25mm Tyres on Ribble New Sportive rubbing at back?

bus_ter
bus_ter Posts: 337
edited August 2013 in Road general
So I swapped to 25mm Continental GP4000S tyres for a more comfortable ride (and after all the recent talk about them actually being quicker than 23mm on rough roads) and after a thousand miles or so it looks like the rear tyre has been rubbing against the frame. The clearance is close but I thought it was ok. However I've noticed some of the rubber coming off the tyre sidewalls at their widest point revealing a hint of the tyre carcass underneath. I've found that if I flex the back wheel I can make it rub the frame and thus that must be what's been happening on out of saddle efforts.

This is both asking a question to see if other Ribble New sportive owners have noticed this with 25mm tyres and also a warning to other owners to be careful with 25mm tyres..

Comments

  • smoggysteve
    smoggysteve Posts: 2,909
    Not all frames are compatible with 25mm tyres. Problem is, they don't always tell you this and you only find out when you fit some.

    BTW, the 25mm faster than 23mm is pish and has no solid evidence to support it. Its more down the the pressures ran in the tyre than the width. For every argument that says they are faster cos they put more rubber down, there is an argument says this just causes more rolling resistance. Until someone comes on here with undeniable proof then I will ignore them and only use them for comfort if at all.
  • brindlescoops
    brindlescoops Posts: 465
    Yes I am afraid they are just too wide, I did exactly the same with 25mm GP4000s tyres without even using them and had to go back to 23mm on my Ribble Buanco :(
    My biggest fear is that should I crash, burn and die, my Wife would sell my stuff based upon what I told her I paid for it.
  • pinarellokid
    pinarellokid Posts: 1,208
    yep me too, my new sportive wont run 25's
    Specialized S Works SL2 . Campagnolo Record 11spd. rolling on Campag Zonda wheels

    http://app.strava.com/athletes/881211
  • tomisitt
    tomisitt Posts: 257
    SmoggySteve, there's plenty of solid evidence to show that 25s are faster than 23s. Wider tyres actually have less rolling resistance. Have a look at March 2013 issue of Cyclist mag for a really interesting article on the subject. Techies from all the major manufacturers agree, wider is faster up to around 26, when weight and aerodynamics come into play. 24 is reckoned to be the optimum size.
  • smoggysteve
    smoggysteve Posts: 2,909
    tomisitt wrote:
    SmoggySteve, there's plenty of solid evidence to show that 25s are faster than 23s. Wider tyres actually have less rolling resistance. Have a look at March 2013 issue of Cyclist mag for a really interesting article on the subject. Techies from all the major manufacturers agree, wider is faster up to around 26, when weight and aerodynamics come into play. 24 is reckoned to be the optimum size.


    Show me where to find it. Somewhere that irrefutably shows this is true. Not just schmoes on forums saying so.
  • smoggysteve
    smoggysteve Posts: 2,909
    Also, considering there are bike makes that don't even accept them they cannot be that performance enhancing can they?
  • smoggysteve
    smoggysteve Posts: 2,909
    http://roadcyclinguk.com/news/racing-news/25mm-tyres-tested.html

    See, depending on where you read you get a different opinion. 3rd paragraph says it all. So that is not solid proof to me.
  • adr82
    adr82 Posts: 4,002
    SmoggySteve wrote:
    Also, considering there are bike makes that don't even accept them they cannot be that performance enhancing can they?
    By that "logic" an electric motor cannot be performance enhancing either since you can't easily slap one onto your bike. Anyway, you're missing the point - the idea that 25mm can be better than 23mm is a relatively recent development, so it's hardly surprising that many frames haven't been designed for the wider tyres. If they start becoming much more popular, I'm sure frames will change to fit them.
    SmoggySteve wrote:
    http://roadcyclinguk.com/news/racing-news/25mm-tyres-tested.html

    See, depending on where you read you get a different opinion. 3rd paragraph says it all. So that is not solid proof to me.
    Let's see what it says, shall we?
    Despite this, the 25c format is too fat for racing. The width of the tyre increases frontal area and air drag, ruling it out for time trials on smooth roads. The increased weight is a significant handicap in any acceleration, so they aren’t much use in a bunch.
    Wow, that's pretty irrefutable alright, case closed... oh wait, no it isn't! Exactly where is their "solid proof" to back these statements up? Or is such proof only required for things you disagree with? Surely not!

