Tires are perhaps the most important component on your bike. As the only thing keeping you in contact with the ground, and thus in control of your destiny, tires must be properly chosen. Selection is based on riding style and trail characteristics, in this case cross-country (XC), which puts pedaling speed as the most important attribute of a tire.
Generally, XC racers prize rapid acceleration and low rolling resistance above all else. Cross-country tracks usually don’t require the technical bike handling skills, or present the amount of rugged terrain that downhill or enduro racing does. As a result, XC tires tend toward lower tread, narrower footprints, and thinner casings. These days the sweet spot for XC tire width is 2.1 to 2.3.
Firm dirt calls for short, or at least ramped, knobs. This minimizes rolling resistance, and reduces squirming, as taller knobs won’t be able to dig into the hard earth.
Soft or loamy dirt provides a lot of leeway. You can go with a more aggressive design as bigger knobs will dig in—unlike on hardpack where they squirm—and carve through turns with supreme confidence.
Very often, XC mud tires are simply a lightweight version of a moderately aggressive trail/all-mountain tire; choose narrow widths and thin sidewalls. Widely-spaced tread patterns will release wet mud easier, but if you’re riding in sticky clay dirt, most tires will pack up and become unrideable.
Front |
Rear |
Hardpack/Racing |
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Soft/Loam |
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Wet/Mud |
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