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Old 06-09-16, 11:54 PM
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catgita
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You should generally get a similar ride with twice the weight at twice the pressure. But that is on a hard surface. Dirt gives way under higher pressures. You need tires about 50% larger to run the same pressure as someone half your weight, which would give you similar flotation and traction.

A good starting point for your tire pressure would be 75 rear, 65 front. So 80 seems quite reasonable if pinch flats have been an issue. A lighter rider probably will more readily unweight the saddle over sharp bumps, so might get away with proportionally lower pressures.

Your 40mm tires are a good choice for your weight. The load carrying capacity of tires increases exponentially with width, but in a linear fashion with pressure. 50% wider means half the pressure, but the pressure rating would be only a little lower for a similar tire.
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