Is 350 Watts Enough for an Electric Bike Motor?

Jupiter Bike Discovery X5
Jupiter Bike Discovery X5 with 350-watt motor

Since, I’ve been reviewing mini electric folding bikes lately, I’ve been experiencing 350 watt motors. Actually, my first ebike had a 350-watt motor. Are they enough? It depends greatly upon rider weight and whether you’ll be climbing a lot of hills. In my experience, 350 watts is perfectly fine on flat ground, can hand hills if you pedal along, and have some nice benefits including a quieter motor, lighter weight, and a cheaper price tag.

Wattage ratings on electric motors indicate how many watts the motor can use. They will usually be paired with a 36 volt battery.

A 36 volt 10 Ah battery equals 360 watt hours. If you want to know the watt hours for any bike battery just multiply the volts times the amp hours. So, in this case a 360 WH battery will power a 350-watt motor for 1 hour.

It’s important to note that when you are riding an ebike, the motor will likely not need to draw full wattage. For example, if you’re pedaling along a flat road with good tire pressure and light winds won’t need the full power to maintain a certain speed.

Now if you’re pedaling up a killer hill you likely will be using the full capabilities of the bike motor.

In regard to speed, I could easily hit 20 mph with my first ebike equipped with a 350-watt hub motor. I actually increased the speed through the bike’s display at got up to 22-23 mph. Now the bike wouldn’t be able to maintain that speed for long time periods, but the motor certainly had enough power to get up to that speed.

If you’re of average weight, about 150 lbs, a 350 watt motor will have enough power for flat roads with a few moderate hills tossed in. You may have to pedal with the motor to get up some hills, but the beauty of an electric bike is that they assist you in such tasks. You can still get a nice workout without killing yourself or arriving to work drenched in sweat.

If you’re just using the throttle, if the bike is equipped with one, 350 watts probably won’t be enough to pull you up a hill, and if it does you run the risk of overheating the motor.

Something else that is important to know is that one ebike company advertising a motor as 350 watts may not have the same performance as a 350 watt motor from another company. That’s because wattage can be listed as either nominal capacity or peak capacity. Some companies will list both.

Nominal refers to the wattage at which the motor can work consistently without overheating. Peak capacity is the wattage the motor is fully capable of, at least for short bursts.

Another difference is how the bike is set up. The amount of amps the motor can use is controlled by the bike’s controller.

A 15 amp controller will limit amps to 15. A 25 amp controller will limit to 25. You’ll obviously get more power from a higher amperage controller.

Many ebikes sold in Europe are using controllers to limit the power of the motor due to legal regulations. The controller might be 15 amps. The same bike sold in the United States may be equipped with a 25 amp controller, but the motor might be the same.

There’s also a difference in performance between hub and mid-drive electric motors. A 350-watt hub motor does not equal a 350-watt mid-drive motor. Mid-drive motors are more efficient, typically have more torque as compared to a hub motor, and can utilize the bike’s gears. Mid-drive motors are great hill climbers because of this.

Mid-drive motor on the Liv Amiti E+4

A 350-watt mid-drive motor will outperform a 350-watt hub drive motor on hills.

There are significant advantages to a 350-watt, 36 volt ebike. One that you probably have noticed is that they are more affordable. You’ll also find them on more portable bikes, like the Jupiter Bike Discovery X5 or the Swagtron EB7 Plus.

A 350 watt motor is lighter than a 500+ watt motor. So, if portability is what you’re looking for than 350 watts is a good size. There are some that are as small as 250 watts like the Macwheel LNE-16. It’s actually a very peppy little bike for what it is. It’s surprisingly decent on hills. I suspect its peak power is significantly more than 250 watts.

Another advantage is that smaller motors are typically quieter. If you want to ride along a bike path and not pass by pedestrians or other cyclists without drawing attention to yourself with a loud motor, 350 watts is a good choice. More powerful motors can be quiet too, but vary by manufacturer. Some use better sound proofing materials than others.

So to answer whether 350 watts is enough it depends upon rider weight and hills. If you’re a heavier rider than I’d recommend 500+ watts nominal with a motor capable of higher peak wattage for hills.

If you’re going to be commuting in the city on paved streets with few hills, and you are of average weight 350 watts will be plenty, especially if you enjoy pedaling along for exercise.