Michelin has announced that it has expanded its PRO4 Endurance line with a new 28c clincher, at this year’s Interbike show. Aimed at riders who value puncture resistance while riding rough pavement or dirt or even gravel roads, the PRO4 Endurance boasts category-leading protection.
Michelin claimed its tyre was found to be 40 percent better than an unnamed ‘closest competitor’ at puncture protection in tests done by Finnish company Wheel Energy.
Michelin uses three 110tpi layers in its casing, with an HD Protection anti-puncture layer that runs the full width of the tyre, from bead to bead. Most clinchers use a puncture-protection layer of some sort, but that usually is only under the tread, not the sidewalls as well. The trick for tyre makers is to balance the suppleness of a tyre with durability. With the PRO4 Endurance, Michelin went all in with durability, claiming that flat-protection is the most important issue for most riders.
At Interbike, a group of about 10 journalists did a 15-mile test ride on gravel roads, with most everyone’s tyres set to 6 bar / 87psi. No one flatted.
The PRO4 Endurance also has bi-compound tread design with softer shoulders for cornering and a harder center for durability. In developing the PRO4 line — which also includes the Service Course, Comp, Grip and Tubular — Michelin created a three-wheeled bike to test tyre grip at an angle on wet roads. The test bike looks like a normal bike with a single, large training wheel, but cocked over to the side at an angle between 20 and 40 degrees. Being electric, the test bike let engineers set constants of speed and lean angle to test different rubber compounds, tyre pressures and other variables. Michelin has patented the test bike.
Michelin doesn’t yet have a claimed weight for the 28c version, but the 23c PRO4 Endurance weighs 225g and the 25c comes in at 245g.