    Sounds like handwaving crap to me... maybe they have a point about TTs, although I suspect that your riding position/wheels/frame geometry would be much more important aerodynamically. But in a bunch, where you're sitting inches away from the wheel of the guy in front? I find it very hard to believe a slightly wider tyre is going to make any real aerodynamic difference in that situation. Also had a good laugh at the "increased weight" being a "significant handicap", that's hilarious - out of interest I just checked how much weight difference there is between the 23 and 25mm version of my current tyres: a whopping 10g :shock: :lol:
  • smoggysteve
    smoggysteve Posts: 2,909
    adr82 wrote:
    Let's see what it says, shall we?
    Despite this, the 25c format is too fat for racing. The width of the tyre increases frontal area and air drag, ruling it out for time trials on smooth roads. The increased weight is a significant handicap in any acceleration, so they aren’t much use in a bunch.
    Wow, that's pretty irrefutable alright, case closed... oh wait, no it isn't! Exactly where is their "solid proof" to back these statements up? Or is such proof only required for things you disagree with? Surely not!

    I don't know if you really are that dumb , but thats my point. There is no SOLID PROOF either way. Did I put this up to show its not true or to show there is a contradiction in opinions from other sources? RTFQ dumbass
  • smoggysteve
    smoggysteve Posts: 2,909
    RCUK journalist Vs Forum Cockstand - I think I know which one I trust the opinion of more
  • adamfo
    adamfo Posts: 763
    SmoggySteve wrote:
    http://roadcyclinguk.com/news/racing-news/25mm-tyres-tested.html

    See, depending on where you read you get a different opinion. 3rd paragraph says it all. So that is not solid proof to me.

    That article is 5 years out of date.The fast boys do not ride 23

    http://www.youtube.com/watch?v=LdpyKgxEjZA

    http://www.youtube.com/watch?v=OjKFEGNK6aI

    http://www.youtube.com/watch?v=r-id5__Ci98
  • tomisitt
    tomisitt Posts: 257
    SmoggySteve...show you where to find solid proof? RTFA, dumbass. Cyclist magazine (March 2013 issue). Here are some quotes from non-forum schmoes in the article:

    Schwalbe product manager Marcus Hachmeyer:
    ‘If you compare tyres with different widths but identical specs – same compound, same rounded profile, same inflation pressure – one can say in terms of rolling resistance: the wider the faster.’

    "Analysis of a tyre’s contact patch has helped designers such as Hachmeyer see past the popular belief that ‘narrower equals faster’."

    Christian Wurmbäck, Product Manager at Continental:
    ‘Wider tyres are faster. A 24mm rolls faster than a 23mm, but a 25mm tyre rolls even faster than that. In fact, our GP4000s tyre is around 7% faster in a 25mm than a 23mm version.’

    Nicolas Cret, Product Manager at Michelin:
    ‘Although a 28mm tyre will be quicker than its 23mm version in terms of rolling resistance, the weight of the 28mm will be higher than the 23mm as a bigger size means more material. This is likely to create a noticeable difference in terms of inertia, and it will have an effect during acceleration or deceleration phase. Aerodynamic properties will also change from a 23mm tyre to a 28mm.’

    Wolf VormWalde, Tyre Product Manager at Specialized:
    ‘We’ve found 24mm is the ideal compromise in rolling resistance, aerodynamics and weight.’

    So experts from Schwalbe, Michelin, Continental and Specialized are all agreed. I realise that expert opinions from the world's leading tyre manufacturers do not constitute "solid proof", but I'm prepared to take their word for it. RCUK Journalist v people who actually design and make tyres - I think I know which one I trust the opinion of more.
  • adr82
    adr82 Posts: 4,002
    SmoggySteve wrote:
    adr82 wrote:
    Let's see what it says, shall we?
    Despite this, the 25c format is too fat for racing. The width of the tyre increases frontal area and air drag, ruling it out for time trials on smooth roads. The increased weight is a significant handicap in any acceleration, so they aren’t much use in a bunch.
    Wow, that's pretty irrefutable alright, case closed... oh wait, no it isn't! Exactly where is their "solid proof" to back these statements up? Or is such proof only required for things you disagree with? Surely not!

