Pirelli has launched the new P Zero Race TLR SL-R, a tyre claimed to be up to 15 watts faster than the P Zero Race TLR RS used by Mathieu van der Poel. Using new patented PAAS (Pirelli Advanced Aerodynamic System) tech, this sees a 'spoiler' built onto the lower sidewall of the tyre, which decreases the effective inward depression caused when fitted to a rim. PAAS is the result of a research project in which the interaction between tyre and rim was studied to improve airflow efficiency over the tyre and outer wheel rim. Pirelli says the P Zero Race TLR SL-R is the most aerodynamically efficient tyre in the world across a +/- 20-degree yaw range, without sacrificing rolling resistance or grip. Read more: Best road bike tyres in 2026 13 of our favourite clincher and tubeless tyres Inspired by the P Zero Race TLR RS The new tyre is claimed to save up to 15 watts compared to the P Zero Race TLR RS. Road Bike Connection Spring - Rupert Fowler The P Zero Race TLR SL-R can be thought of as an evolution of the brands P Zero Race TLR RS lightweight race tyre, which until now has been used by its sponsored pros, including Mathieu van der Poel and Mads Pedersen. It uses the same SmartEVO 2 compound, which Pirelli says is based on motorsport-developed polymers, and a 120 TPI (threads-per-inch) carcass construction. Pirelli says this offers high levels of suppleness and grip in both wet and dry conditions. The tyre is also said to maintain aerodynamic performance consistently as it wears and is compatible with wide-profile rims. Pirelli says the new tyre features the same construction as the RS tyre under the skin. Road Bike Connection Spring - Rupert Fowler Pirelli claims the SL-R also improves rolling efficiency compared to the RS, delivering around a 10% reduction in rolling resistance according to its own testing (equating to roughly 2 watts per set). Where pro teams differ is in their usual choice of tyre size. According to Carlo Di Clemente, Pirellis road and gravel product manager, van der Poels Alpecin team will usually opt for a 30mm tyre to better match the teams Shimano wheels, while Pedersens Lidl-Trek teams Bontrager rims are best suited to 28mm tyres. Accordingly, the P Zero Race TLR SL-R is available in both sizes at launch, while a 32mm version is set to follow later in 2026. Pirelli says the 28mm version weighs a claimed 275g, making it the lightest tyre in the current P Zero Race TLR range. Weve weighed our test tyres at 288g apiece, in a 28mm size. The P Zero Race TLR SL-R will be offered in Black-Silver and Black Team Edition colour options, costing 94.99 / $127.90 / 99.90 each. The Team Edition will cost 99.99 in the UK. How does PAAS make the P Zero Race TLR SL-R faster? Pirelli says it has tested prototype tyres ranging from 28-35mm wide. Pirelli The PAAS research project is said to have taken 18 months, incorporating CFD simulations, lab testing, road testing and wind-tunnel validation, with four different wind tunnels used across 10 test sessions. Put simply, PAAS is intended to keep air attached to the tyre and rim for longer across the typical +/- 20-degree range of yaw angles cyclists are exposed to most often. Pirelli says the system is also designed to enhance the so-called 'sailing effect', where aerodynamic lift generated at yaw can contribute a small forward force, reducing overall resistance. In normal circumstances, a typical bike tyre will exhibit a lightbulb effect, whereby the rim grips to the tyre bead and the tyres sidewall expands outwards under pressure. According to Pirelli, this can encourage airflow separation at the tyrerim interface, increasing drag. Pirelli says the SL-R is significantly faster than the existing RS race tyre. Pirelli Alongside this 'standard' tyre profile, Pirelli says it has tested other tyre-profile solutions it has observed from rivals, including a narrow tyre, a pointy tyre and a vortex-generating tyre (such as the Continental Aero 111 front tyre). Pirelli says the PAAS 'geometry construction' optimises the position of the tyres maximum width and smooths the transition between tyre and rim, helping to reduce airflow detachment and therefore drag. This carries a natural small weight penalty given the additional material applied to the tyres sidewall, but Pirelli says this is outweighed by the aerodynamic gains made, especially at racing speeds. The tyre creates a smoother interface with the outer rim wall, but maintains a small gap to aid installation. Pirelli In testing at 45km/h (where Pirelli used a 60mm-deep hooked rim with a 23mm internal width), a 28mm P Zero Race TLR SL-R produced lower drag by 15 watts at certain yaw angles compared to a same-size P Zero Race TLR RS tyre, with smaller but consistent gains compared to other-brand rivals across a broader range of conditions. The brand adds that tyres and the front wheel together can account for up to 5% of total aerodynamic drag, underlining the importance of optimising this interaction. Pirelli says it has applied PAAS to prototype tyres ranging from 28-35mm wide, across a range of contemporary road-racing wheels, and claims PAAS will inform its tyre construction going forward.