Enter the stack height, handlebar width, angle of the stem, and cosine of the stem angle into the calculator to determine the reach of the mountain bike.

Mountain Bike Reach Formula

The following formula is used to calculate the reach of a mountain bike.

R = (S + H) - (A * C)

Variables:

  • R is the reach of the mountain bike (mm)
  • S is the stack height (mm)
  • H is the handlebar width (mm)
  • A is the angle of the stem (degrees)
  • C is the cosine of the stem angle

To calculate the reach of a mountain bike, add the stack height to the handlebar width. Then, multiply the angle of the stem by the cosine of the stem angle. Subtract the result from the sum of the stack height and handlebar width. This will give you the reach of the mountain bike.

What is a Mountain Bike Reach?

Mountain bike reach refers to the horizontal distance from the center of the bottom bracket to the top center of the head tube. It is a crucial measurement in determining the size and fit of a mountain bike. A longer reach can provide more stability and control, especially at high speeds and on steep descents, while a shorter reach can make the bike feel more agile and responsive.

How to Calculate Mountain Bike Reach?

The following steps outline how to calculate the Reach of a Mountain Bike using the given formula:


  1. First, determine the stack height (S) in millimeters (mm).
  2. Next, determine the handlebar width (H) in millimeters (mm).
  3. Next, determine the angle of the stem (A) in degrees.
  4. Next, determine the cosine of the stem angle (C).
  5. Finally, calculate the Reach (R) using the formula R = (S + H) – (A * C).
  6. After inserting the values of S, H, A, and C into the formula, calculate the result.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Stack height (S) = 600 mm

Handlebar width (H) = 700 mm

Angle of the stem (A) = 15 degrees

Cosine of the stem angle (C) = 0.9659