MTB Shock Spring Rate Calculator
Disclaimer:
This Bicycle Spring Rate Calculator is intended as a guideline tool to help riders estimate a suitable coil spring rate for their weight, riding style, and desired sag. Due to the wide variety of suspension designs, leverage ratios, and linkage curves used by different bike manufacturers, results may not be 100% accurate for every frame or shock combination. Get the Most Out of Your Mountain Bike Suspension
For the best ride quality, control, and safety, always confirm your mountain bike suspension setup with real-world sag measurements. Then, review your frame or shock manufacturer’s recommendations. They’ve engineered your bike’s suspension system, tested it in a wide range of conditions, and gathered valuable rider feedback—giving them unmatched insight into the ideal spring rate, air pressure, and shock tuning for your needs. Following their guidance helps ensure your suspension is dialed for maximum performance on any trail.
Why Spring Rate Matters
Your rear shock spring rate determines how much your suspension compresses under load. Too soft, and you’ll blow through travel, bottoming out on jumps or rough terrain. Too stiff, and your bike will feel harsh, with reduced traction and control.
A properly matched spring rate will:
- Give you the correct sag percentage (usually 25–35% for mountain bikes).
- Keep your suspension balanced front to rear.
- Improve grip in corners and on technical climbs.
- Reduce rider fatigue on long descents.
How to Use the Calculator
- Enter your riding weight (including gear).
- Input your bike’s shock stroke and leverage ratio — check your frame or shock manufacturer’s specs.
- Select your desired sag percentage (most riders start with 30%).
- Click calculate to see your recommended coil spring rate in pounds per inch (lb/in) or newtons per millimeter (N/mm).