Bib tights occupy a weird middle ground in the cycling wardrobe—you want them warm enough to justify the coverage, but not so insulated that you're overheating on every climb. The Competizione Bib Tights from Castelli thread this needle by building around their Thermoflex fabric, a four-way stretch material that provides wind resistance and thermal retention without the bulk that turns descents into a sweat-lodge situation on the next ascent.
The construction here borrows from Castelli's race-oriented thinking. The Progetto X2 Air seamless chamois uses the same pad found in their warm-weather competition bibs, which means you're not sacrificing comfort on longer rides just because temperatures dropped. The bibs themselves use a mesh upper that reduces weight and improves breathability in the core area where heat tends to accumulate, while the Giro3 leg construction employs three-panel shaping that follows the natural bend of your knee without excess material bunching behind the joint.
Reflective accents handle the visibility question that comes with riding in the low-light conditions typical of cold-weather months. The ankle zips deserve mention—they make getting the tights on and off over shoes significantly less awkward than wrestling with a tight cuff, and they create a cleaner interface with shoe covers if you're layering for truly cold conditions.... Read More
The fit runs in line with Castelli's race-cut philosophy, meaning these aren't relaxed-fit winter cruising tights. They're designed to work with an aggressive riding position and maintain their thermal properties through compression against the skin rather than relying on thick insulation. That approach keeps weight down and pedaling efficiency up, but it does mean sizing matters—if you're between sizes, the stretch has limits before you start compromising the fit through the knee panel.
