Tire pressure has a profound influence on ride quality, performance, and tire longevity. Skinny tire tire pressure is pretty straightforward, easily broken down into a formula. While there will always be a necessity for fine-tuning a few PSI here and there, the basic guidelines are simple.
Jan Heine’s finding that 15% tire drop (the amount of height lost when a tire compresses under load) is the sweet spot between comfort and speed has been accepted and put into practice across the cycling world. More than 15% drop and rolling efficiency is compromised causing a loss of speed. Greater than 15% and the rider’s body is forced to absorb too much “chatter,” which wastes energy. What’s more, Heine found that the 15% drop held true for all road surfaces—from quite rough to freshly smoothed asphalt. This number also works across road-cycling disciplines as well—from touring to racing.
So, is there a one-size-fits-all formula for correct road tire pressure?
Well, kind of, but variables like rider preference and tire construction can affect things a bit. Based on Heine’s chart below, you should experiment with higher or lower pressures than those given. For instance, on rougher roads or if you crave a more forgiving ride, drop a few PSI, which will also enhance traction. If you want to skew the equation to favor speed, and your body can handle the added stress from absorbing the deflection caused by higher pressure, add a few PSI for more efficiency. Keep track of your tire pressures and resulting experiences in a journal, and eventually you will have an answer to the tire pressure question.