How to Size a Bike

Once you’ve decided which bicycle type best fits your riding needs, you’ll want to correctly size your bike. If your bike doesn’t fit your body size and riding style, you run the risk of feeling cramped and awkward as you ride. A properly sized bike is also more efficient, helping you get the most out of your pedaling effort. Read on for some important considerations when sizing a bike.


By making sure your frame size fits your body length, you can avoid uncomfortable and overly strenuous bike rides, as well as potential neck and back problems. An undersized frame makes your bike seem cramped and prevents you from fully extending your legs to maximize power, while an oversized frame can make your bike unwieldy and possibly cause injury—especially if you don’t have enough clearance over the frame when standing, straddling the frame. To make sure your frame is the correct size for your body, throw your leg over the bike’s top tube and straddle it with both feet on the ground. If you’re sizing a road bike, touring bike, or hybrid, you should have about an inch of clearance. For mountain bikes, allow two inches or more. You’ll want to wear the shoes you’ll be riding in to get an accurate reading.

If you intend to install a basket, panniers, or a baby seat to your bike, you should check the frame to make sure it can accommodate these attachments.

Seat Height & Position

If your seat height is too low, it can stress your knee and you’ll have less power into the pedals. Your upper legs will tire quickly too. However, if your seat height is too high, it can stress your knees and cause knee pain.

Most recreational riders have their seat positioned too low in a misplaced effort to make it easy for their feet to reach the ground while seated on the bike. The pedals of a bike need to be off the ground by a few inches in order to clear the road surface even when the bike is leaned tightly into a turn. The seat height must be adjusted to give your legs proper extension to the pedals, not to the ground. When you have both feet planted firmly on the ground it’s called walking. Bike riding is about your interaction with the pedals and the bike’s interaction with the ground.

To get the correct seat height, position the seat so that your leg has a slight bend of about 10 to 15 degrees when the pedal is at its lowest point. If your hips rock from side to side while you pedal, it’s a sign that your seat is too high and you are straining to reach the bottom of the pedal stroke.

While some riders position their seats with a slight tilt, most prefer seats that are pretty much level. It’s easier to slide off of a tilted seat. This can cause your arms to tire quickly from the constant push or pull as they try to keep you centered.


Handlebar position plays a crucial role in keeping you comfortable while on your bike. Incorrect handlebar size or adjustment can lead to back pain, shoulder strain, and sore wrists. In general, your arms should be slightly bent so that you feel comfortable while riding. However, handlebars are typically sized to the bike, with different bike styles requiring slightly different handlebar arrangements. Racers and touring bikes usually have handlebars that are the same width as your shoulders, while mountain bikes are even wider.

With regards to handlebar height, road bikes typically have handlebars that are lower than the top of the saddle, while the handlebars on mountain bikes sit even lower, offering the rider a lower center of gravity. Hybrids tend to have handlebars that sit higher than the seat, providing a more comfortable, upright position. If you prefer a more upright position on your own bike, feel free to set the handlebars a bit higher. Depending on your bike, this might require adding a stem riser and lengthening control cables. Just remember, when you do this you’re making your bike less aerodynamic, which for most recreational riders is no big deal. Whatever you do, make sure not to fix your handlebars higher than the minimum insertion mark on older style “quill” stems, and be sure the stem is tightly secured to the fork steer tube, or turning the handlebars will do just that—turn the handlebars, rather than steer the bike.


Wheel size is measured as the diameter and width of the wheel with a tire mounted to it. The size is usually written on the side wall of the tire. In general, larger diameter, more slender tires allow greater speeds; while smaller diameter, thicker, wider tires can withstand larger loads and greater impact. Mountain bike’ wheels are generally 26” (559 mm) or 29” (622 mm), and are usually recorded in inches because of their origin in the United States. Cruisers and some leisure bikes are often 26” as well. Road bikes, touring bikes, and most hybrids tend to have tires designated as 700c (622mm) on rims with a slimmer width (usually 18-25 mm). As you might have noticed “29ers” and road bikes have the same “bead set diameter” of 622 mm, but the larger width tires of the “29ers” end up with an overall diameter that is much larger than a narrower a narrower road tire. Most BMX bikes have 20″ (406 mm) wheels, though some come with 20″ (451 mm) just to keep you guessing.


When selecting pedals for your bicycle, you will have to choose between three basic pedal types—platform pedals, pedals with toe clips, and clipless pedals.

Platform pedals are what most people think of when envisioning bike pedals. The basic platform pedal is broad and flat on both sides, and can accommodate almost any kind of shoe. Some platforms come with notched surfaces to help grip the treads on your shoe. Because platform pedals aren’t attached to your shoes, you don’t have plan ahead when making a fast stop, reaching down to loosen toe clips, or twisting your heels out of clipless pedals. However, for the same reason, you can’t pull up when pedaling, you are limited to just pushing down rather than pedaling in a circle, and it’s easier for your feet to slip off of the pedals when you don’t put effort into keeping them there.

Toe clips are plastic or metal cages that are bolted to platform pedals. They typically feature adjustable, straps to hold your feet in place. Because toe clips keep the balls of your feet centered over and attached to the pedals, you get more power transfer through the entire pedaling circle. This is especially noticeable when climbing steep hills. However, getting into and out of toe clips can be potentially dangerous. In order for the clip to work properly, you must start pedaling to get the bike moving and balanced, then somehow manage to get your toes into the “cages” before you reach down to tighten the straps. And once the straps are tightened, your foot is often stuck. Perhaps the biggest challenge presented by toe clips is trying to slide your feet out of their toe clips before coming to a stop and loosing your balance.

Favored by professionals and enthusiasts, the confusingly named clipless” pedals require special bicycle shoes with cleats that clip into the pedals. Since the cage is what the word “clip” refers to in “toe clips,” the newer fangled “clipless” pedals should have been named “cageless pedals” to save us much confusion—as referring to a pedal system that facilitates your shoes “clipping” into the pedal as “clipless” defies logic. Like toe clips, clipless pedals offer the rider more power transfer when pedaling. However, clipless pedals are designed to release when you pivot your foot to the inside or outside, making it easier to dismount as well as easier to “clip in”. Clipless pedal systems’ cleat design varies from brand to brand, so equipment is not interchangeable. For this reason, it’s important to make sure you purchase the right shoes for the brand of pedal you’re buying. Because clipless pedal systems require specially designed pedals and shoes, they are also more expensive than other pedal types.

Weight. Durability. Cost.

There’s a relationship between weight, durability, and cost that is best described with a chart:

The Perfect Bike
Many would-be riders waste years of their lives searching for this Mythical Perfect Bike, refusing to settle for a nice bike that costs a fair price. Rather than having years of fun and all of its benefits, they continue to wait for that “good deal.”

Riding is already a good deal, and the sooner you start the more chances you’ll have to get a good deal of riding in.

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