25c won't fit!

[2ky]

Just tried fitting some new Continental GP4000s II tyres to my Cube Agree and the front tyre is catching on the front brake (Very lightly but too much to ignore!).
The bike had Mavic tyres on before and they were fine (700x25c) but Continental's seem to be a tiny bit higher on the rim.
Does a 23c tyre have a slightly lower height than a 25c?

[Banana Boy]

You don't fancy getting the Dremel out then?!...

[mcelliott]

Yep I'm sure 23s have a slightly lower profile so should fit. I actually run 20mm on my training bike which are just as puncture resistant in my opinion, or you may prefer the slightly better ride comfort offered by the wider tyre. Failing that, the Continental Attack tyre, which is very similar to the GP4, comes in 22mm.

[benny.c]

I've got some used 23's (maybe 500 miles) if you fancy a swap with some cash your way.

[jamiebae]

Rim width makes a difference too. I was running Michelin Pro4 in 25c on one of my bikes with no problems, I changed the wheels to some Cosine ones with slightly wider rims and the tyre would foul the top of the fork. I ended up having to dig out some old 25c Contis which did fit OK so not all tyre brands are the same.

[nammynake]

GP4000s 25mm are pretty big, certainly bigger than most other 25mm tyres. There is quite a variation in size across different brands even though they're all quoted as 25mm.

[paulmon]

I had the same problem with my CAAD10. E-bay the tyres or a new bike is the only solution.

[jamiebae]

paulmon said:

I had the same problem with my CAAD10. E-bay the tyres or a new bike is the only solution.

Strange, I've run a couple of different 25c tyres on new Ultegra wheels on my CAAD10 with no issues at all - Veloflex Master and Vittoria Open Pave

[astroarcadia]

GP4000s at 100psi -

23c are 25mm wide, 23mm high
25c are 27mm wide, 25mm high
28c are 31mm wide, 29mm high

[paulmon]

jamiebae said:

Strange, I've run a couple of different 25c tyres on new Ultegra wheels on my CAAD10 with no issues at all - Veloflex Master and Vittoria Open Pave

Have you tried the gp4000's the op mentioned? In hot conditions they collect stones and get trapped between the tyre and the calliper.

[jamiebae]

paulmon said:

jamiebae said:

Strange, I've run a couple of different 25c tyres on new Ultegra wheels on my CAAD10 with no issues at all - Veloflex Master and Vittoria Open Pave

Have you tried the gp4000's the op mentioned? In hot conditions they collect stones and get trapped between the tyre and the calliper.

Nope, but was thinking about trying them next time so might give them a miss!

[Matt_N]

astroarcadia said:

GP4000s at 100psi -

23c are 25mm wide, 23mm high
25c are 27mm wide, 25mm high
28c are 31mm wide, 29mm high

What rim?

They don't measure the same on an Open Pro and an Archetype for example.

[Fourmotion]

Those particular tyres come up very big. I can run Conti 4 seasons in my S5 no problem, but the GP4000s will rub the chain stay. They're the same pissing manufacturer!!

Vittoria Open Pave 27c fit.

If you want the tyres I'd size down to 23c.

[rhinochopig]

Conti's seem to have THE worst tyre sizing when it comes to consistency. They really a joke. I have them on most of my bikes and they're either huge compared to as sold or tiny. Case in point a set of 2.4" Mountain Kings come up as under 2" wide on an XC rim and bob on "2.2 on a full fat DH rim.

It REALLY REALLY annoys me as I think Conti make the best MTB and road bike tyres on the market in terms of grip, wear, and handling.

Edited by rhinochopig on Monday 25th April 12:52

[esuuv]

I've only ever run 23 GP4000 2's on my Scott Foil - I tried 25's once and they caught the bridge of the fork slightly.

I also tried running 25's on my P5 that the internet assured me would fit and they caught the downtube of the frame - so 23's all round.

I've just fitted some 23 gatorskins as i'm sick of punctures on my roadbike and they are tiny - would have easily got 25's on - so basically GP4000's are very big for their size.

[astroarcadia]

Matt_N said:

astroarcadia said:

GP4000s at 100psi -

23c are 25mm wide, 23mm high
25c are 27mm wide, 25mm high
28c are 31mm wide, 29mm high

What rim?

They don't measure the same on an Open Pro and an Archetype for example.

700 x 17c
Conti Race28 tubes.

[2ky]

23c arrived and fits perfectly

The difference between the 25c on the back and 23c is huge. Oh well, at least it's comfy!