Road tires have gotten wider without getting faster, and that's the problem the Protocol RCR sets out to solve. Silca's first road tire treats the modern wide-tire trend as an engineering opportunity rather than an excuse to add rubber, building the RCR around lower-pressure dynamics from the bead outward.

Instead of scaling up an old design and calling the extra weight durability, this one leans on air volume to do the impact absorption, so the heavy puncture layers come off and the casing stays supple.

The casing is a 120 TPI Race Casing architecture developed specifically around the pressures wide rims actually run, which is what keeps the tire holding its shape and ride quality instead of squirming when you drop pressure. The rubber is Silca's Pulsar compound, a rubber-and-silica race blend built to hold rolling efficiency, grip, and durability in balance rather than trading one for another. Flat protection comes from a Ghost Shield layer that's tuned to add security without dragging down rolling speed. It's a slick-profile tire with a cut-in tread pattern, aimed squarely at pavement, chip seal, and the kind of rough race surfaces you'd meet at Paris-Roubaix.

The width range is the interesting part. The 29mm is the smallest tire that still meets modern ETRTO recommendations for a 25mm internal rim width, so it's the pick if you want the sleekest option that plays nicely with today's wide hookless rims. The 38mm sits at the other end, designed for maximum air volume within UCI regulation limits, which makes it the choice for endurance and all-road riding where compliance over rough surfaces matters. The 34mm splits the difference for riders who want volume without going all the way to the widest option. Whichever you pick, all three widths are measured on a 25mm internal rim after 24 hours, so the listed sizes reflect what you'll actually be running.... Read More