23's or 25's

woo1

I was initially just debating to get the GP 4000s or the Pro4 Service Course, now it looks likethe size seems to be a talking point. Decisions, decisions...

Is there any major difference between the 23' & 25'

Is it a case of the 23 is faster but less comfortable & 25 is slower but more comfortable, or is just down to the PSI and there is no difference ?

Input appreciated

markhewitt1978

23 is slower and less comfortable.
25 is faster and more comfortable.

imposter2.0

markhewitt1978 wrote:

23 is slower and less comfortable.
25 is faster and more comfortable.

really?

Bordersroadie

Yes, it's true. And hardly a few grammes in extra weight.

Do a search, there's loads of threads and links on this subject.

imposter2.0

Bordersroadie wrote:

Yes, it's true. And hardly a few grammes in extra weight.

It's not quite as simple as that...

rolf_f

Imposter wrote:

markhewitt1978 wrote:

23 is slower and less comfortable.
25 is faster and more comfortable.

really?

No, not really as far as the speed thing is concerned - at least not in any real world measurable sense. Theoretically, the 25 is faster for the same pressure as the contact patch is shorter in the direction of movement. But, of course, the pressure you use is affected by both your tyre choice and your own weight so it isn't quite that simple. In practice it's only worth thinking about which you find more comfortable and normally that is the 25. But if you are light, then you can run lower pressures on the narrower tyre for the same effect. The best answer is to try what you haven't tried before and see if you prefer it or not!

I normally use 23mm because 25s don't fit easily under my Crud Racer mudguards on my Ribble and it's easiest to stick to the same on all bikes. And they weigh less which is vitally important!

dwanes

markhewitt1978 wrote:

23 is slower and less comfortable.
25 is faster and more comfortable.

Not true.

25's are more comfortable, but not faster.

DiscoBoy

dwanes wrote:

markhewitt1978 wrote:

23 is slower and less comfortable.
25 is faster and more comfortable.

Not true.

25's are more comfortable, but not faster.

As with all of these things, it depends. On some rims (usually wide ones) 25mm is more aero.

Additionally, 25mm tyres roll more smoothly and, in my experience at least, smoother is faster

smidsy

dwanes wrote:

markhewitt1978 wrote:

23 is slower and less comfortable.
25 is faster and more comfortable.

Not true.

25's are more comfortable, but not faster.

Less rolling resistance rather than faster, but even that is hotly debated.

IME 25's offer a nicer ride and that is more important to me than speed.

slowbike

I use 23's on my wifes and my own bike - 23's because 23's just fit between the chainstays of my best bike - 25's may fit, but it'll be tight ... and being tight means I can swap wheels/tyres out from my wifes bike if I trash my tyres!

Grill

Let's not forget that narrower tyres tend to be more aero... :P

dwanes

Yes, so next time you are ploughing down those country lanes, you are going so fast all because your 25mm tyres are more aero.

Grill

dwanes wrote:

Yes, so next time you are ploughing down those country lanes, you are going so fast all because your 25mm tyres are less aero.

Fixed that for you

Moonbiker

I'd go for 25mm if they fit your bike, unless the roads round you are perfectly surfaced.

Read this:

http://inrng.com/2013/04/reinventing-the-wheel-25mm/

These days Argos-Shimano, Blanco, BMC Racing, FDJ, Omega Pharma-QuickStep, Orica-Greenedge, Radioshack-Leopard and Sky are running 25mm. Why? Well increased grip is one explanation. But there’s more to it. Here’s one reason:

We went from 21mm and 23mm to 25mm tyres in the last few seasons; new research shows that 25mm have less rolling resistance and I have the feeling they give more comfort and traction so it’s a win-win situation
- Koen de Kort, Argos Shimano speaking to RIDE Cycling Review, Issue 59, p95.

Noticed planet X are selling 20mm really tyres cheap I suppose are out of fashion?

Have an old peugeot with 20mm Rubinos @ 120psi on from the 1980's bit of a rough ride over bad roads, was thinking of buying some 28mm tyres for it to put on when 20mm ones have worn out.

rickeverett

23's like Continental GP4000 are very comfortable and fast.

running the same pressure on a 23 and 25 - the 23 has a smaller contact area.

markhewitt1978

rickeverett wrote:

23's like Continental GP4000 are very comfortable and fast.
.

You mean GP4000S? I believe the 23's are actually more like 24s. I run them and agreed they are good and comfortable.

dodgy

I recently went from 23mm Pro Race 3 to 25mm Pro Race 4. I don't think they're faster or slower, about the same I reckon. I can't feel that much benefit in comfort, but there is a small improvement. The biggest benefit is more confidence over very bad surfaces.

I went to 32mm tyres on a new winter trainer (Alfine Day One), and again, that isn't that much slower. At least, nowhere near as slow as I was anticipating. Comfort is in a different league, superb!

