To those who made the switch from 23mm to 25mm...

Serious Cat

Can I ask which of the following outcomes would apply in your case.


a- Yes I noticed a worthwhile difference after making the switch and ill tell you what I liked in particular.

b- Cant really say whether I noticed anything positive or negative but ill just keep the 25`s and use them.

c- Preferred the 23`s to be honest and ill give you some details as to why.


Im kind of curious if a switch from 23`s to 25`s in my case will be a eureka moment or a letdown and id like to read some feedback from those who have taken the plunge.

nawty

Well firstly, one companies 25 can measure up the same as another's 23 so it isn't really easy to say much at face value.

However, I've see 23s, 24s and 25s and 32s and the biggest difference is due to the quality of the tyre, not the size. However, I do like the bigger tyres as riding along without really having to care what the road is like is one less thing to worry about and I don't notice any difference in speed.

Monty Dog

I switched about 12 years ago when the only 25mm option was Michelin Axial Carbons - the difference was noticeable not only in comfort but also in handling. A big round tyre at lower pressure has far more progressive handling on tight corners that a skinny one. If you continue to pump your 25mm tyres to 120psi then you've missed the point.

Serious Cat

I pump 120 psi into my 23`s monty, what are you pumping into your 25`s ?

nawty

I run my (nominally) 24mm Pave's at 90psi and when I use them I run 23's at around that too, maybe 100psi. I'm 75kg.

I can't imagine what running at 120psi is like, sketchy handling and crazy vibration I'd have though, unless you are well over 120kg!

Serious Cat

Running 23`s at 120 psi reduces snakebite punctures or so I am told.

wellbeloved747

23mm at 120psi, sketchy at times and rough, helps on the Devon hills though thats the main reason why

Miles253

Only after discovering this did I realise why I had some of the offs I did, couldnt figure out why I lost so much traction. Now I know

Ibis2k14

nawty wrote:

Well firstly, one companies 25 can measure up the same as another's 23 so it isn't really easy to say much at face value.

However, I've see 23s, 24s and 25s and 32s and the biggest difference is due to the quality of the tyre, not the size.

Agree 100% on both statements.

I like Conti tyres and I tend to use:

23mm GP4000s front and back, both at 100psi for uphills
23mm GP4000s front and 25mm 4 Seasons back, both at 100psi for commuting on flat

The reason why I use the mixed 23/25 for commuting is that I used to ride on 25mm Gatorskins but here in Taiwan punctures are not very common. I went for the 4 Seasons 25mm and a long piece of metal from a car accident cut the front tyre. At home I only had 23mm GP4000s as spares so I tried the mixed setup and I enjoyed it a lot.

robbo2011

I ran my Conti 4000s 23 mm at 90psi front and 100psi rear and never had a puncture. That set lasted for 10,000km.

Funnily enough, I've just changed them for Mavic Yksion Pro (as they were supplied with my wheels) and despite being less than 23mm, more like 21mm, they are more comfortable than the Contis. I'm running them at 100psi.

nawty

Serious Cat wrote:

Running 23`s at 120 psi reduces snakebite punctures or so I am told.

That much is true but you will be losing a lot of comfort, grip and also speed as the cost. My experience is that running as low a pressure as you can without getting pinches is a good rule of thumb - 120psi is waaaaaay high! - even for Devon hills, in fact especially for Devon hills (I've just done the Dartmoor Demon and I can't see any way in which high pressures would have helped).

Have a read of this:

http://www.bikequarterly.com/images/TireDrop.pdf

kajjal

I weight about 100kg and run my 23mm 4 seasons at 105psi. Seems fine to me and no problems with punctures. The only time I lost the bike was on gravel going too fast round a corner.

supermurph09

Surely the quoting of PSI is irrelevant without knowing rider weight.

cycleclinic

Do we have to hand hold here. if you want to try 25mm tyres do so it your own opinion that counts here and you wont have one until you try. The tyre it self make a difference to ride quailty grip e.t.c and who won't know which you like until you try them for yourself. Advise like this is always going to be biased one way or another you have stick with what you have or try something different.

Sometimes you just have to give things a go. there is no right and wrong with tyre pressures on pro's and con's and personal preference but to have personal preference you have to try different pressure first.

In short we all buy stuff which we don't like and then change to something different a review is simply someones opinion you need to have your own!

MattC59

I tend to use 23s, I've thought of switching to 25s, but the variance in size somewhat negates the need. Of course this variance is somewhat dependant on your rim.

I currently have 23mm Schwalbe Duranos on my Fulcrum Raciong Zeros, they measure in at a shade over 25mm.
Last summer I had 23mm Schwalbe Ultremo ZX on my Bontrager Aeolus 5.0, they measured in at a shade over 24mm.
I shall be putting my 23mm Veloflex onto my Racing Zeros as soon as the sh*te has been cleared from the roads, they measured up fairly accurately on my Aeolus, so it will be interesting to see what they measure up to on the Zeros.

