Road Bike Tire Test: Pirelli P Zero Race TLR SL-R 30

The P Zero Race TLR SL-R is the latest addition to Pirelli's road bike range, and it's made for absolute performance in road races and time-trials. The SL-R isn't simply a lightened version of the popular P Zero Race TLR RS, but a completely new design with new LiteCore casing and an aero-optimized PAAS (Pirelli Advanced Aerodynamic System) structure that creates a seamless transition between the tire and rim.

Ad Buy Pirelli P Zero Race TLR SL-R at Amazon.com

The new LiteCore casing is completely different from Pirelli's SpeedCore casing, which we've become accustomed to over the past 3 years. The LiteCore casing does away with the air-tight layer on the inside of the tire, and it's now a 2-layer under-the-tread, 3-layer sidewall design instead of 3-layer under-the-tread and 2-layer sidewalls. This change helps make the tire more supple and provides a smoother ride quality.

The aerodynamic PAAS sidewalls are also a huge change, providing a nearly smooth sidewall-to-rim transition that we haven't seen before. We've seen other aero tires with an aero tread pattern or designed for a specific tire/wheel combination, but they never solved the tire-to-rim transition. Pirelli's new system should be an improvement regardless of which wheel you use.

Pirelli's tires have never been the lightest, and although the P Zero Race TLR SL-R is a bit lighter than the P Zero Race TLR RS, it's still a bit heavier than the competition. This is the price to pay for the aerodynamic PAAS structure, as the sidewalls are progressively thicker towards the bead, and we estimate this adds 20 to 30 grams of weight to the tire.

Pirelli stuck with their SmartEvo 2 compound, which rolls fast yet remains one of the grippiest on the market. Pirelli could have reduced rolling resistance by another 1 to 2 watts per tire by sacrificing wet grip, but that would have compromised its versatility and made it a pure dry-weather time-trial tire.

The Pirelli P Zero Race TLR SL-R is available in 28-622 and 30-622 sizes, and both are available in either a standard color version (grey logo) or a team edition with a flashy yellow logo. As far as we know, it's just a color difference, and the performance should be the same for both color editions. We've already tested the 28-622 size with standard colors a couple of weeks ago, and today we'll look at the 30-622 mm size to see how it compares to the 28-622 P Zero Race TLR SL-R (read our review) and a range of comparable 30 mm tires.

The 30 mm Pirelli P Zero Race TLR SL-R performs nearly spot on to the 28 mm size (read our review) in the rolling resistance tests. We do see slightly less performance in the tread puncture resistance and wet grip tests, but the differences are so small that they fall within the margin of error of our tests. When solely considering these performance measurements, picking the 28 or 30 mm size would come down to personal preference or the aerodynamic performance of the rim and tire combination.

We did find one measurement that's off on the 30 mm P Zero Race TLR SL-R, and it's something we haven't seen before: the tread width on the 30 mm size is actually smaller than that on the 28 mm size. We're a bit puzzled why the 28 mm size comes with a 33 mm-wide tread, and the 30 mm's tread width is just 30 mm wide; it's almost like Pirelli mixed the requested tread width somewhere between design and manufacturing. We double-checked this measurement, and you can also see it clearly in our pictures of the 28 and 30 mm P Zero Race TLR SL-R.

While we raved about the 28 mm P Zero Race TLR SL-R, we rate the 30 mm size lower due to its limited tread width. The 0.5-point reduction is significant, but we expect the SL-R to be used mostly on wide to extremely wide rims, where tread width becomes more important.

Compare the 28 and 30 mm Pirelli P Zero Race TLR SL-R on our comparison section.