1. What is Scrub Radius?

Scrub radius is the distance between the center of the tire contact patch and the point where the steering axis intersects the ground. It's a critical parameter in vehicle suspension design that affects steering feel, stability, and tire wear.

2. How Does the Calculator Work?

The calculator uses the scrub radius formula:

Where:

• \( Track \) — The distance between the center of two tires on the same axle (mm)
• \( Kingpin \) — The distance from the wheel center to the kingpin axis (mm)

Explanation: The formula calculates the offset between the tire's centerline and the steering axis intersection point with the ground.

3. Importance of Scrub Radius Calculation

Details: Proper scrub radius is essential for vehicle stability, steering feedback, and minimizing tire wear. It affects how the vehicle responds to braking forces and road irregularities.

4. Using the Calculator

Tips: Enter track width and kingpin offset in millimeters. Both values must be positive numbers with track width greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical scrub radius value?
A: Most vehicles have a scrub radius between 0-25 mm. Positive scrub radius is common in front-wheel drive vehicles, while rear-wheel drive vehicles often have negative scrub radius.

Q2: How does scrub radius affect braking?
A: Scrub radius creates a lever arm that affects steering during braking. Too much scrub radius can cause steering pull during braking.

Q3: Can scrub radius be adjusted?
A: Yes, scrub radius can be modified by changing wheel offset, using wheel spacers, or modifying suspension components.

Q4: What are the effects of incorrect scrub radius?
A: Incorrect scrub radius can cause excessive tire wear, poor steering returnability, and unstable braking behavior.

Q5: How does scrub radius relate to kingpin inclination?
A: Kingpin inclination and scrub radius are related parameters that together determine the steering geometry and vehicle handling characteristics.