How to Size an Ebike

As you may have realized, sizing an ebike can be tricky! Everyone’s body is different and making sure you’re getting the right bike for your unique body proportions can seem like one of the most difficult things to do when ordering any bike online. Whether your legs are short and stubby, long and lanky, or somewhere in the middle, the good news is that we are here to help!

We here at Rad Power Bikes get tons of emails and calls from folks needing help picking the right bike for their size, which we appreciate because we want you to get the right bike on the first try. While we focus on our ebikes in this post, the measurement information we provide can apply to pretty much any bike, electric or not! We hope this guide can help you decide which ebike from Rad Power Bikes will be a fit in a way that is more predictable than, but just as satisfying as, Things Fitting Perfectly Into Other Things. We also have videos showing how different riders fit on each of our 2018 models - check them out HERE. 

Sizing an ebike can be intimidating, but you can figure out which bike is best for your body with some basic measurements. Take the time to make sure the bike you want will fit by:

1. Measuring your height and making sure it falls within the recommended rider height range.
2. Measuring your leg length.
3. Calculating your standover height (leg length minus approximately 1 inch).
4. Making sure your standover height is longer than the bike's standover height and your leg length falls between the minimum and maximum seat height.

Take Your Measurements

A good place to start is with yourself, by measuring two of the most important things when sizing an ebike from Rad Power Bikes: your height and your leg length. The video and steps below will walk you through the process.

• Measuring Your Height
  If it has been a while since your height was last measured, it’s better to get it measured by a doctor, or at least a friend with a tape measure, rather than just trusting the digits on your ID card. If you’re getting help from a buddy, stand on a hard, flat surface with your back and heels against a wall; have your friend measure from the ground to the top of your head. Don’t have a friend nearby that you want knowing your actual height? Check out the article linked HERE for strategies to accurately measure your height solo.

• Measuring Your Leg Length and Calculating Your Stand Over Height
  The next, and arguably most important, measurement to assess is your leg length and to determine your standover height. On a bike, the standover height is the distance from the ground to the top of the top tube of the frame just in front of the seat where you will be straddling the bike. Ideally, you want your legs to be long enough so you can straddle your ebike frame with your feet flat on the ground and around an inch of space between the bike frame and the base of your torso. If you need to come to an abrupt stop and quickly dismount from your seat, you want to be able to stand securely flat-footed with an inch or so of daylight between the bike frame and where-the-sun-don’t-shine. Your inseam, which you may know from a pair of good fitting pants, can be an indicator of your standover height. Since your pants don’t typically go to the bottom of your feet and you should be wearing shoes when you ride, it’s likely your standover height will be around an inch or two longer than your pants’ inseam. If the standover height of a bike you want is exactly the measurement of your inseam, you will likely have enough room, but you should measure in the event your pants' size is inaccurate. If you don’t know your inseam or it is a little shorter than the standover height of the bike you’re eyeing, definitely take the time to measure your standover height.

Measure your leg length and standover height by following these steps: 

1. Gather the tools needed: a medium-width hardcover book, a tape measure, a hard and flat floor against a wall you can stand against, and a trusted friend or relative.
2. Stand with your bare feet spread so there is about 7 inches between their inside edge - this is about the distance apart your feet would be when straddling a bike with your feet on the ground (standover height).
3. Place the top or bottom of a hardcover book against the wall with the spine of the book facing upward. Slide the book upwards towards the base of your torso until it is just barely touching your body. This may be a bit awkward, but is way more comfortable than trying to ride a bike that is too big.
4. If you have a buddy helping you, get them to measure from the floor to the top of the book spine while you hold the book in place; if you’re going it alone, carefully hold the book in place and measure from the ground to the top of the book spine.
5. Write down or remember your leg length and calculate your standover height - subtract one inch or so from your leg length.

Compare Your Leg Length to the Minimum and Maximum Seat Heights
Knowing your leg length can not only help you calculate your standover height, but it can also help you determine if you can safely extend your legs to reach the pedals. As like most bike brands, we measure the minimum and maximum seat height from the top of the seat to the top of the pedal in the bottom of the pedal stroke. As long as your legs can reach the pedals, which you’ll know if your leg length falls somewhere between the minimum and maximum seat height, you should be able to find a comfortable riding position. Have long legs? Since our bikes are electric, you don’t need the optimum leg extension to propel the bike forward and it is possible for you to be comfortable while pedaling without getting a full extension.

Use Your Measurements to Size Your New Ebike
Once you know your leg length and your standover height, you can compare that to the standover height and seat height range of all of our ebike models. The standover height and max/min seat heights are located on each bike’s product page. You can also check the Rad Power Bikes Bike Size Comparison Chart here: 

2019 Rad Power Bikes Bike Size Comparison Chart 

2018 Rad Power Bikes Bike Size Comparison Chart 

 As an example, since I have a 31.5” inside leg length, I have a 30.5” standover height, and I can safely stand over every Rad Power Bikes ebike frame except the RadCity 19”. I can also fully extend my legs while seated on every Rad Power Bikes ebike since the max seat height for all the bikes is longer than 31.5”.

Take a Test Ride 
Seeing a bike in person and getting on it will always be the best method for determining whether or not a bike will be comfortable for you. While we do not have dealers or retailers (which is a large part of the reason we can sell such high-quality ebikes at nearly half the cost of comparable models), we do have an expanding network of rental fleet and test ride locations around the country, which you can check out on the page linked HERE. Since there may not be a test ride location near where you are or where you’re planning or willing to travel, you can use the following tips to make sure you’re getting the right bike for your size.

Other Rules of Thumb

• Measure yourself twice or three times to make sure they are accurate.

• If you fall between sizes, go with the smaller size - it will likely have a lower center of gravity and be easier to control.

• Get help from any reputable bike mechanic to adjust the seat height and angle as well as the angle of the handlebars to best fit your body.

• When in doubt, give us a call - we are happy to chat with you about the best options for your body size and how you plan to ride!

Still have questions? Visit our website to learn more about each model, and give us a call Monday-Friday between 9:00 am - 5:00 pm Pacific Time to chat with a Customer Experience Specialist who can assist you in choosing the best bike for you!