The best electric bike conversion kit
Electric bikes are a great way to get out and about, but most are quite expensive. A more affordable alternative is to take your existing bicycle and fit it with an electric bike conversion kit.
Our straightforward guide contains lots of useful information, and we've also made a few recommendations at the end. Our favorite, AW's 26-Inch Electric Bicycle Motor Conversion Kit, combines great quality with high performance. It's also easy to install, so you'll soon be effortlessly zooming along.
Considerations when choosing electric bike conversion kits
Volts and watts
When you're looking at electric bike conversion kits, the headline figures show volts and watts. Volts can be looked at as the force available to propel the bike. More volts generally equals faster acceleration. Watts are best seen as the maximum power available. Although other configurations are available, most of the time you'll see one of these three:
36 volts, 500 watts
48 volts, 750 watts
48 volts, 1,000 watts
There's little point in putting a 48-volt battery on a 500-watt motor -- it's more power than the motor is capable of using efficiently. By the same token, a 36-volt battery has insufficient energy for a 750-watt motor.
The other important factor is the Amp hours (Ah) of the battery (sold separately), which is effectively the fuel level. If you take two 36-volt batteries -- one rated at 10Ah and the other at 16Ah -- the latter delivers consistent output for much longer, giving you greater range.
Although manufacturers often give expected top speeds, several factors other than volts and watts have an impact. Most important are the weight of the bike and rider, and the overall condition of the bike. There's a lot of difference between a well-maintained bike that's moving freely and one with a rusty chain and gears that can sap the motor's energy.
Where to fit your drive
Front wheel electric bike conversion kits are often less expensive, easier to fit, and you retain the bike's existing gearing. On the downside, they add a lot of extra weight to the front of the bike, which affects the feel. There's usually an increase in front-tire wear.
Rear wheel electric bike conversion kits retain a more natural feel, because the drive is coming from the rear, as before. That said, the front can feel light, particularly when accelerating. Fitting is a little more complex, and kits often cost more.
So, which is best? It really depends on whether price is the major factor (choose front drive), or you want to retain as much of your bike's original handling as possible (choose rear).
Those are the main options, though there are others that increase convenience. You might want to think about throttle control (twist grips are easier to control than thumb levers), and useful extras like battery-level indicators or handlebar displays for speed and distance.
Inexpensive e-bike conversion kits can be found for around $160 and are 36-volt, 500-watt models. Most 48-volt, 750-watt or 1,000-watt models cost between $190 and $250, with a few as much as $400. That's still a big savings over buying a complete electric bike but bear in mind, the battery and charger aren't included. They add anywhere from $230 to $400 to the price.
Q. What kind of bike is best to convert?
A. There are no strict rules, but both commuter and mountain bikes are popular because they usually have a strong frame that can handle the extra weight and power. Where a steel frame usually means a less sporty bike, here it can be an advantage.
Q. Is a converted bike street legal?
A. Yes, they are all legal, but precise regulations vary from state to state. If it's classified as an "electric bicycle," you have no problems. If it can exceed 20 mph or generate over 750 watts, some states call it a "motor vehicle" and different rules apply. You need to check local statutes.
Electric bike conversion kits we recommend
Best of the best: AW's 26-Inch Front Wheel Electric Bicycle Motor Conversion Kit
Our take: Powerful pedal-assist model with comprehensive features.
What we like: Impressive performance from 48-volt, 1,000-watt motor. High-quality components are relatively easy to fit. Clear multi-function LCD displays mileage, speed, battery power, etc. Hard-wearing tire included.
What we dislike: A few motor reliability and charging problems.
Best bang for your buck: Voilamart's 26-Inch Rear Wheel Electric Bicycle Conversion Kit
Our take: Affordable high-performance conversion built to European safety standards.
What we like: Rear-wheel drive is preferred by some, and this delivers lots of power. Restricted to 750 watts, so it's road legal. Twist throttle includes battery display. Very competitive price.
What we dislike: Inconsistent quality control, and some problems with support.
Our take: Basic but reliable road legal kit offers excellent value for money.
What we like: Low-cost, easy to assemble, and has everything you need (except the battery). Crank sensor provides feedback for pedal-assist. Twist throttle gives good speed control.
What we dislike: Tire quality could be better. Can struggle on hills.
Bob Beacham is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.
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