How to self-fit your bike
This entry was posted on May 17, 2013.
Having a properly-fitted bike is an extremely important part of good riding. Not only can a poor fit inhibit your performance and make a ride really uncomfortable, it can even lead to injuries. A well-fitted bike has none of these problems and should provide a comfortable, high-performance ride while minimizing aches, pains, and the chance of injury.
The most important part of a proper fit is comfort. A bike that isn’t comfortable won’t make you want to go for a ride, whether for training, touring, or commuting.
This tutorial will explain the basics of proper bike fitting. Remember that these instructions are simply guidelines. Some people will prefer a different fit, and it is always good to try several different body positions to see which one suits you the best. If you have any health problems, especially with your back, consult a doctor or professional before purchasing a bike.
Time required: 20 minutes
- Size 5 and 6 Allen wrenches (Hex Wrenches)
- Indoor trainer (to hold your bike up)
- String or plumb line
Step 1: The first step in fitting a bike properly is to make sure you have the proper frame size. This is usually determined by the standover height. Mount your bicycle, but do not sit on the saddle. Stand upright, and pull the frame up against your crotch. The distance between the wheels and the ground should measure about 1 inch on a road bike or 2-3 inches on a mountain bike. Get a larger or smaller frame size as needed.
Step 2: The next step, if you plan on using clipless shoes, is to set your cleats up properly. When your cleats are aligned, you will be able to adjust the rest of the bike in relation to your exact riding position.
Learn how to set up your cleats with our cleat installation tutorial.
Step 3: Next, adjust the saddle height. To calculate this, mount the bicycle in a normal riding position, and adjust the crackarms until they are vertical. With the bottom foot held in a normal riding position (don’t point your toe or drop your heel), that leg should have a 10-20% bend in the knee. You don’t want your knee locked, and you don’t want it bent more than slightly. Use an Allen Wrench or the quick release on your seat tube to adjust your saddle height to suit.
Step 4: Now, let’s adjust the fore-aft positioning of the saddle. Mount your bike again, and move the crankarms into a horizontal position. Using a plumb line or a string with a weight tied to the end of it, drop a line from the bottom of the kneecap of the front leg. The line should fall directly across the middle of the pedal axle. If the plumb line falls to the rear of the pedal axle, move your saddle forward; if it falls in front of the pedal axle, adjust your saddle to the rear.
Step 5: The next step is to adjust the forward-backward body position. To do this, we will use a method of sighting toward the front hub. Mount your bike, sit on the saddle, and put your hands on top of brake hoods. In a normal, comfortable riding position, sight down towards the front wheel. The handlebar should obscure the front hub. If the hub is visible behind the handlebar, you may need a shorter stem; if it is visible in front of the handlebar, a slightly longer stem will be more comfortable. This positioning should put your back at a roughly 45 degree angle. Racers may like a more tucked position, while touring cyclists and casual riders usually want a more upright position for comfort.
Step 6: Another consideration is handlebar width. In general, handlebars should be about as wide as your shoulders. Women will usually be more comfortable with narrower handlebars.
Step 7: The crankset is another component that requires proper fitting. In general, shorter people will want shorter crankarms. They come in lengths from 165mm to 175mm. Try a few different sizes if you are unsure which to choose.
Step 8: The final adjustment to make is the angle of the saddle. It is best to start with your saddle perfectly level, try a test ride or three, then adjust from there if you like.
Step 9: Now that your bike is fitted to your body, take it for a test ride! You will likely need to fine tune some parts of the fit, but before long your bike should be dialed in to your body and ready to hit the road.