SilPSI - SILCA Tire Pressure Calculator

What PSI should I run on a 47mm gravel tire at 65kg?

For a 65kg total system weight on a 47mm measured tubeless gravel tire, the SILCA methodology recommends roughly 30–33 PSI rear and 27–31.5 PSI front, depending on wheel size and surface — moderate gravel runs about 3 PSI lower than hardpack.Inputs held constant across all four rows: 65 kg total system weight (rider + bike + gear) · 47mm measured tire width · high-performance tubeless · 47/53 gravel weight.

What PSI should I run on a 61mm (2.4") MTB tire at 80kg?

For an 80kg total system weight on a 61mm (2.4") measured tubeless MTB tire on rough singletrack, the SILCA methodology recommends 14.5 PSI rear (1.0 BAR) and 13.5 PSI front (0.9 BAR).Inputs: 80 kg total system weight · 61mm measured tire width · 700C/29" wheel · high-performance tubeless · 46.5/53.5 MTB weight distribution · fast singletrack pace · Category 3 (rough) surface condition.Front13.5 PSI0.9 BARRear14.5.

How to Use the Calculator?

1Enter Your Total System WeightAdd up your body weight, bike weight, and any gear you'll be carrying (bottles, bags, tools, etc.). You can enter the weight in either pounds (lbs) or kilograms (kg).2Select Surface ConditionChoose the type of terrain you'll be riding on, from smooth indoor tracks to rough gravel roads.