MattC59

What rims are you running them on ? What pressure are they at ? What is the road surface like . How heave are you ? In the real world there are a ton of variables which will effect the 'speed' and comfort of your tyre.

23mm Ultremos measure in at just over 24mm on my Aeolus rims. Does that mean they have the comfort of a 23 or a 24 ?

Bozman

I bought some 25s last month and I've been out on them a couple of times, I found them comfy with quite a spongy feel. I prefer the 23s and I was glad to be back on them, they just seem to give you a better feel on the road.
When you put a wheel with 25s on next to one with 23s on, the 25s look huge almost ugly on a road bike.

Grill

markhewitt1978 wrote:

rickeverett wrote:

23's like Continental GP4000 are very comfortable and fast.
.

You mean GP4000S? I believe the 23's are actually more like 24s. I run them and agreed they are good and comfortable.

They're 23.8. They used to be marketed as 24c. Good tyre though.

il sole

For what it's worth, i've just switched from 23 to 25...I'm pretty much a novice, only having bought my first road bike last september (at the age of 38 - why didn't i do it sooner??!!)...
I bought a second hand Wilier Mortirolo from a friend. I found that the 23mm gatorskins he had on it were excellent at preventing punctures, but not great for grip and comfort. I've switched to conti 4 seasons on 25mm and the difference is huge. I accept that a lot of this is down to softer sidewalls, however, the extra grip from the wider tyre has increased my overall speed no end. I would also add that as a recreational cyclist who averages about 50-60 miles a week, the added comfort from the 25s has been well appreciated!!

kajjal

It's personal preference, I ride 23's as they feel right to me on the road. My XC mountain bike has much larger tyres which feel right off road, on road they will go over anything.

ugo.santalucia

An interesting way to spend an afternoon... there is no difference

Serious Cat

As is typical of internet forums.

Q: Which is better A or B ?


A: I think A is better than B

A: I think B is better than A

A: I think there is no difference between A and B


Some things just never change and I think the answer to so many comparison questions posted here is go out and try the gear for yourself . and buy the one you prefer.

Father Faff

So if bigger tyres are faster why don't people put 28mm or bigger on their bikes?

cycleclinic

My23mm GP4000s are 26mm width on 25mm wide carbon rims. Tyre width is dependent of rim width. I personally would ride tyres as wide as you can but be aware some tyres in 25mm form come up no wider than the 23's thus giving no avantage. One example is the Gatorskin hardshell, the 25mm tyre is no wider than the 23mm on a 15mm internal width rim.

Having tried all kind of tyre widths I can say there is no difference in speed between 23mm and 25mm tyres. You may start to notice the increased mass in tyres that are much wider (well you will). Also tyres beyond 30mm tend to the the touring or commutor type, i.e puncture resistant which means a less supple casing.

There is far more to a tyres rolling friction than width. In fact if you read bicycle science edition 3 there is a good treatment of this and tyre width has a very miminal effect. The test that are often done on tyre width are done with constant pressure but when did anyone run a 28mm tyre with the same pressure as a 23mm tyre this make such test invalid in the real world . Tyre casing construction and pressure have a much bigger effect on rolling resistance.

smidsy

Father Faff wrote:

So if bigger tyres are faster why don't people put 28mm or bigger on their bikes?

I though we covered this - all tyres are the same, they do not have any speed.

It may be possible to claim less rolling resistance for a given pressure (depending on all sorts of factors) between sizes, but speed comes from the engine.

rolf_f

smidsy wrote:

It may be possible to claim less rolling resistance for a given pressure (depending on all sorts of factors) between sizes, but speed comes from the engine.

And drivetrain efficiency has nothing to contribute? I have a sneaking feeling if you filled your cars gearbox with sand it would travel quite a lot slower despite the engine being the same!

smidsy

Rolf F wrote:

And drivetrain efficiency has nothing to contribute? I have a sneaking feeling if you filled your cars gearbox with sand it would travel quite a lot slower despite the engine being the same!

Not relevant. We are talking about tyres having speed. :roll:

rolf_f

smidsy wrote:

Rolf F wrote:

And drivetrain efficiency has nothing to contribute? I have a sneaking feeling if you filled your cars gearbox with sand it would travel quite a lot slower despite the engine being the same!

Not relevant. We are talking about tyres having speed. :roll:

No need for the sarcastic smiley.
Apols for the over complicated analogy (that's all it was - an analogy). Yes - tyres do have speed. There are differences in rolling resistance between different tyres even if it is pretty insignificant. You aren't really helping things by providing incorrect explanations - the point being (which I think we agree on) that the difference in rolling resistance between different tyres, whether down to compound or shape/size is not really significant compared to perception of ride quality.

smidsy wrote:

It may be possible to claim less rolling resistance for a given pressure (depending on all sorts of
factors) between sizes, but speed comes from the engine.

Do you seriously believe that rolling resistance has no impact on speed?

buckles

At racing speeds rolling resistance becomes insignificant compared to air resistance or gravity