Ohlins Spring Rate Calculator
Optimizing Your Motorcycle Suspension
Choosing the correct spring rate is the single most important step in setting up your motorcycle's suspension. Ohlins springs are engineered to precise tolerances, but their performance depends entirely on matching the spring stiffness to the total load (rider + bike) and the intended application.
Why Spring Rate Matters
If your spring rate is too soft, the suspension will ride too low in its stroke, causing harshness as it hits the "bump stop" and making the bike feel heavy or sluggish. If the spring is too stiff, you won't achieve the proper Rider Sag, leading to a loss of traction and a bouncy, uncontrolled ride.
Understanding N/mm vs. Lbs/in
Most Ohlins components use the metric measurement N/mm (Newtons per millimeter). This represents the amount of force required to compress the spring by one millimeter. To convert N/mm to Lbs/in, you multiply the metric value by 5.71. For example, a 10.0 N/mm spring is approximately 57 lbs/in.
Riding Styles and Tuning
- Street: Focuses on comfort and compliance over potholes while maintaining stability.
- Sport: A balance between chassis control for hard braking/acceleration and road feedback.
- Track: High spring rates to handle the extreme forces of high-speed cornering and aggressive braking.
Typical Ranges
For most modern sportbikes, front fork springs typically range between 8.5 N/mm and 11.0 N/mm. Rear shock springs vary significantly based on the linkage ratio of the bike but often fall between 80 N/mm and 110 N/mm for standard street configurations.