Just like a regular bicycle, there’s no “one-size-fits-all” mentality with an electric bike. They come in various sizes, as discussed in our comprehensive electric bike buying guide. There, we outline the various types of bikes and what terrains they’d be best for along with popular options, and even useful accessories to consider. When it comes to sizing, tires are important but there’s a lot more to consider as well.
Frame size
The two most important factors when determining the right frame size for you are your height and inseam measurements between your legs. While you might be able to raise and lower the seat on an electric bike and swap out the tires it comes with for larger, smaller, or even thicker or thinner ones, the frame size is one aspect that remains unchanged. So, you want to make sure it’s the right fit, literally.
To determine the right frame size for your height and what the frame will look like when you straddle an electric bike, stand against a wall and measure the inseam between your legs. You can place a small object there or even use a pencil or piece of tape to mark the spot on the wall. Then, using a measuring tape, measure the distance from that marker to the bottom of the floor. The marker simulates where the top of the seat should be such that you can stand with both feet on the floor when straddling an ebike. To ensure accuracy, wear the same pair of running shoes you’d likely be wearing while riding.
Once you determine the right frame size, there is another slight difference to consider between road ebikes and mountain ebikes. For myself personally, I’m about 5’6’’ but I also have longer legs than the average person. Because of this, with my inseam measurement of 29.5 inches (75 cm), a road bike with a frame size of 54-56 cm (21-22 inches) would be ideal for me versus one that’s a bit shorter at 52-54 cm (20.5-21 inches) that might suit others the same height as me. With a mountain bike, I should opt for a slightly smaller frame size of 43-48 cm (17-19 inches). This is because mountain bike frames are generally smaller to allow for easier handling, particularly on rough terrain.
Here’s a handy sizing chart that outlines the proper sizes based on the rider’s height and inseam. Use this as a general guide in terms of your height, but it’s a good idea to measure your inseam just to be sure.
Saddle height
Next is saddle height, which represents the seat you’ll be sitting down on while riding. These are usually adjustable, and this is something you can tweak after you already own the bike. But how do you know the right height?
Sit down on the bike and make sure that when you place your foot on the bottom pedal, there’s a slight bend in your knee and your leg isn’t straight. As you ride, make sure your knees don’t rise too far above the top tube on the frame of the electric bike. If so, you’ll want to lower the seat a bit more.
Saddle tilt is another thing to look at. If that’s an option, slightly tilt the seat forward for a cruiser or commuter electric bike, and tilt even more forward with an electric mountain bike: this will provide you with the most comfortable seating position for high speeds. With any other type of electric bike, keep the saddle parallel to the ground.
For teenagers, it’s a good idea to check the saddle height every few months to ensure it’s still at the right height and position for their changing bodies.
Tire size
Keep in mind that the size of the tires will reflect upon the overall size of the bike, so if the bike you want comes with bigger tires, or you plan to swap them out, you will have to factor this into your measurements.
The most common wheel size is 26 inches so chances are, most electric bikes will come with wheels of this size. If it’s a folding electric bike, however, you might find that it comes with smaller 20-inch or even 16-inch tires, so double check this before selecting one.
If you are very tall (as in 6’3’’ or taller) you might have to consider looking for an electric bike with larger wheels to ensure the most comfortable seating position and ride without your knees coming too close to or hitting the handlebars. Electric bike wheels come in sizes up to 29 inches.
How you’re sitting
How you sit on a bike comes down to posture. If it’s a commuter or urban bike, you should look like you are sitting in a chair, totally upright, even with the slight tilt of the seat for comfort. If it’s a mountain bike, lean slightly forward to comfortably navigate more difficult terrain and travel at higher speeds.
Weight limits
Most ebikes can accommodate riders as heavy as 300 lbs., but not all of them do. So, if you are in the 200-300-lb. range, double check the weight limit for an electric bike before you choose one.
Even if you are under 200 lbs., if you plan to carry cargo with you while riding, like a heavy backpack with your laptop, a week’s worth of groceries, or heavy items for deliveries, you need to factor that in. Consider the average weight of your typical cargo load (e.g. a 12-lb. laptop plus books, full water bottle, and gear, add that to your weight. If you’re on the heavier side, add about 20 lbs. to your weight and use that as a guide for total carry weight just to be on the safer side.
Pick the right size, adjust to fit, and ride!
Before considering the size of your electric bike, the first thing you need to do is choose the right ebike for you. Once you have narrowed down the type of ebike you’re interested in, you can then look into sizing considerations based on your height, body type, and frame.
It’s about more than just the tires and an adjustable seat, as noted: the frame size is key, as is your body positioning. Once it all comes together, however, you’ll be gliding through the neighbourhood, streets, or up and down local trails and enjoying your brand new toy.
Find a wide selection of electric bikes at Best Buy Online.