    I don't know if you really are that dumb , but thats my point. There is no SOLID PROOF either way. Did I put this up to show its not true or to show there is a contradiction in opinions from other sources? RTFQ dumbass
    Nice backpedaling :)
  • drlodge
    drlodge Posts: 4,826
    I can think of 3 factors relative to width:
    - width itself, which impacts on rolling resistance. May be 25c does have lower rolling resitance than 23c ad 28c less than 25c, but there does it end...how much rolling resistance would a 1 mile wide tyre have? A lot would be my guess so there has to be a "sweet spot", where is that spot?
    - volume. Increasing width increasing the volume of the tyre which means lower pressures can/should be used. Lower pressures mean more comfort. Of course lower pressure also impacts on the rolling resistance so while a 25c on 100psi may have less rolling resistance than a 23c on 100psi its not a fair comparison since the 25c should have may be 10-20 psi less than then 23c tyre
    - air resistance. The wider the tyre, the greater is frontal area and therefore greater wind resistance. Therefore thinner is better (all other things being equal).

    I've got 23c GP4000S one the Rourke and 25c GP4Season no the Condor. I can certainly tell the wider GP4S is more comfortable (they replace 23c Gatorskins so may be its down to the different construction than the width), I have no idea if its more efficient or not. Probably unelss you're racing, 25c is a good all round compromise for everyday training, sportives etc. But some bikes can't take 25c tyres.
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • pkripper
    pkripper Posts: 652
    drlodge wrote:
    - air resistance. The wider the tyre, the greater is frontal area and therefore greater wind resistance. Therefore thinner is better (all other things being equal).

    Not quite, as that's all dependent on the tyre / rim interface, and also the amount of shielding the frame can offer. A thin tyre on a wide rim will not perform as aerodynamically well as a tyre whose profile can be matched to the rim.

    Aero frames that hug the back wheel are also more effective working with a back tyre that minimises the drag created by this interface, and that's entirely frame specific.
  • adamfo
    adamfo Posts: 763
    The German magazine 'Tour' publish tyre rolling resistance figures obtained from a rolling road. They also test tyre/wheel aerodynamic figures in a windtunnel.
    Suffice to say what pkripper says above is correct. SmoggySteve appears to be based in Germany so one can only wonder at his lack of data acquisition capability !
  • pitchshifter
    pitchshifter Posts: 1,476
    Yawn. Seriously arguing over 2mm?

    Want to ride faster? Ride more! 25mm will be more comfortable but any performance gain is probably negligible, certainly not noticeable on the road.
  • smidsy
    smidsy Posts: 5,273
    I think the actual claim is that 25mm tyres have less rolling resistance than 23mm ones, not that they are faster specifically.

    A tyre does not have any speed, that comes from the rider ;-)

    Anyway my CAAD 5 takes 25mm tyres AND still has room for Crudcatcher mudguards, and that is 10 years old.

    Way to go Cannondale :-)
    Yellow is the new Black.
  • ferdifatcat
    ferdifatcat Posts: 24
    I use 25mm tyres on my new sportive racing, ( for the last 2 years) no problem at all. Are you sure your wheel is not buckled ?
  • bus_ter
    bus_ter Posts: 337
    Thanks for the replies. Interesting to see comments of people who have used 25mm ok on the frame and others who have found they don't quite fit. I originally thought mine were ok but they have been rubbing at the sides during wheel flex. My conclusion here is that 25mm is on the absolute limit. Depending on the wheels (rim width, stiffness, trueness etc) and the tyres (different brands of 25mm tyres can vary in size) you may or may not get away with it.

    The rubber on the edges of my tyres have been rubbing away, also the clear coat on the frame shows signs of rubbing. I'm going to play it cautious and drop back to 23mm tyres, I'm also going to take the back wheel into the LBS to have the tension/trueness checked.

    FYI I've been using Continental GP4000S on Shimano RS-80 wheels
  • smidsy
    smidsy Posts: 5,273
    RS80 wheels...flex....but they are super stiff!!

    Oh hang on that is other peoples opnion - I have been trying to say they are not all that for ages.

    Conclusion - get better wheels and run 25mm tyres.
    Yellow is the new Black.
  • dennisn
    dennisn Posts: 10,601
    SmoggySteve wrote:
    tomisitt wrote:
    SmoggySteve, there's plenty of solid evidence to show that 25s are faster than 23s. Wider tyres actually have less rolling resistance. Have a look at March 2013 issue of Cyclist mag for a really interesting article on the subject. Techies from all the major manufacturers agree, wider is faster up to around 26, when weight and aerodynamics come into play. 24 is reckoned to be the optimum size.


    Show me where to find it. Somewhere that irrefutably shows this is true. Not just schmoes on forums saying so.