The point being, measure your existing 23s, you might find that inreality they're actually 25s. If you do make a change to 25s, make sure that you keep the same model of tyre on the same rims, otherwise any comparrion is worthless.

lostboysaint

1.

markhewitt1978

GP4000S is a good compromise as I believe they are actually 24mm anyway, so a half way house - although I've never measured them.

MattC59

Serious Cat wrote:

Running 23`s at 120 psi reduces snakebite punctures or so I am told.

So does avoiding potholes !!!

I'm 84kg and run my tyres at 23mm 100 psi, I've never had a snake bite puncture on the road.

ai_1

Serious Cat wrote:

......Im kind of curious if a switch from 23`s to 25`s in my case will be a eureka moment or a letdown and id like to read some feedback from those who have taken the plunge.

I think you can be pretty sure that there'll be neither a dramatic Eureka moment or letdown. :roll:
Going with 25mm instead of 23mm in the same tyre will allow you run slightly lower pressure for slightly more comfort and slightly more grip with slightly more weight. I think it's a sensible choice, especially if you're not a very lightweight rider. However, it's not a life or death decision. There's been plenty of discussion on the topic and to be honest I hardly think there's any need for a poll to help you decide what tyre size to get..... but of course you can still have one if you want......

Bozman

25s - Bouncy feel to the ride, poor clearance and I can't use cruds with them, apart from that there's no difference but I'll stick with my 23s.

iron-clover

I'm sub 70kg and have always been running 23c tyres at 120psi. I use gatorskins for day to day riding, and they aren't inspiring on the corners (might try 100-110 for a while and see how it goes) but ride with them hard to try and deflect stones etc.
Though I've never had an 'off' in a corner, my cornering is utter rubbish because I think the tyres will let go fairly easily.

However, running gp4000s at their recommended 115psi gives far more confidence than the Gatorskins!

Unfortunately I've always been of the mindset that a harder tyre will roll faster as the contact patch should be smaller- but it now seems that may not be the case...

markhewitt1978

iron-clover wrote:

Unfortunately I've always been of the mindset that a harder tyre will roll faster as the contact patch should be smaller- but it now seems that may not be the case...

On a perfectly smooth surface, that would be true!

edhornby

moving from a 23 to a 25 gatorskin improved the grip (rear not front) and feel ok

still undecided what to have on the front. still using a 23mm lithion because that's what I had in the spares box, good grip and feel but not as immune to punctures as a commuter tyre should be and I'm happy to go for something posh and probably 25mm; cheap tyres on a bike that shares roads with cars I do not do

got a crud on without any bother - next winter will be proper SKS and p-clips [edit] I'm 73kgs and run at 7bar front and rear

markhewitt1978

I had SKS Raceblade long on during the winter running with GP 4 Season 23mm. But when I fitted my GP4000S back on they wouldn't fit, the bracket under the brake capliper was rubbing on the tyre. Would be good to know if crud roadracers would fit.

duckson

I'm running 23c gp4000s on my temp wet bike (Spesh Allez) and they just fit although I've taken the nose off as it catches a bit.

Just bought some Veloflex Corsa 25c to try instead of GP Force/Attack on my best bike with DA9000 C24's.

rmw

I've just changed from running Ultremo's 23mm @120psi to GP4000s 25mm @110psi.

A very windy first ride on them yesterday and the main difference I noticed is the comfort. Rolling resistance appeared similar and although the Ultremo's 23mm gripped well and inspired confidence through fast corners I am certain that the GP4000s are even more impressive.

Early days yet – but if they wear well – and the puncture resistance is as good as the Rubino Pro's I've used in the last 3 years – I might just stick with them.

ic.

I changed to 25mm GP4000s a few hundred miles ago. But I didn't run 23mm GP 4000s before that, so I can't compare.

What I can say is I had road tubeless for a while, since switching to tubed 25mm I can't tell I great deal of difference.

FYI I run them 10 psi lower than 23mm

I would rate these tyres as the best I have ever ridden without doubt. That list includes Ultremo ZX, Ultremo Tubeless, Durano, Lugano and Mavic Yksion

mfin

iron-clover wrote:

I'm sub 70kg and have always been running 23c tyres at 120psi. I use gatorskins for day to day riding, and they aren't inspiring on the corners (might try 100-110 for a while and see how it goes) but ride with them hard to try and deflect stones etc.
Though I've never had an 'off' in a corner, my cornering is utter rubbish because I think the tyres will let go fairly easily.

However, running gp4000s at their recommended 115psi gives far more confidence than the Gatorskins!

Unfortunately I've always been of the mindset that a harder tyre will roll faster as the contact patch should be smaller- but it now seems that may not be the case...

Pressure is somewhat proportional to weight, you're running too high. 100psi should be about the max on 23's for your weight really.

Slo Mo Jones

I noticed absolutely no difference.

marcusww

100kg rider, 25mm gatorskin on the back 120psi and 23 Ultremo ZX on the front 110 psi. This was a chance matching and find this fast in the dry.

cycleclinic

23mm GP4000s have no recomended tyre pressure they have a max tyre pressure of 115psi but that is by no means what you should run them at. Again experiment with pressures. Also once you get used to gatorskins you will find you push into the corner very hard and they don't let go, they may not inspire confidence you just need to commit.