Xlab Saturn S Wheelsets with Ceramic Titanium Technology (C.T.T) Bearing. A total of 6 ultra low frictions bearing with 42 Solid Ceramic balls rolling on Hard Coated Titanium make these bearing almost friction free. This proven wheel has been given a tremendous speed boost with 4 full Ceramic bearings. Each bearing has solid ceramic balls and titanium hard coated races resulting in up to a 14 minute savings or 4% faster over an Ironman distance race.

     Narrow 19mm Rim Width when time trialing, your front tire should be 19mm to reduce frontal area and improve aerodynamics. For use on the rear where frontal area is less of a concern, 21mm tires also fit great on all Xlab Wheels.

     Optimum 50mm Rim Depth when you add a 19mm tire to the rim, the total aerodynamic length becomes 69mm. At bicycle speeds the ratio (aspect ratio) of rim width to aerodynamic length should be at least 3.0. With a 19mm tire the Xlab wheel ratio is 3.6 and with a 23mm tire the ratio is 3.2. You may see deeper rims on the market; remember that deeper rims mean added weight, more side area to be affected by side winds with minimal increase in speed. Rather than going deeper, Xlab concentrated on the best aerodynamic profile for a bicycle rim, which in Xlab opinion is 50mm.

     Proven Aerodynamic Shape Xlab staff knows what works with aerodynamic and hydrodynamic shapes with winning experience from trans-Atlantic racing yachts, vertical take-off aircraft and multiple Ironman World Championship wins. True aerofoil shapes have a NACA designation. They are clean shapes optimized for the speed the vehicle will be traveling at. You ideally want a continuous smooth gentle change in shape from the maximum thickness to the trailing edge. You want the air to stay laminar. If there are bumps or recesses the air will breakaway and cause turbulence (drag), remember air prefers clean shapes.

     Super Low Surface Friction After taking care of frontal area (only 19mm) and the shape of the aerofoil, the next challenge is reducing surface friction. Xlab has now developed a lightweight high gloss finish for its wheels; greatly reducing friction compared with others wheels. 

     Designed for High Spoke Tension Carbon fiber is a hand laid process and we use high spoke tensions for great lateral stiffness when cornering, so a really solid nipple base is key if you want to avoid constant wheel truing.

     Rider Weight Limit This wheel is designed to have a maximum rider weight of 198 pounds.

     Lacing and Spokes Aero Wheel Lacing Pattern It is essential to use radial lacing on the front wheel because the wheel is fully exposed to the wind and radial lacing reduces aerodynamic drag. For the rear wheel, which carries 55% of your weight, it is essential to have a strong wheel with comfort for the long haul. Consequently Xlab uses spokes two-crossed for more lateral strength and comfort on the rear.

     Wheel Weights front only 575g. Rear 775g. Set 1350g (+ or -) 20g