Originally Posted by
tarwheel
A few words about the Jan Heine study referred to, which concluded that wider tires have lower rolling resistance than narrower tires. The caveat to this statement is "all things else being equal," which they seldom are. Heine's study reached that conclusion for tires that weighed about the same -- that is a 32 mm tire that weighed no more than a 23 or 25, which we all know is hard to find.
it's not just the weight that has to be equal, but also the air pressure inside the tire, and i've never seen any wider tires that can take 130psi like most road bike 23s can take.
now, is 130psi the most practical pressure for city bike commuting, perhaps not depending on a given situation, but i do know that on days when i ride my road bike into work, there's an indescribable joy that only comes from flying across smooth asphalt with a rock hard tire.
but when it's wet out (or wetness threatens) i'm back on my hybrid with 35s @ 85 psi. staying alive is another type of indescribable joy
