Learn Center:. What should my tire Pressure Be? Many newcomers to cycling don't think about inflating their bike tires to the proper pressure. Tire inflation basics. Hitting the PSI sweet spot. Expert Advice. We love talking to our customers and sharing our gear knowledge. Our Customer Service team is based in Utah and knows our products inside and out. We're here to answer any questions and match you up to the right gear and the latest deals.
Alternatively, there are generally-accepted ranges based on bike type:. Road bikes and tires are built for speed over smooth surfaces. Higher air pressure lets them roll easier and faster.
A typical range for these would be between 80 and psi, although racers can sometimes go as high as psi. Quick tip if you're caught inflating a road tire without a gauge and need to ballpark it: at psi, a tire can barely be compressed with your thumb. Unlike roadies, mountain bikes are flying over loose, bumpy terrain. Tires with too much air lead to too much bounce, making for a jolty ride. Lower pressure helps with shock absorption while also giving you more traction since more of the tire comes into contact with the ground.
MTB manufacturers recommend between 30 and 50 psi on most of their bikes since this is a nice balance between on-road closer to 50 and off-road closer to 30 riding.
Hybrid bike tires require pressure levels between those of road and mountain bikes. This is usually in the 50 to 70 psi range. Kids' bikes have the lowest recommended inflation, typically 20 to 40 psi. Keep in mind that these are called "recommendations" for a reason, though. A number of factors go into the inflation process beyond just your style of bike.
Because nothing in life is ever as simple as it should be, we've included a few more things to ponder when it comes to making sure everyone's tires are in good shape for their next ride. Whether you're competing in the Tour de Whatever or shredding up the backcountry, heavier riders should use a higher psi than lighter ones to see the same performance in their tires.
For perspective, someone weighing in at lbs will probably want to pump in around 20 more psi than someone who's The opposite is also true.
However, on imperfect surfaces, like roads, very high pressures simply increase vibrations and can slow you down. When roads get very rough, smaller tyres anything 25mm or smaller running at a relatively low pressure may not be able to provide enough protection for the rim or inner tube — especially for heavier riders — which can lead to pinch flats or even rim damage. Switching to larger tyres will give you a greater amount of tyre volume to play with, so you can fine-tune the pressure to account for both rolling resistance and comfort on rough roads.
This helps increase the amount of rubber in contact with the road, which should improve grip. Doing so could lead to dangerously high pressures building up inside the inner tubes or tubeless tyres, if too much excess heat is introduced to the system.
The materials and construction methods a road bike tyre manufacturer uses can also affect the optimum pressure, to a small degree. Road bike tyres designed for racing or summer use tend to have casings that use a higher number of thinner nylon or cotton threads this is what the Threads Per Inch or TPI number of a tyre refers to , and only a thin layer of rubber tread on top.
This makes them easier to deform under pressure, making for a smoother and faster ride. Conversely, winter road bike tyres typically have stiffer, more durable casings with fewer, thicker nylon threads. The rubber tread on top also tends to be thicker for improved mileage and puncture protection.
Given this, you may need to drop your road bike tyre pressure slightly when moving across to winter tyres because the optimum pressure for comfort and grip is likely to be a few psi lower. So, you have all the information at your fingertips, but how do you actually go about fine-tuning tyre pressure?
The simple answer is experimentation. Start with the recommendations above and then consider what the road conditions are like where you ride. Do you have miles and miles of freshly laid tarmac? If so, the above recommendations are probably close to optimal.
Start with small steps in pressure of around 5psi, and, if you pay attention, you should eventually be able to determine a sweet spot for speed and comfort. So, it turns into a vicious cycle. As soon as your tubeless tires get low enough, every hit will reduce the pressure until you are just riding on your rims. That will destroy your tires in no time. The pressure in your tire changes two main factors, the shape of the contact patch area, and how the tire absorbs impacts from the road surface and debris.
The contact patch is the part of the tire that is actually touching the ground. Higher pressure results in a tire that is much more firm and less of the tire is actually touching the ground.
When you reduce your tire pressure, it is softer and the tire spreads out. For a small contact patch, the tire has less rolling friction. A larger contact patch deforms more of the tire while you are rolling. A larger contact patch will increase the static friction between your tires and the road.
Pressure also affects the kinds and amounts of impacts that your tire is able to handle. If your pressure is too high, your tire will bounce while you are riding instead of staying in contact with the road. A lower pressure will be able to absorb some impacts and smooth out your ride, but hitting something too hard may cause your rim to slice through a tube or tire. They say that amount of sag will maximize the shock absorbing capabilities of the tire, and it will minimize the rolling resistance.
Thankfully, said scientists also made a very nice graph for us.
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