How to Size a Mountain Bike Frame
Mountain biking is an exciting sport that can be as extreme or as low key as you want to make it. There are many trails that exist within the limits of major cities and municipalities, yet offer the same challenge and excitement as being in the middle of the wilderness on an uncharted trail. Safety is key in mountain biking, however, as there are unique and unexpected challenges and dangers that come up while trail riding that never come up during a road ride. One important part of mountain biking safety is having a bike that is fitted correctly.
Other People Are Reading
Things You'll Need
- Calculator
- Pencil
- Paper
- Frame sizes for the brand of bike you are looking at
- Tape measure
Instructions
-
-
1
Measure your inseam in centimeters by standing facing a wall barefoot and placing a book vertically between your legs. Make sure the book end is pushed firmly up against your pelvic bone and then step away from the book and place a mark on the wall at the top edge of the book. Measure the distance from the mark to the floor.
-
2
Multiply your inseam by .65 to get a rough idea of your road bike frame size, then subtract 10 centimeters. Convert this measurement to inches by dividing this number by 2.5 to get your mountain bike frame size. For example, if you have an 80 centimeter inseam measurement, your road bike size would be 52 centmeters (.65 x 80) and your mountain bike size would be 16.8 or about 17 inches ((52-10)/2.5).
-
-
3
Consider and compare tube lengths on mountain bikes in your size range. Different top tube lengths and angles make a difference in the way a mountain bike will fit your riding style. Longer top tubes with larger angles will feel a bit "racier" and handle better while climbing and going slow speeds, while shorter tubes and steeper angles will feel more relaxed and descend better. Pick the bike that fits you and will fit your riding style.
-
1
Tips & Warnings
Many shops will custom fit a bicycle for you at no charge if you are buying from them.
If in doubt, go one size smaller than what you calculated as your size. A smaller bike will handle well on trails and is not a danger like a bike that is too large is.
