Originally Posted by songfta
Two things that'll make your rides even better:
1. Switch to 25mm tires across the board. I was a 23mm rider for years, and switched to 25mm Conti 4000S and Michelin Pro4 Race tires in mid-2012. The difference in ride quality - faster pace, smoother ride, better grip in the corners during races - was marked. For big guys like us, going 25mm is really a no-brainer, and worth it.
2. Lower your tire pressure, as a rule. Sure, pumping 23 or 25mm rubber to the limit seems faster, but it isn't, as your wheels get deflected more by roughness in the road - i.e. your momentum is being shot all over the place, rather than in the direction you wish to go. I ran my 23mm tires at 105-110psi most of the time, and suffered no consequences from the change. On the 25mm tires, the highest I'll go is 105psi - most of the time I'm at 90 or lower. And my front tire is always running lower pressure than the rear (between 5 and 10psi).
Either one - or, preferably, both - of these changes will really bring about positive changes on your rides.
Ride on! :)
Thank you. Interesting...So, I have a few questions here, so I can understand.
Theoretically, less rubber on the road leads to lower rolling friction. How does a wider tire lead to higher pace, all other factors equal (same tire model and pressure)? This isn't questioning your perspective or experiences, btw, I'm just trying to get my head around going with a wider tire, and that resulting in higher speed given the same output. If I'm rolling on a smooth road, wouldn't the narrower tire, run at the same tire pressure, have lower rolling friction and result in a longer runout or higher speed roll given the same output from the rider?
Grip in corners, I definitely understand. Larger contact patch means greater friction = better grip. So dropping pressure gives better purchase on the terrain. I've done a little bit of wheeling, and aired down to increase surface area contact, resulting in better grip (in addition to better absorption, as the lower pressure effectively lowers spring rate).
Also I understand the deflection aspect of lower air pressure in the tires. A parallel can be drawn to race cars. On rougher tracks, smart racers and crews will switch to lower rate springs, so the compliance allows the tires to be in contact with the surface more often, which affords better acceleration from a dead stop, braking and cornering.
With race cars, you typically sacrifice rolling friction for handling and braking in tire compound choices, but it just has to be done. You don't make a turn or a braking zone, and your day will be over quickly.
So what I'm getting at is....my admittedly inexperienced cycling tire brain would lead me to choose a larger contact patch (lower pressures and wider tires) for winding terrain and/or rougher surfaces, and a smaller contact patch (higher pressures and narrower tires) for less winding terrain and smoother surfaces.
In my case, road conditions are generally pretty good here (not a lot of weather, and rarely drops to freezing, so the pavement consistency tends to have longevity). That said, it would seem to me that a balance of smaller contact patch, while tuning comfort with air pressure would be a decent approach.
Is this crazy talk? :) I could be totally wrong here, I'm just trying to apply what I know from my auto racing experiences.
Once I wear out the 23s I'm on, I'm definitely up for trying 25s, and I could expect greater comfort, cornering prowess and even braking....but how could they be faster?
Thanks for sharing your thoughts. It's interesting learning not only about all the new gear, but tires too. Just like in auto racing, they can make one of the largest improvements in performance of any element on the vehicle.