Wren CAC Rotor Angle w Caption

Metal Matrix materials have been around for decades, but the methods for evenly dispersing fine particles and for machining the material were either nonexistent or prohibitively expensive. ​Wren Sports has partnered with some of the brightest minds in metal matrix materials and in the industrial laser industry to be able to produce the Wren Ceramic-Aluminum Composite rotor.

The Wren Ceramic-Aluminum Composite (CAC) brake rotor is the first true revolution in disc brake rotors for bicycles. ​Compared to stainless steel, the Wren CAC rotor provides improved heat dissipation, improved modulation, superior wet braking, superior wear characteristics and significant weight savings. The Wren CAC rotor is 100% CAC. We do not just add a coating to the brake track. Being 100% CAC allows for greater heat dissipation and lighter weight. The Wren CAC rotor is designed for application to ISO 6 bolt hubs. Only steel or titanium bolts should be used. Wren CAC rotors require using standard organic/resin pads only.

The Wren CAC rotor passed the new ISO braking tests at SGS Labs and passed CPSC testing. One of the new ISO tests calculates the ratio of wet braking to dry braking performance. The ISO standard is >40% (>0.40). In other words, to pass, wet braking must be at least 40% as good as dry braking. The larger the number, the better the braking performance. The SGS Lab test results using the same bicycle and changing only the rotor are:
Front Brake: CAC – 1.01 ~ 1.31, Rear Brake: CAC – 1.60 ~ 1.70
Front Brake: SS – 0.72 ~ 0.86, Rear Brake: SS – 0.89 ~ 1.02

Wren CAC rotor sizes and weights:
​140 mm – 55 grams – Coming soon
160 mm – 63 grams – Available now
180 mm – 74 grams – Available now
​203 mm – 98 grams – Coming soon