DIY Upgrade: Best E-Bike Conversion Kits

Written by: Rémy Rossi | March 7, 2025 | Time to read 11 min

These recommended e-Bike conversion kits are well-designed systems that impress on compatibility, performance, and value. Riding up hilly terrain demands top-quality motors and batteries that can withstand the extra effort.

The e-Bike conversion kits featured below steer well clear of certain, not-to-be-named online wholesale marketplaces. The products come from trusted brands with a track record of many successful e-Bike conversions with kits across a range of price points.

• Reduced cost: Purchasing a premium kit costs less than a complete e-Bike

• Flatten hills: Easily make it up steep climbs and arrive at your destination faster and sweat-free

• Customizable options: Beyond being able to ride nearly any bike you want, you can choose the motor type, power, battery size, and more

• Upcycling: Keep your regular bike out of the landfill or cobwebbed corner of the garage and give it new life as an e-Bike!

Many riders are drawn to conversion kits because of the reduced cost compared to a brand-new e-Bike, but it’s not their only option. Upway sources overstock and used e-Bikes so you can get a high-quality ride at a deep discount!

Not all e-Bike conversion kits are created equal— actually, they come in many different designs of widely varying quality. And to make the criteria even more cutthroat, conversion kits that perform well on hills have to be sufficiently powerful and efficient, all without overheating on steep gradients.  

The most talked-about specs when determining an e-Bike’s ability to climb hills are the motor’s power and torque levels. If you’re tackling steep hills, the higher the watts and torque, the better— right? Well, not necessarily. Having sufficient wattage and torque ensures the e-Bike can make it up the climb without stalling, while other important things like ride feel, efficiency, and speed are determined by a combination of factors.

An electric bike motor’s power output is measured in watts, but many experts far from the reach of marketing departments agree that providing a single watts rating is fairly pointless. This is cause for a longer discussion at a later date, but it is essentially because the actual power depends on the combination of motor, controller, battery, and riding conditions— way too many factors to condense into a lone number.

European e-Bike motors are limited to 250W and top models from Bosch, Yamaha, and Shimano can smash steep climes with ease, so don’t feel the pressure to choose a 1000W+ motor just because of its big, marketing-friendly power rating.

How fast can an electric bike go? E-Bikes in the US are limited to a maximum speed of 28 mph with pedal assist and 20 mph in throttle mode. Installing a quicker motor to build a fast electric bike that exceeds those limits could get you in trouble with your local regulations.

Torque ratings, however, offer a more accurate description of an e-Bike’s hill climbing abilities. Torque— the rotating force that drives the motor— is crucial in more demanding riding conditions like moving heavy cargo or climbing a steep hill. High torque ratings allow the electric motor to provide more power and accelerate or climb faster.

When looking for an e-Bike conversion kit, pay attention to the maximum torque rating listed in Newton meters (Nm). You can expect an e-Bike with between 70Nm to 90Nm of torque to have quickness on flat terrain and adequate hill-climbing prowess.

Installing a hub-drive or mid-drive motor are drastically different ways to convert your bicycle into an e-Bike. Hub-drive motors are typically sold as a complete wheel that replaces your existing front or rear wheel, simplifying compatibility worries and the installation process based on wheel size. Front-wheel drive is typically preferred to rear hub motors for compatibility and installation reasons.

Outfitting your bike with a mid-drive motor is a more involved procedure that reaps big rewards when it comes to riding up steep hills. Riders will have to remove and replace the front crankset to install the motor, and it’s exactly that relationship with the gears that give a mid-drive motor an advantage on the climbs.

Shifting gears when pedaling an e-Bike with a mid-drive motor allows you to keep the motor in its most efficient rpm range, offering a huge mechanical advantage. Applying power directly to where you pedal lets the motor combine naturally with the gearing and your own force.

Having a motor in the middle of the bike also preserves better handling, especially on mountain bikes with full suspension and electric mountain bikes. For dedicated trail rippers, check out Upway’s best electric mountain bikes with integrated drive units.

The recommendations on batteries are a bit more straightforward, with higher capacity battery packs providing longer range. Climbing a hill requires more energy than riding on flat ground so skew toward larger-sized batteries if you expect especially hilly rides. The downside to larger batteries is the added weight and bulk on your converted bike.

It’s no secret that conversion kits are more work than simply buying a new e-Bike at your local shop or online. However, the best e-Bike kits make it surprisingly easy to electrify almost any bicycle. Hub-drive kits are less complicated to install compared to mid-drive motors, typically just a swap of wheels, mounting the battery pack, and plugging in the cables.

The major upside of e-Bike conversion kits is that they typically cost significantly less than purchasing a brand-new e-Bike, even an affordable electric bike. Since you already have the rest of the bike, you can spend that extra cash to install a higher-quality motor, controller, and battery. 

I recommend opting for the most premium kit within your budget— upgraded technology like more efficient batteries, UL certifications, and easier maintenance will pay off big in the long run.

Whether or not we like to admit it, how a bike looks matters. Well, at least it matters to me, and I’m not afraid to say it. It’s not the most important deciding factor of an e-Bike conversion kit, but good-looking kits definitely receive extra points.

After all, you don’t want your bike to transform into a Frankenstein-esque mess of bulky batteries, wires, and mismatched parts. Brands like Swytch have paid close attention to the sleek design of their conversion kits, but it’s ultimately up to you to decide which setup you prefer.