reliability and durability
  
• Minimal maintenance required
  

Reasons to Avoid

• Higher cost compared to most kits
  
• Heavier than lightweight options
  
• Limited to moderate power compared to extreme kits
  

Buy it if

You want a premium, long-lasting mid-drive kit that delivers smooth and reliable assistance for years. It’s ideal for riders who value quality and durability above everything else.

Don’t buy it if

You’re on a tight budget or looking for maximum power. Kits like the Swytch for affordability or Kirbebike 72V for extreme performance may be a better fit.

TongSheng Mid-Drive Kit with Battery – Best for Balanced Performance

Specification

• Motor: 250W–500W mid-drive motor (TSDZ2 model is most common)
  
• Battery: Often sold with 36V or 48V packs
  
• Weight: Around 3.6–4 kg without battery
  
• Range: 25–60 miles depending on battery choice
  

The TongSheng mid-drive kit has become a popular choice because it balances power, price, and usability. It features a torque sensor, which means the motor gives assistance that feels natural and smooth. This makes it a good option for riders who want more than a hub motor but don’t want to overspend.

Reasons to Buy

• Affordable mid-drive kit with solid performance
  
• Torque sensor provides a natural pedaling feel
  
• Lighter than some other mid-drive options
  
• Includes a battery with most kits
  

Reasons to Avoid

• Not as powerful as the Bafang mid-drive kits
  
• Installation is more complex than hub motors
  
• Can wear drivetrain parts faster if not maintained
  

Buy it if

You want a balanced mid-drive conversion kit that offers natural pedaling and good performance without breaking the bank. A strong choice for regular riders who want comfort and reliability.

Don’t buy it if

You’re chasing extreme performance or speed. If that’s your goal, the Kirbebike 72V Kit or Bafang Mid-Drive would be better fits.

Gboost Friction Drive – Best for Minimalist Riders

Specification

• Motor: 250W–450W friction drive motor
  
• Battery: 200Wh–400Wh lithium-ion packs available
  
• Weight: About 3 kg total
  
• Range: 20–40 miles depending on setup
  

The Gboost kit is different from most others because it uses a friction drive system. Instead of sitting in the hub or crank, it presses a roller against the bike tire to provide power. This makes it compact, easy to install, and simple to remove when not in use.

Reasons to Buy

• Lightweight and compact design
  
• Quick installation and removal
  
• Minimal changes to the bike frame
  
• Quiet operation when tuned properly
  

Reasons to Avoid

• Less efficient than hub or mid-drive systems
  
• Tire wear can increase over time
  
• Not ideal for long-distance rides or heavy off-road use
  

Buy it if

You want a minimalist and removable conversion kit that gives you a small power boost for city rides or light commuting. Perfect for riders who want occasional electric help without committing to a full conversion.

Don’t buy it if

You need a long-lasting range or plan to tackle mountain trails. In that case, the TongSheng Mid-Drive Kit or Bafang Mid-Drive Kit will give you more consistent performance.

Skarper – Best Plug-and-Play Conversion

Specification

• Motor: 250W disc brake drive unit
  
• Battery: Integrated within the motor module
  
• Weight: Around 3 kg total
  
• Range: 20–30 miles depending on terrain
  

The Skarper kit is one of the newest innovations in the conversion market. Instead of attaching to the hub or crank, it clips onto a special disk brake rotor, making it one of the easiest plug-and-play systems available. Riders can install or remove it in seconds, which adds a lot of convenience.

Reasons to Buy

• Extremely simple installation and removal
  
• Lightweight and compact design
  
• Modern, innovative approach to conversion
  
• No major changes required to the bike frame
  

Reasons to Avoid

• Higher price compared to its range and power
  
• Requires a special rotor for compatibility
  
• Limited availability since it’s still new in the market
  

Buy it if

You want a quick and easy plug-and-play solution that doesn’t require technical installation. It’s perfect for casual riders who want electric assistance without committing to a permanent setup.

Don’t buy it if

You need more range or plan to ride tough trails. For that, the Bafang Mid-Drive Kit or Kirbebike 60V Rim Kit will offer more power and durability.

Kirbebike 60V 2500W–3000W MTX Rim Kit – Best for Off-Road & Fat Tire Bikes

Specification

• Motor: 2500W–3000W MTX rim motor
  
• Battery: 60V lithium-ion battery packs
  
• Weight: About 9–11 kg with battery
  
• Range: 35–60 miles depending on use
  
• Top Speed: 40–45 MPH
  

The Kirbebike 60V MTX Rim Kit is built for riders who need rugged performance on mountain and fat tire bikes. It combines strong torque with solid top speeds, making it perfect for steep climbs, rough trails, and off-road adventures where durability matters.

Reasons to Buy

• Powerful motor designed for tough terrain
  
• Great match for fat tire and MTB frames
  
• Strong balance of speed and torque
  
• High-quality components built for off-road stress
  

Reasons to Avoid

• Heavier than smaller mid-drive or hub kits
  
• Still too powerful for legal road use in many areas
  
• Installation requires more effort and compatible bike setup
  

Buy it if

You want a rugged conversion kit for off-road riding that balances speed, torque, and durability. Perfect for fat tire bikes and mountain bikers who ride in rough conditions.

Don’t buy it if

You need a kit for everyday commuting or lightweight use. For those needs, the Swytch Kit or TongSheng Mid-Drive Kit will give you better practicality.

