Have your assistant measure the same points as before for both front and rear wheels. Finally, for each wheel, divide the second measurement by the first measurement and multiply by 100. If both the front and rear are 85 or greater, you have sufficient pressure for efficient cycling. If not, adjust your pressure accordingly and be careful not to exceed your tire maximum.
Tire compression or "drop" while under load.
Weight of Cyclist
Heavier riders require higher pressures in the same size tire. For example, junior cyclists that weigh less than 100 pounds do well with no more than 80 pounds of pressure in both tires. Higher pressures for lightweight riders provide little benefit in rolling resistance while decreasing tire adhesion with the road surface. This can lead to energy-sapping frame vibration and cause poor cornering and handling on rough roads.
Any detailed discussion of tire pressure should also take into consideration the quality and type of tire being used. A quality clincher with a higher thread count in the sidewall will result in a smoother ride at higher pressures. Sew-ups or "tubulars" tend to provide a smoother ride at similar pressures.
Regardless of tire type used, be careful not to over pressure your tires. Too many times, I have seen riders experience catastrophic tire failure at a race because of over-inflated tires...apparently trying to gain that last bit of performance with the highest pressure.
Over-inflated tires fail dramatically and often sound like a gunshot! A lower pressure will provide a smoother ride, better tire adhesion on the road and better control.
I think we all dream of that mystical ride along a beautiful winding country road paved with new asphalt. Reality dictates that much of your riding will be on a variety of surfaces. Generally speaking, most riders use a slightly lower pressure on rough roads.
With lower pressures, the tire deforms to the uneven surface and makes better contact with the road. This reduces vibration and provides better traction and control. A smooth surface, such as new pavement, will allow higher tire pressures and provide a fast and pleasant ride. Dirt or gravel roads dictate lower pressures on wider tires. Racers in the famed Paris Roubaix, for example, choose wider tires to accommodate both rough cobblestones and smooth pavement. Racers have been rumored to run 28-millimeter wide tires with as little as 50 pounds of pressure.
Lastly, check your tire pressure regularly. You can do this by attaching your pump and checking the gauge without applying a pump stroke. Better yet, purchase a stand-alone pressure gauge from your local bike shop. Either way, paying closer attention to your tire pressure for the conditions at hand will lead to a more efficient and satisfying ride.Search for a cycling event
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