25mm or not

Kupe

What are all your thoughts? I am a bit indecided whether there is any gain in swaping out from 23mm tyres to 25mm.

indeterminate

you'll gain 2mm

cloggsy71

From what I am lead to understand, you will fractionally increase the rolling resistance, but the greater amount of air in the tyre helps to decrease the possibility of 'pinch flats'.

If the roads you ride are as rough as a badgers backside, it make sense to go with the larger girth of tyre; 25's or, if the frame/forks will take 'em, 28's for the real rough stuff!

My Cycling guru; TBY will be along shortly to confirm or dispel this info, but I'm sure this is correct :laugh:

Kupe

I waiting in anticipation for TBY input. I pose these question as I know he will always have some useful knowledge.

veloman21

I have experimented with this a lot, trying various brands of tyres, wheels and even running 23 on the front and 25 on the back.

I have changed over to 25c when at all possible and this winter may even run 28c on a new bike I will build uo.

I've found that 25c offers very palpable gains in comfort due to running at lower pressure and significant improvement in roadholding and cornering due to increased contact area. Some articles I've read have also stated that on rough road surfaces like chip seal, 25's actually roll faster than 23's.

For me and the riding I do (mostly hilly) 25c provides the best ride, the best handling, is the least fatiguing and I do not notice any reduction in speed at all. The only downside I have noticed is that the 25's do not climb as quite as well or accelerate quite as fast due to the slight increase in weight but the differences are tiny. The sure-footedness of the 25's on descents is very noticeable and most welcome though!!

The only issue I've come across is that on the new wave of wide sectioned wheels like my Boyd Altamonts which are 24mm wide, tyre widths grow considerably. So 23c on the Boyd's measure 25mm and 25c measure over 27mm. This is just a smidge too tight on my front fork and seat stays on my Cervelo. Most newer bikes have improved tyre clearance and I reckon 25c on the Boyds would be a killer combo.

My current favorite setup is my Dura-Ace C24 wheels shod with Schwalbe One 25c Tubeless tyres. The feel, comfort and grip is phenomenal.

TheBigYin

Well - thanks for the vote of confidence :-)

I'm another that's experimented with different tyre widths - when I came back to riding, 23c tyres seemed a little alien to me on a road bike - because, well, frankly 23c were generally training tyres - racing width stuff was 21c at mose, and 18/19 for time trials...

But, as I tried them, I thought "hey, they're not bad actually..." - and - as I was bloody enormous at the time - pushing 400lb - I soon swapped to a frame that would cope with something even wider - and was running 28c conti. Gatorskins front and rear.

As the weight came off, my craving for a bit more speed also increased, and I bought a 25c tyre to replace a worn out rear, doing a swap at the same time, so the 25 was front/old 28 from the front to the rear. Psychologically, it "felt" faster, though this wasn't really borne out by any hard and fast stats (or the "marginal gain" in the stats were masked by the "major gains" of losing 4lb a week and riding lots more!)

As the weights come off, I've sort of drifted down the tyre width scale and now don't really mind between 23-25c tyres. At the moment i've a pair of the 25c Schwalbe One's on the Ultegra 6700 wheels, but last spring/autumn I ran Vittoria Open Pave CG's in a 24c section which were not only wider but taller on the same rims.

And there's where we hit a bit of a problem... Tyre's aren't standard across different makes (often not even different ranges of the same make!). Continental's GP4000's for example - the 23c is actually a 22 and the 25c is a 24 - However IME the Gatorskins measure true to their branding...

FWIW, I can't honestly tell anything in terms of rolling resistance between 23 and 25 section tyres of the same make. I CAN however say that I get less pinch-punctures on the 25c section ones, and with the AWFUL road conditions we have around here (anyone who's seen some of the action-camera stuff I filmed knows what I mean) the 25c section ones make sense. If I was going for outright speed in a 10mile TT, then I'd cheerfully ride on 23c section Conti's at 150psi, but for my typical sunday century, i'd definitely be on 25's (and in winter quite possibly a 25/28 combo on the CaadX as clearances aren't really an issue on a road-ised Disk Braked Cross Bike...

TDSeest

I ran 38's for a major part of the summer, as my LBS ordered in the wrong tires. I normally run 28's. I didn't note any big difference in speed or drag. Definitely a more comfortable ride.

sufferlandrian

I switch from 23's to 25's this year. I don't notice any difference in drag but I get a lot fewer flats than I used to. Whether pinch flats or debris, I don't get the flats. There isn't enough weight difference in the tires to make a difference in climbing but the ride is just a bit smoother with running lower pressure (105 psi instead of 120 psi).

lpherman01

I made the switch this year and cannot recommend 25s highly enough. Except for glass smooth roads, which are few and far between, the 25s roll much better, with less resistance. More than a couple pros explained to me that running lower pressures (I run 15 psi less in the 25s) help the tires conform to and roll over the small irregularities in the road, as opposed to bouncing over them. They are noticeably smoother, and now that I have gotten over the "weenie" stage of not having skinny 23s, the 25s seem to look just right.