    I'm with you on the "show me....". I've got the feeling that "tomisitt" relies on, so called, Internet truth, and tire manufacturer's claims of wonderous things.
  • tomisitt
    tomisitt Posts: 257
    tomisitt is a journalist with 30 years experience in consumer journalism (cars, bikes and powerboats) so is probably more sceptical than most. However, I do read other actual magazines, and the quotes I posted are attributed to actual experts interviewed by actual journalists rather than random stuff from the web.

    If experts from Michelin, Conti, Specialized etc say that the optimum size for a tyre is 24mm, I have no reason to disbelieve them (it's not as if they all have warehouses full of unsold 24s they need to shift). The article in question went into the science behind their assertions, and raised some very interesting points. If you want to be shown, I suggest you start there.
  • smoggysteve
    smoggysteve Posts: 2,909
    What sort of person talks about himself in the 3rd person? Delusions of self importance?
  • dennisn
    dennisn Posts: 10,601
    tomisitt wrote:

    If experts from Michelin, Conti, Specialized etc say that the optimum size for a tyre is 24mm, I have no reason to disbelieve them (it's not as if they all have warehouses full of unsold 24s they need to shift).

    Sorry, but I'm a whole lot more skeptical than yourself. Your "..I have no reason to disbelieve...." and "...if experts from..." statements seem, to me, to show a bit of naivete on your part. For one thing it's not the experts who are saying these things. It's the ad men. For me it's all about selling something different. Sort of like stems and bars. Of course you need a 31.8 bar and stem set as opposed to the one you currently have because it's "better", but the real reason you need one is to enrich the coffers of the manufacturer's. The don't make a dime if you don't buy a new set and the only way to sell you one is to claim that it's "better" and a must have part.
  • tomisitt
    tomisitt Posts: 257
    Yes, but you are simply choosing between a 23 or a 25, so it makes little difference to them which one you buy. I agree that this business is full of people trying to convince you (or convince themselves) that you need electronic shifting, tubulars, disc brakes, etc. Have a look at the article, it's pretty interesting.
  • Jon_1976
    Jon_1976 Posts: 690
    I stopped reading the thread after it descended into the usual 'anyone who doesn't agree with my opinion is dumb' bollocks. To the op: Tyre widths vary greatly between different manufacturers and also in the different model lines. In my experience (on my Allez):
    25mm Specialized Espoir tyres: difficult to remove through brake calipers.
    25mm Conti GP4000 tyres: impossible to fit/remove through calipers. Required deflating.
    25mm Specialized Turbo Pro: pass through the brakes easily with visible room to spare.

    All at same pressure.
  • dennisn
    dennisn Posts: 10,601
    Jon_1976 wrote:
    I stopped reading the thread after it descended into the usual 'anyone who doesn't agree with my opinion is dumb' ****.

    I think you're missing the point of the title of all of this. "FORUM". It's what people do in forums. We push our views to other people. Most of the time we feel that we are right in what we say. Others may not be so sure about our reasons and speak out with their own ideas. Does some of it get down and dirty? Sure.

    YOU have a choice as to whether to read or not. Or even whether to post or not.
  • bus_ter
    bus_ter Posts: 337
    Jon_1976 wrote:
    I stopped reading the thread after it descended into the usual 'anyone who doesn't agree with my opinion is dumb' ****. To the op: Tyre widths vary greatly between different manufacturers and also in the different model lines. In my experience (on my Allez):
    25mm Specialized Espoir tyres: difficult to remove through brake calipers.
    25mm Conti GP4000 tyres: impossible to fit/remove through calipers. Required deflating.
    25mm Specialized Turbo Pro: pass through the brakes easily with visible room to spare.

    All at same pressure.

    Thanks Jon that's useful. Looks like I might be able to get away with other 25mm tyres without issue.

    I've since (yesterday) swapped them out for 23mm Conti 4 season tyres. Lots of clearance now and I thought they might be a better choice now we're coming into Autumn.
  • Jon_1976
    Jon_1976 Posts: 690
    bus_ter wrote:

    Thanks Jon that's useful. Looks like I might be able to get away with other 25mm tyres without issue.

    I've since (yesterday) swapped them out for 23mm Conti 4 season tyres. Lots of clearance now and I thought they might be a better choice now we're coming into Autumn.

    You're welcome mate. Good choice on the 4 seasons, at least you're prepared for the colder/wetter seasons :) I hope they solve your frame rubbing problem.

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