cycleprincess

Just Saturday I swapped out my 32's (on my Bianchi Volpe) for a pair of 23 Specialized Armidillo's. I thought I'd have to go with 25's or 28's, but at the bike shop they said I could go as small as 23's, so I went for it!! With all the talk of rolling resistance, I figured I'd be better off with a skinnier tire. I was hoping I could gain a little speed with them but so far I haven't noticed a difference. Granted I've only had her out 12 miles on the new tires. How long do you think it'll be before I notice a diffenence in my speed?

AndrewP

Thinner tires have more rolling resistance when inflated to the same pressure, so you will have to put in much more pressure to get any more speed. Reduced weight on the rims should give you better acceleration. The Armidillos are heavy tires - were the 32's also Armidillos. If they werent you may not have any weight reduction, but you will have better flat protection.

cycleprincess

My other tires were not Armidillos. But I ran them at 80 psi, the 23's say I can go as high as 110. So I'm at 110 now with the 23's but the only difference I've noticed so far is a stiffer ride. I feel the bumps a lot more with them, but I was hoping for more speed.

telenick

Princess, you won't really notice much speed difference as much as you'll notice the cummulative effect (over many miles of extreme heat and sweating profusely in the HTH) of less energy output for the same speed.

In order to actually notice a speed difference, you're going to have to increase your cadence and/or change to a faster gear and keep your cadence the same. Cadence and wattage output patterns are things we tend to anchor to over time and they're harder to change than a tire. Many riders will get stuck in similar riding patterns like cadence and speed. It takes a very concerted effort to break long held patterns like that.

I remember you saying that you take spin classes. Do you do very strenuous intervals in spin class? If so, take them to the street and break your riding patterns. Spin a faster cadence, choose a harder gear and try to match it with a high cadence, mix it up. Then you'll get faster with less effort on your 23s.

froze

Princess, the 23's do have slightly less rolling resistence then the 25 and they weigh less. But the advantage to the 25 is on the road where ruts, grooves, pavement edges etc can make a 23 follow those things which could cause some interesting handling situations, whereas the 25 would mostly just roll over that stuff.

If the ride is too harsh for you, you may want to try dropping the air pressure a tad. I weigh 163 and I only put 95 in the rear and 85 on the front (these are 25's, when I ran 23's I ran 10psi more); and been doing this with Armadillos for 3 years with no probs. If you weigh less then I then you could even go less; but experiment to find the perfect pressure for you. If you put max pressure in your tires and don't weigh a lot you could also find the tires skipping over rough services.

Keep in mind these tires are not racing tires, they are a superb commuting/training tire if flats are an issue. One thing you can do to keep the overall weight down as much as possible is to use ultralight 65 to 70grm tubes. But if you decide to race your going to want to use lighter tires for the race.