3 ms·

> As we all know, stiffer tires (higher pressure) is faster. We're living in interesting times for this "conventional" wisdom! One school of thought argues tha

> As we all know, stiffer tires (higher pressure) is faster. We're living in interesting times for this "conventional" wisdom! One school of thought argues that while there might be a theoretical relationship between high pressure and low rolling resistance, but the real-world effect has been exaggerated by poor testing methodology, which usually involves a circular drum as a substitute for a flat road. And that the benefits of achieving low rolling resistance are offset by the losses due to increased vibration. Of course, this school of thought is largely the product of one man, Jan Heine of Compass Bicycles, but it's interesting to read and consider. Personally, I made the jump from 23mm road tires at 120psi to 48mm slick tires at ~40psi this year, and I have to say, my average speed didn't take a hit at all on the road and am much happier and more comfortable. https://janheine.wordpress.com/2018/05/02/testing-tires-isnt-easy/ https://janheine.wordpress.com/2018/05/02/testing-tires-isnt... https://janheine.wordpress.com/2016/03/09/tire-pressure-take-home/ https://janheine.wordpress.com/2016/03/09/tire-pressure-take...

geoka9 8y ago
Just curious, with the same set of tires, didn't you ever notice how much easier it is biking uphill when you don't neglect to inflate the tires before the ride? I'm not a competitive cyclist, but I'm on a bike every day and I notice it on my bikes (mountain, thick heavy tires and road, slick tires).
- meroje 8y ago
  I do, the difference is "woah this thing powers itself" kind of noticeable. Sure I could get the same average speed on my ride, but at the cost of so much more effort on low pressure tires.
  - Lio 8y ago
    Bicycle Quarterly put forward the idea that higher presure tyres feel faster because they transmit more vibration. Normally we would feel that vibration increasing as we go faster. However,even though they feel faster, they’re actually slower. That extra vibration is coming from vertical deflection that a more supple (lower presure) tyre would allow to stay as forward momentum. Personally I keep “25mm” (GP4Ks always seem to measure closer to 27mm for me) somewhere between 70-80 psi but then I’m the sort of madman that thinks I can feel the difference with latex inner tubes.
- plorkyeran 8y ago
  On my mountain bike it's very noticeable when I'm below 30 psi on a road, but the difference between 30 and 50 is not noticeable in terms of speed (hard cornering does feel a bit different).
- ashtonbaker 8y ago
  Sure. There's an optimal tire pressure for each tire, and the wider the tire, the lower the pressure. The point I was making was that a wide tire at optimal (low) pressure is not significantly slower than a narrow tire at optimal (high) pressure. However, any particular tire can be underinflated relative to its optimum, and become sluggish.

geoka9 8y ago

Just curious, with the same set of tires, didn't you ever notice how much easier it is biking uphill when you don't neglect to inflate the tires before the ride? I'm not a competitive cyclist, but I'm on a bike every day and I notice it on my bikes (mountain, thick heavy tires and road, slick tires).

meroje 8y ago
I do, the difference is "woah this thing powers itself" kind of noticeable. Sure I could get the same average speed on my ride, but at the cost of so much more effort on low pressure tires.
- Lio 8y ago
  Bicycle Quarterly put forward the idea that higher presure tyres feel faster because they transmit more vibration. Normally we would feel that vibration increasing as we go faster. However,even though they feel faster, they’re actually slower. That extra vibration is coming from vertical deflection that a more supple (lower presure) tyre would allow to stay as forward momentum. Personally I keep “25mm” (GP4Ks always seem to measure closer to 27mm for me) somewhere between 70-80 psi but then I’m the sort of madman that thinks I can feel the difference with latex inner tubes.
plorkyeran 8y ago
On my mountain bike it's very noticeable when I'm below 30 psi on a road, but the difference between 30 and 50 is not noticeable in terms of speed (hard cornering does feel a bit different).
ashtonbaker 8y ago
Sure. There's an optimal tire pressure for each tire, and the wider the tire, the lower the pressure. The point I was making was that a wide tire at optimal (low) pressure is not significantly slower than a narrow tire at optimal (high) pressure. However, any particular tire can be underinflated relative to its optimum, and become sluggish.