1. What is the Fox MTB Spring Rate?

The Fox MTB spring rate (K) determines the stiffness of your suspension spring. It's calculated based on rider weight, desired sag percentage, and suspension travel to optimize bike performance and comfort.

2. How Does the Calculator Work?

The calculator uses the Fox MTB spring rate formula:

Where:

• \( K \) — Spring rate (N/mm)
• \( Rider\ Weight \) — Rider's weight in kilograms
• \( Sag \) — Desired sag percentage as decimal (e.g., 30% = 0.3)
• \( Travel \) — Suspension travel in millimeters
• \( 9.81 \) — Acceleration due to gravity (m/s²)

Explanation: The formula calculates the force needed to achieve your desired sag percentage based on your weight and suspension travel.

3. Importance of Correct Spring Rate

Details: Proper spring rate ensures optimal suspension performance, improves traction, maintains pedaling efficiency, and provides a comfortable ride.

4. Using the Calculator

Tips: Enter your weight in kg, desired sag percentage (typically 25-30% for rear, 15-20% for front), and your suspension's travel in mm. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical sag percentage for MTB?
A: For rear suspension, 25-30% is common. For front suspension (fork), 15-20% is typical.

Q2: How does rider weight affect spring rate?
A: Heavier riders need stiffer springs (higher K value) to achieve the same sag percentage as lighter riders.

Q3: What if my calculated spring rate isn't available?
A: Choose the closest available spring rate. It's better to go slightly stiffer than softer if between sizes.

Q4: Does riding style affect spring rate?
A: Yes, aggressive riders may prefer slightly stiffer springs, while trail riders might prefer softer setups.

Q5: Should I use this for both front and rear suspension?
A: Yes, but remember front and rear typically use different sag percentages.