Tyre pressure for 28mm tyres

MarksMintness
MarksMintness Posts: 484
edited January 2012 in Workshop
Hi guys - quick one: I've just changed my Trek 7.5 hybrid to 28mm Specialized all season tyres which are great.
I'm just curious what pressure I should be inflating them to? I've put 90psi in them but this did feel a bit firm.
Is there a general rule of thumb? I ride exclusively on the road if that helps!
Cheers,
Current bike: 2014 Kinesis Racelight T2 - built by my good self!

Comments

  • 90 PSI
    left the forum March 2023
  • Cheers UFO, that was the pressure I thought it should be initially. Rolls great, just feels firm but that's because it had been at 50psi! Thanks
    Current bike: 2014 Kinesis Racelight T2 - built by my good self!
  • You can even run 80, but I wouldn't go any lower...

    I did Paris Roubaix with 28s at 90 PSI and had no problems
    left the forum March 2023
  • desweller
    desweller Posts: 5,175
    Depends how fat you are, doesn't it.

    Pressure = Force / Area

    Force is the same (your weight).
    - - - - - - - - - -
    On Strava.{/url}
  • huuregeil
    huuregeil Posts: 780
    90 is high IMO, I don't run 25mms that high! Pressure depends a bit on your weight and the tyre itself - the point is to adjust the pressure to suit till you get a decent ride, decent grip, no pinch flats, good rolling resistance. If it feels too firm, it probably is. I'd start at 70-80psi and adjust from there - my 28mm Paselas typically have 70/75 when unladen, and they're quite a supple tyre.
  • Thanks mate,

    I think I'll peg it down to 80 and see how that feels. Might just take the firm edge off the ride.

    Cheers!
    Current bike: 2014 Kinesis Racelight T2 - built by my good self!
  • huuregeil
    huuregeil Posts: 780
    Don't be afraid to go lower either, especially on rough roads. I'm guessing the Specialized runs firm anyway. Experiment, see how it feels and, if you ride with others, use your relative speeds coasting down hills to work out whether you think the rolling resistance is getting high.
  • Diogenes
    Diogenes Posts: 1,628
    huuregeil wrote:
    90 is high IMO, I don't run 25mms that high! Pressure depends a bit on your weight and the tyre itself - the point is to adjust the pressure to suit till you get a decent ride, decent grip, no pinch flats, good rolling resistance. If it feels too firm, it probably is. I'd start at 70-80psi and adjust from there - my 28mm Paselas typically have 70/75 when unladen, and they're quite a supple tyre.

    I ride with my 28mm paselas at 80psi (max recommended on tyre), I am a fairly heavy rider. Check the tyre you are using, it will have a max PSI written on it and I would suggest you do not exceed that.

    D :D