Originally Posted by Helmet Head
Well, maybe the RR is not that big a difference, but the weight difference certainly must be. Why turn all that extra weight? Why carry that extra weight up hills? As far as comfort and flat resistance... again, 700x23s are comfortable on centuries (and I know many people who use them on double centuries and beyond), so I don't understand the comfort issue. As far as flat resistance, I haven't gotten any flats on my 700x23s in 2 years and several thousand miles of commuting and recreational rides.
Unless one lives somewhere with no hills and lots of cobble-stoned streets, I don't understand the point of carrying the extra weight of anything heavier than a 700x23.
As far as weight, I just checked. My GP4 seasons weigh the same in 700x28 and 700x23 trim. A check of the specialized site shows that, for most tires, the diff between 700x23 and 700x28 is less than 20 grams. Even the armadillos are only about 60 grams more.
Besides, if rotating mass is your thing, swap your wheels for 650As or even 559s.
Even on "great" pavement, I find the 28s much more comfortable. On the pavement around here...well...it's like night and day. My entire commute is worse than anything I used to ride in Silicon Valley, and some is so vastly worse that you'd have to see it to believe it. Flat resistance is a very big deal.
And anyway, it's just nuts to quibble over 20 or 60 or 100 grams of weight when I'm carrying 10+ lbs of stuff.