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Old 10-12-14 | 03:16 AM
  #19  
Jaywalk3r
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Bikes: 29er commuter/tourer, 26er commuter/tourer, folding mixed-mode commuter

Originally Posted by PaulRivers
I'm going to have to disagree with you that there's any real world situation where new pavement is anywhere near rough enough to need a tire bigger than 23-28c.
It would be rare in the real world for any commuter bike to need a tire narrower than 32-38 mm, unless the frame simply won't fit sensibly sized tires, and such frames really aren't well suited for commuting for that very reason. There's a reason that commuters don't ride skinny tires in places where most people ride bikes for transportation at least some of the time (something that doesn't happen in even the most bike friendly cities of the US).

Even if we accept your dubious claim about all new pavement for the sake of argument*, few of us have the luxury of riding on only new pavement. On typical pavement, in typical cities, 28 mm tires are a poor choice, for speed or comfort. On my commute, I'd have to slow down for a few long stretches to ride on 28 mm tires without flatting them at least twice each week, which would eliminate any slight speed advantage you claim skinny tires provide. With my 40 mm tires, I can go full speed ahead, but it's still pretty rough. Even wider tires, at lower pressures, are faster through those sections. Even where the pavement is in much better shape, it isn't so good that high pressure tires would provide a benefit with respect to rolling resistance. Judging by the condition of many of the streets of the cities through which I rode on my bicycle tour this summer, my streets are at least as good as typical. I will concede that I didn't ride through Minneapolis, so I have no idea what your roads are like.

For road racing, the appeal of skinny tires in their reduced air resistance, since air resistance increases with the square of velocity. That's more important to them than rolling resistance, since that only increases with velocity.

*One of the things I noticed in Florida, as an example, was that even the brand new asphalt had mini waves, reminding me of a Ruffles potato chip. Their high infrastructure design with respect to bicycles, is admirable, but the pavement quality is pathetic, considering how new it was. It probably isn't noticeable to motorists, with their lower pressure tires, though.

Originally Posted by PaulRivers
I don't think your 32c vs 35 example makes sense …
The example is accurate. It's just physics.

Last edited by Jaywalk3r; 10-12-14 at 03:19 AM.
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