>>1247793Pt. 4/4
Pro-riders are using faster-rolling, more comfortable 25mm & 26mm tires. The small increase of weight & aerodynamic drag is more than compensated by improved comfort & road-holding.
Rolling resistance is the measure of how much energy is needed to keep a tyre moving down the road. Velonews measured the rolling-resistance of a number of high-performance tyres & found a whopping 83% difference between the best & worse. That's an extra 55 Watts to maintain 25mph, & that's a difference you can feel.
Disc Brakes
As well as gearing choices, you can now choose whether your bike has mountain bike style disk brakes or traditional rim brakes. Rim brakes are still lighter & more aerodynamic, but the difference isn't much. Disc brakes provide better modulation & power, are less affected by bad weather, & continue working even if you ding a rim.
If you ride year-round, another advantage of discs is that winter road crud won't wear away your rims. A replacement rotor can cost little, & even the most costly is still cheaper than a similar quality rim & wheelbuilding labour.
To get the most from the advantages of disc brakes you want a hydraulic system, but the better hybrid & mechanical systems are still good.
