Under Pressure!: How to Choose Tubeless Tire Pressure

Picking the right tire pressure for your tubeless setup is crucial for optimizing performance, comfort, and safety. Whether you’re riding on the road, tackling cyclocross courses, shredding mountain trails, exploring gravel paths, or cruising on fat bikes, the right pressure can make a significant difference. This guide will help you determine the ideal tubeless tire pressure for different types of riding.

For road bikes,  tubeless tire pressure is all about finding the right balance between speed and comfort. Higher pressures reduce rolling resistance but can result in a harsher ride and less grip, especially on rough or wet roads. Lower pressures improve comfort and grip but can increase rolling resistance slightly.

1. Rider Weight: Heavier riders may need slightly higher pressure to avoid tire squirm and maintain performance.
2. Road Conditions: On smooth roads, higher pressure is ideal. For rougher roads or wet conditions, lowering the pressure can improve grip and comfort.

Example: If you weigh around 160 pounds (72.5 kg) and ride on a mix of smooth and rough roads, a pressure of 85 PSI (5.9 bar) in a 28mm tire might offer a good balance between speed and comfort.

Cyclocross courses often feature a mix of grass, mud, sand, and pavement, requiring a tubeless tire pressure that maximizes grip and control without sacrificing speed.

1. Course Conditions: For muddy or loose surfaces, lower pressure increases the tire's contact patch, improving traction. On harder surfaces, slightly higher pressure can enhance speed.

2. Rider Weight: Lighter riders can run lower pressures without risking tire burping or rim damage, while heavier riders may need to increase pressure slightly.

Example: On a muddy cyclocross course, a pressure of 30 PSI (2.1 bar) might provide optimal grip and control for a rider weighing 150 pounds (68 kg).

Mountain biking demands a tire pressure that can handle a variety of terrains, from smooth singletrack to rocky descents. Lower pressure improves traction and comfort, while higher pressure reduces the risk of pinch flats but may decrease grip.

1. Terrain: For rocky or rooty trails, lower pressure helps the tire conform to the terrain, enhancing grip. On smoother trails, higher pressure can improve speed and efficiency.

2. Tire Width: Wider tires (2.4” and above) can be run at lower pressures without risking tire squirm.

Example: For a 2.4” tire on a rocky trail, a pressure of 22 PSI (1.5 bar) might offer the best balance of grip and protection against pinch flats for a rider weighing 170 pounds (77 kg).

Gravel riding involves a mix of pavement, dirt, and gravel roads, requiring a tire pressure that can handle varied surfaces efficiently. Lower pressure improves comfort and traction on loose surfaces, while higher pressure is better for smooth sections.

1. Terrain: On rough gravel roads, lower pressure improves comfort and grip. For more road-focused rides, higher pressure enhances speed.
2. Tire Width: Wider gravel tires (40mm and above) can be run at lower pressures for better comfort and traction.

Example: If you’re riding a 40mm gravel tire on a mix of pavement and gravel, 40 PSI (2.8 bar) might provide a good balance between comfort and rolling resistance.

Fat bikes are designed for extreme conditions like snow, sand, and loose terrain, where low tire pressure is essential for maximizing flotation and traction.

1. Surface: On snow or sand, extremely low pressure (5-8 PSI) helps the tire float over the surface without sinking. For harder packed trails, slightly higher pressure can improve rolling efficiency.
2. Tire Width: Fat bike tires (4” and above) are designed to operate at very low pressures without risking tire burping or rim damage.

Example: For a 4.8” fat bike tire on soft snow, running at 6 PSI (0.4 bar) could provide the necessary flotation and grip for a rider weighing 180 pounds (82 kg).