UTFS is only actually useful if there is an existing debate! Lot's of what tyre threads, but no real comment on 23 vs 25 that I could see!
Rolling resistance isn't to do with rubber in contact with the road, it's to do with casing deformation. Which is linked to contact patch size and pressure, in that a bigger contact patch (more rubber) actually leads to lower rolling resistance given the same pressure. In practice, the same tyre in 25mm will roll quicker than it's 23mm counterpart at an appropriate pressure. That's for a perfectly smooth road. If the road's rougher, then it swings more in favour of the 25mm.
Aerodynamics, for sure! But clearly only a meaningful effect at higher speeds. Point is, for us mortals, the aero disadvantage of a 25mm compared to 23mm is not worth worrying about.
UTFS is only actually useful if there is an existing debate! Lot's of what tyre threads, but no real comment on 23 vs 25 that I could see!
Rolling resistance isn't to do with rubber in contact with the road, it's to do with casing deformation. Which is linked to contact patch size and pressure, in that a bigger contact patch (more rubber) actually leads to lower rolling resistance given the same pressure. In practice, the same tyre in 25mm will roll quicker than it's 23mm counterpart at an appropriate pressure. That's for a perfectly smooth road. If the road's rougher, then it swings more in favour of the 25mm.
Aerodynamics, for sure! But clearly only a meaningful effect at higher speeds. Point is, for us mortals, the aero disadvantage of a 25mm compared to 23mm is not worth worrying about.