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28 vs 25mm

vegas76vegas76 Posts: 231
edited August 2019 in Road general
Apparently there isn't quite enough clearance to run 28mm continental GP 28mms on my Giant TCR so the Giant shop suggested I go for 25mms. Was thinking I'd go for GP5000 Tubeless.

Will I feel a big difference in terms of comfort?

Posts

  • imposter2.0imposter2.0 Posts: 11,382
    How will you tell any difference if you can't run 28s for comparison..?
  • vegas76vegas76 Posts: 231
    I have 28s on at the moment but the clearance is like 1mm and the tyres have scuffed the frame.
  • 28mm GP4000S IIs measure ~31mm wide, I've read the GP5000 are similar to 4 Seasons @ ~29mm wide.
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  • vegas76vegas76 Posts: 231
    28mm GP4000S IIs measure ~31mm wide, I've read the GP5000 are similar to 4 Seasons @ ~29mm wide.

    And depth?
  • FatTedFatTed Posts: 1,205
    I think this article has the relevant measurements

    https://www.bicyclerollingresistance.co ... comparison
  • super_davosuper_davo Posts: 661
    Suggest you look at these two articles:

    https://www.bicyclerollingresistance.co ... i-23-25-28
    https://www.bicyclerollingresistance.co ... comparison

    According to this you lose 3mm in height on 5000 28s vs 4000s alongside similar reductions in width.

    One things for certain... GP4000s are huge vs their quoted size. If you went with GP4000 25s, they are pretty much 28s on other types of tyre.
  • pblakeneypblakeney Posts: 16,740
    I have run both on one of my bikes and have found similar. 1mm clearance works in theory but any grit on the road makes the annoyance factor unbearable.
    Regarding comfort, it is more to do with tyre pressure than the width itself.
    Either get low profile 28s or 25s that you are happy to run at the same pressure.
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • vegas76vegas76 Posts: 231
    Thanks for the replies folks!
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