700/38 vs 700/23 tyres on a "comfort" hybrid commuter bike.
On 2011-11-09, Theo Bekkers (aka Bruce)
was almost, but not quite, entirely unlike tea:
We've had this discussion before and there's no argument that the
rolling resistance of a wide tire and a narrow tire are the same when
both are at the same pressure. However, the narrow tire will
invariably have a higher recommended tire pressure, so when a wide and
Not quite invariably. I upgraded one of my early bikes by replacing
the stock 45PSI tyres with 80PSI ones. Same dimensions, but heck of a
lot better to ride on! Stupid kmart bikes --- BTH bait.
a narrow tire are inflated to their recommended pressures, the narrow
tire will have a smaller contact patch and a lower rolling resistance.
The argument that a wide and a narrow tire have the same rolling
resistance is therefore spurious.
And for the wider tyre, pumped to the same pressure, because there is
a larger radius, it will take a lower deflection before the wider tyre
ends up with a wider contact patch. I am skeptical that this will
lead to a lower resistance.
--
TimC
I've told them and told them: Temporal anomalies are different from
spatial anomalies. But the kittens know better. They laugh at my
feeble attempts to fool them. -- barbara in ARK
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