Singlespeed & Fixed Gear - Is there less rolling resistance with 700x23 tires...

as opposed to 700x20. A friend and I are planning on entering a race in a couple of weeks here in Richmond VA.

I just bought a new set of rubinos for use while riding in the city. I told my friend that I would just put the 700x20's back on come race day. He then told me not to b/c even though they are lighter they create more rolling resistance.

Is this true?

(the search yielded no information)

Sheldon Brown has a good article on the subject, http://sheldonbrown.com/tires.html

Its a bit academic. At identical tire pressures then yes, he's right but the thing is you shouldn't run the same air pressure in different size tires. He's right though in saying there's no performance LOSS from running the larger tires and there's the added benifit of a better ride which can stop you from getting bumped off course.

Regards, Anthony

Unless you're an elite level racer you will not experience any performance gain or loss when using 20mm tires rather than 23mm.

i'm inclined to agree with $0.00/Gal, though it's more a gut reaction that any real knowledge. i doubt you'd notice any difference.

excellent...that's good to know. at the very least it saves me some work come race day

I find this interesting.

I presently ride on Conti GP 4 Season 23mm tires.
I plan to try the new GP 4000's, as they weigh less and allegedly have less rolling resistance.
The GP 4000's come in 23mm and 25mm.
I would normally stick with 23mm, but I notice the 25mm tires come with a reflective sidewall and, since I ride quite a bit at night, the reflective sidewall sounds like a good idea.

Conti lists the max pressure for both width tires as 120lbs, but recommends 95lbs for the 25mm tires and 110lbs for the 23mm tires.
Sheldon says the wider of two tires, at the same pressure, has less rolling resistance.
This raises a whole slew of questions.

Has anyone here ridden the same family of tires in both 23mm and 25mm, and what if any differences did they experience?

Wider tires have less rolling resistance because of the way the contact patch is spread out. At least that's what I repeat from this article I read last year on cyclingnews.com.

'fat tyres have lower rolling resistance' (http://www.cyclingnews.com/tech/?id=2005/features/conti_tech)

The charts are interesting but the information about the rolling resistance is toward the bottom.

C'mon, guys.

We're talking about 3 millimeters here. It's not gonna matter.