Introduction Over the years, the field of road bicycles has been developing and changing, especially road bicycle wheels. On the road, riding wider wheels equate to a faster roll, a more subdued and smoother ride quality, and noticeably improved cornering grip with a more confident feel at the limit. Therefore, we came up with the wider CRX series of road bike rims which internal width is 21mm. They are to ride more comfortably, and more quickly by improving wind-resistant with aerodynamic design. The CRX road bike rims are a series of wide road rims with internal width 21mm, made of the materials of Toray T700+T800 premium carbon fibers. All of these rims are tubeless-compatible. You may use these rims for road, triathlon, cyclocross, dirt, gravel, and adventure riding. Quality is what we have always guaranteed. Rigidity and deflection control are the most important factors in measuring the quality of a road bike rim. Because of the use of better carbon fiber materials, Toray T700+T800, and the latest manufacturing technologies, we are able to control the rigidity and deflection of premium edition road carbon rims within 0.2mm. This is a very high accuracy. The weight of NXT45CRX is only 400g. The profile drawing is as below. The tire size for this model of rim is recommended at 25 ~ 52mm. The tire pressure is recommended at 70 ~ 115psi. Advantage of Wider Wheels Wide rims mean riding lighter, smaller performance tires with cushiony, high air volume and firm surface grip. Rolling resistance is lower with wider tires. Cornering grip is greatly improved. Ride comfort is greatly increased. Aerodynamic Optimized Design Nowadays, aerodynamic performance is one of the key factors considered when racing cyclists purchase new equipment, as the aerodynamic drag is known to be the main source of losses in cycling. The aerodynamic optimization of bicycle wheels can lead to decisive gains in running pace. For all of our CRX carbon rims, they have an optimized cross section. Please also note that choosing an appropriately sized tire for an aerodynamically optimized rim is also crucial to reducing air resistance and increasing riding speed. Tubeless-Compatible Design Lower rolling resistance. By eliminating the inner-tube, the friction between tire and tube is also eliminated, allowing the tire roll, flex, and conform to the road with greater efficiency. Flat less, ride more. Flat tires are a buzz-kill. With a little sealant you can eliminate nearly all flats that would have been caused by an intrusive thorn or piece of debris. Run the Best Pressure. Tubeless means you can run the pressure you want to maximize comfort, traction, and rolling efficiency. Visit our tire pressure page to dial in your best tire pressure. Textured Brake Track