23mm vs 25mm tyres - clearance

secretsam
secretsam Posts: 5,120
edited May 2014 in Workshop
OK, so someone's asked about radius of 25s vs 23mm, but what about overall height? My Cinelli being typically Italian doesn't allow for pansy things like fatter tyres, so I've only got 3-4mm space around my (winter) Vittoria Zaffiros - could I fit 25mm if I wanted? Not sure how 'big' bigger tyres are? My 28mm on other bikes are mahoosive in comparison...
It's just a hill. Get over it.

Comments

  • manglier
    manglier Posts: 1,277
    I have just measured up my Michelin Pro 4 Endurance 23 & 25mm tyres. The 23's are 21.5mm from tread to rim and the 25's are 27mm, a difference of 5.5mm. However that's on a Dura Ace C24 rim, perhaps a wider rim will give a lower height.
  • secretsam
    secretsam Posts: 5,120
    Ah. Bum. Oh well, thanks anyway (how are the Pro 4s? I'm going to put some on my bike soon! Loved the Pro 3s)
    It's just a hill. Get over it.
  • Matthewfalle
    Matthewfalle Posts: 17,380
    Doesn't it all depend on the individual tyre though? I remember on here a big discussion about tyres that were meant to be a 25 but were a 23 and ones that were meant to be a 25 but were ad infinitum.

    Maybe worth getting, trying on and if they don't work (all you have to do is fit and spin the wheel by hand so no need to get dirty and give the game away) send back?
    Postby team47b » Sun Jun 28, 2015 11:53 am

    De Sisti wrote:
    This is one of the silliest threads I've come across. :lol:

    Recognition at last Matthew, well done!, a justified honour :D
    smithy21 wrote:

    He's right you know.
  • jotko
    jotko Posts: 457
    Dunno what Cinelli you have but I am running 25mm Rubino Pros on open pro rims on my Cinelli Saetta with no issues. No way 28s would fit, but 25s are fine.
    strava - http://app.strava.com/athletes/1217847
    trainerroad - http://www.trainerroad.com/career/joeh
  • ai_1
    ai_1 Posts: 3,060
    Manglier wrote:
    I have just measured up my Michelin Pro 4 Endurance 23 & 25mm tyres. The 23's are 21.5mm from tread to rim and the 25's are 27mm, a difference of 5.5mm. However that's on a Dura Ace C24 rim, perhaps a wider rim will give a lower height.
    25mm Michelin Pro 4 tyres are not really 25mm it would seem. I came across the following review last week when considering picking up a pair. Seems the "25s" are really more like 28s.
    http://www.slowtwitch.com/Products/Thin ... _3748.html
    I'm still tempted to get a set, I think they'll just fit my Canyon CF SL.

    Something like 25mm Conti GP4000S should be somewhere in between your two measurements.
  • secretsam
    secretsam Posts: 5,120
    jotko wrote:
    Dunno what Cinelli you have but I am running 25mm Rubino Pros on open pro rims on my Cinelli Saetta with no issues. No way 28s would fit, but 25s are fine.
    It's a Saetta Sprint. Could you pm me some pics?
    It's just a hill. Get over it.
  • DiscoBoy
    DiscoBoy Posts: 905
    Ai_1 wrote:
    Manglier wrote:
    I have just measured up my Michelin Pro 4 Endurance 23 & 25mm tyres. The 23's are 21.5mm from tread to rim and the 25's are 27mm, a difference of 5.5mm. However that's on a Dura Ace C24 rim, perhaps a wider rim will give a lower height.
    25mm Michelin Pro 4 tyres are not really 25mm it would seem. I came across the following review last week when considering picking up a pair. Seems the "25s" are really more like 28s.
    http://www.slowtwitch.com/Products/Thin ... _3748.html
    I'm still tempted to get a set, I think they'll just fit my Canyon CF SL.

    Something like 25mm Conti GP4000S should be somewhere in between your two measurements.


    I had 25s that wouldn't fit, so got the vernier callipers out:

    23MM PRO4 SC WIDTH (mm) (100PSI) 23.44 23.92 23.97 23.74 23.51 23.65 23.76 23.80
    23MM rim+tyre height (mm) 72.00 71.74 71.80 71.98

    25MM PRO4 SC WIDTH (mm) (100PSI) 26.69 26.91 27.22 27.21 26.81
    25MM rim+tyre height (mm) 75.38 75.53 75.54 76.07

    Widths and heights taken at random intervals around the wheel.
    Red bikes are the fastest.
  • ai_1
    ai_1 Posts: 3,060
    Thanks for that data Discoboy
    Any chance you could tell me how much of the ~75mm for the rim+tyre is rim? i.e. how much tyre height is exposed above the brake track?

Categories