23 or 25s for Tyres.

meanredspider

I swapped backwards and forwards between 23c and 25c versions of the same tyre on my 30-mile RT commute. Then it occurred to me to look to see if there was a difference in speed. Now I'm not going to claim that this is a bullet-proof study but for me (at 85+kg) on Highland roads in the summer, the average speed of a typical 18mph commute was about 0.5mph faster with the wider tyre. Not a lot but 0.5mph is hard to come by. Anyhow, it's convinced me to stick with 25c (certainly no slower)

The funny thing is I dropped into a shop in NL asking for a replacement 25c tyre - the guy looked at me like I was a lunatic saying that no-one uses 25c only 23c...

Bar Shaker

Ai_1 wrote:

Bar Shaker wrote:

jordan_217 wrote:

Mr Evil wrote:

25mm tyres are faster more comfortable, less likely to puncure, have better traction, and last longer. Given all the advantages, I wouldn't buy a frame that doesn't have at least clearance for 25mm tyres.

Really? I use both, same tyre/tubes just different width. Can't say I've ever noticed the above 'facts'.

Nor me.

I have 23c and 25c on two different wheel sets and have swapped between them over a weekend. This is completely different, from a testing point of view, to riding one week with one tyre, buying new tyres the next weekend and convincing yourself they are much more comfortable.

Both of my tyre sets are GP4000S II.

Although for most criteria there really is nothing it, I greatly prefer the confidence of cornering on 23c. The rest is too negligible to notice.

The only thing that is not negligible is that my Cruds definitely won't fit over my 25c and these are on my Ksyriums which will soon be known as my winter wheels. If anyone in the Essex area would like to swap my barely used 25c with a set of similar worn 23c (also GP4000S II please) then drop me a PM.

What tyre pressures do you use in each case?
I'm curious why you have more confidence cornering on 23c? Is this down to familiarity, feel or some other reason?

23c = 90/100, 25c= 85/90psi. I am 76kg.

The confidence is from feeling that I can really load the 23c up in the corners and it will hold the line. The 25 feels softer in the corners and not in a good way. My 23 tyres are on 23mm wheels (FSE carbons), and my 25 tyres are 20.5mm wheels (Ksyrium Elites).