Side-by-Side Specification Comparison

How to Choose the Best Electric Bike Conversion Kit

Finding the right conversion kit depends on your riding style, terrain, and budget. Not every kit suits every rider, so knowing what to look for helps you avoid mistakes and choose a kit you’ll enjoy using.

Motor Type

The motor is the heart of your conversion kit.

• Hub motors (like Cytronex or Swytch) are simple, affordable, and great for city riding.
  
• Mid-drive motors (like Bafang or TongSheng) give better torque for climbing hills and off-road riding.
  
• Friction drive systems (like Gboost) are light and removable, good for riders who want a minimalist setup.
  

If you ride mostly on flat roads, a hub motor works fine. If you take on hills or mountain trails, a mid-drive is the better choice.

Battery and Range

Battery size affects how far you can ride. Smaller packs like the Swytch Eco are fine for short trips, while larger packs like the Kirbebike 72V handle long rides and extreme performance. Always check the battery voltage and capacity (Wh) before buying.

Think about how many miles you ride in a typical day and pick a kit that covers it with some extra buffer.

Installation Difficulty

Some kits install in minutes, while others take more effort.

• Easiest installs: Swytch, Cytronex, Skarper
  
• Moderate installs: Bafang Front, Gboost
  
• More advanced installs: Bafang Mid-Drive, TongSheng, Kirbebike kits
  

If you are new to bike mechanics, start with a plug-and-play kit. For skilled riders, a mid-drive installation might be worth the extra effort.

Weight and Balance

Lighter kits like Swytch or Zehus make your bike easier to handle. Heavier kits like the Kirbebike series add more power but also more weight. Always consider how much weight you’re comfortable with when lifting or carrying your bike.

Budget vs Performance

Prices vary widely, from budget-friendly kits like Swytch (£449) to premium options like Pendix (£1,399). High-power kits like Kirbebike give extreme performance but are overkill for casual rides.

Choose a kit that matches how you actually ride, not just the most powerful one on the market.

What Types of E-Bike Conversion Kits Are There?

Not all conversion kits work the same way. The type you choose will affect performance, price, and how natural the ride feels. Here are the main options you’ll find on the market.

Hub Motor Kits

Hub motors are the most common and affordable option. They replace either the front or rear wheel with a motorized hub.

• Front hub motors are easy to install and good for flat roads.
  
• Rear hub motors give better traction but take a bit more work to fit.

Example kits: Cytronex, Swytch, Bafang Front, Zehus

Mid-Drive Motor Kits

Mid-drive motors sit at the crank and power the bike through its gears. This gives more torque and efficiency on hills and off-road rides. They feel more natural because the motor works with your pedaling.
Example kits: Bafang BBS01, Bafang Mid-Drive, Pendix, TongSheng

Friction Drive Kits

These kits use a roller that presses against the tire to provide power. They are compact, lightweight, and can be removed quickly. The trade-off is less efficiency and faster tire wear.
Example kit: Gboost Friction Drive

Rim Drive and Extreme Power Kits

Rim drive kits and high-power hub motors push performance to the extreme. They are designed for mountain bikes and fat tire bikes, often hitting very high speeds. These are not road legal in many areas but are popular with thrill-seekers.
Example kits: Kirbebike 72V 4000W, Kirbebike 60V MTX Rim Kit

Frequently Asked Questions

Is it worth converting a mountain bike to electric?

Yes, it can save you money compared to buying a new e-bike. A good kit gives you extra power for hills, speed, and longer rides while keeping your favorite bike.

How fast can an electric conversion kit make my mountain bike go?

Most legal kits reach 15–28 MPH. High-power kits like the Kirbebike 72V can go over 55 MPH, but they are usually for off-road use only.

How long does it take to install a conversion kit?

Easy kits like Swytch or Skarper can be fitted in under an hour. More advanced mid-drive kits like Bafang Mid-Drive may take a few hours and some bike mechanic skills.

Do I need special tools to install a kit?

Basic tools are enough for hub motors. Mid-drive kits may require crank pullers or bottom bracket tools. Most brands provide installation guides or video tutorials.

Which kit is best for off-road and hill climbing?

For climbing and trails, mid-drives like the Bafang BBS01 or TongSheng are excellent. For extreme power off-road, the Kirbebike 60V MTX Rim Kit is a strong choice.

What’s the average cost of a good mountain bike conversion kit?

Most quality kits cost between £500 and £1,400. Budget-friendly options like Swytch start around £449, while premium builds like Pendix can reach £1,399 or more.

Final Thoughts

Converting your mountain bike into an e-bike is one of the smartest ways to get more from the bike you already love. Instead of spending thousands on a brand-new electric bike, a conversion kit gives you extra speed, torque, and range at a fraction of the cost.

The right kit depends on your riding style and budget. Lightweight hub kits like Swytch and Cytronex are perfect for commuting, while mid-drives such as the Bafang BBS01 or TongSheng give you climbing power and natural pedaling. If you want premium reliability, Pendix is a strong choice, and for thrill-seekers, Kirbebike’s high-power kits deliver unmatched performance.

Ready to upgrade your ride? Choose the conversion kit that matches your needs and start enjoying longer, faster, and easier rides today.

At the end of the day, the best electric conversion kit for your mountain bike is the one that fits your terrain, your budget, and your goals. Take the first step, pick your kit, and turn your mountain bike into a powerful e-bike that makes every ride more exciting.