Tire Pressure Calculator 3.0
Tires are suspension. To enjoy the same ride and feel, a heavy rider/bike benefits from a wider tire than a lighter rider/bike.
Instead of starting with a tire size, tell us how you ride. Based on your input, we'll recommend a Rene Herse tire for your weight and riding style, then calculate your recommended pressure.
Caution!
- Never exceed the maximum pressures of tires or rims (whichever is lowest).
- Your pump gauge may not be accurate. When in doubt, use a tire pressure that feels right and is safe.
- Our pressure recommendations optimize your bike for speed, but speed isn’t everything. Experiment to figure out what works best and is safe for your riding style and terrain.
- Recommendations provided may not be suitable for your equipment and riding conditions.
- Improper inflation can result in equipment damage and/or injury.
Background
More than 20 years ago, the wide-tire revolution was kicked off when our real-world tests showed that high pressure isn’t needed to roll fast. Since then, we’ve run hundreds of tire tests. Together with the engineering department at Cal Poly Pomona, we’ve studied how different weights affect tire deformation. Our pressure recommendations are based on actual performance data—how to make your bike faster.
Working with racers and riders—Gravel National Champion Brennan Wertz, Silk Road Mountain Race winner Meaghan Hackinen and many others— we’ve tested the Rene Herse × Cal Poly Pomona Tire Pressure Calculator 3.0 to make sure it works in the real world. Read more…
Balancing Tire Flex and Vibrations
High pressure makes your tires harder. That reduces flex in the tire (saving energy), and we used to think that made tires fast.
However, high pressure also increases vibrations (that slow the bike down). Today we know that tires roll fastest at a pressure that balances tire flex and vibrations.
This discovery is behind the ‘All-Road Bike Revolution’ and the trend toward wider tires.
Firm or Soft Feel?
On smooth roads, there are two distinct tire pressures that roll fastest:
- Firm: Slightly higher pressure optimizes tire flex.
- Soft: Lower pressure optimizes vibrations.
- Choose ‘Soft’ for more comfort; ‘Firm’ for less tire flex during high-speed cornering.
On rough surfaces, vibrations dominate, and ‘Soft’ pressure rolls fastest and grips best.
Benefits Beyond Speed
A relatively low tire pressure isn’t just fastest. It has other benefits, too:
- Grip: A larger contact patch puts more rubber on the road. Plus: a softer tire doesn’t skip over small bumps, but maintains traction at all times.
- Comfort: Less vibrations = less discomfort
- Fewer flats: A softer tire often rolls over debris that would puncture a harder tire.
