The legacy wheel of the disc brake-compatible Ksyrium Family now gets wider rims and a stepped-up finish for improved ride quality - New
When disc brake technology started to appear on road wheels, it was natural for us to develop a disc-compatible version of our iconic Ksyrium Pro. After all, this do-it all wheel is the best choice for most rides: flat or hilly, training or racing.
The difference with discs
First up we needed to take into account the very different forces at work with a disc brake, and for this we benefited hugely from our long history designing mountain bike disc wheels. The main difference is braking with discs displaces the brake forces from the rim to the hub, moving them further away from the ground. Unlike a wheel with rim brakes, the braking torque is distributed through the hub, spokes and the lower rim before it can reach the ground. So the spoke dimensions and lacing pattern needs to be tuned accordingly.
The braking load is also higher on the front wheel since the center of gravity is transferred to the front of the bike when it’s decelerating. Thus, the front wheel needs to be overbuilt with more spokes (24 instead of 18 or 20) and those spokes need to be crossed on each side of the wheel to make sure the brake torque will be efficiently and evenly distributed. The rear wheel also needs 24 spokes, but since the braking torque is generally lower, we are able to keep the Isopulse lacing (radial lacing on the drive side) to maintain a better balance of the spoke tension, thus greater stability and higher lateral stiffness.
The lower part of the rim is also undergoing higher stress than a rim brake wheel. This stress is about the equivalent of the pedaling torque, so what the rear rim is able to withstand in traction, it can also stand when braking. The front rim however, needs to be redesigned and gets the same dimensions as the rear rim, also benefiting from the asymmetrical design as the disc creates an asymmetry in the wheel dish.
Our unique ISM4D technology (Inter Spoke Milling 4 Dimensions) makes sure the rim weight is kept to a minimum for better agility and reactivity when accelerating or braking. By removing extra material from the rim, where it’s not needed for stiffness or durability, we can save a lot of weight without compromising on strength. At just 1595g, the Ksyrium Pro Disc is the best possible choice for your disc brake-equipped road bike.
Matching Yksion Pro tires
To make sure the extra stopping power makes its way to the ground, Ksyrium Pro Disc comes with our Yksion Pro tires in 25mm. They offer a supple 127 TPI casing, Kevlar beads, a well-balanced rubber compound that offers the best blend of grip and rolling resistance and a weight of only 190grams in 23mm and 205grams in 25mm.
The front wheel comes equipped with the Griplink version with a specific tread pattern to help evacuate water when cornering, to increase confidence and speed in difficult conditions. It also offers a very strong Kevlar puncture protection for added safety. The rear wheel comes with the Powerlink version which sports a more supple nylon puncture protection instead of the Kevlar one to lower rolling resistance. And to reduce rolling resistance even further, the tread pattern is optimized to reduce the pressure on the ground. Water is evacuated efficiently through a centre channel to improve traction and efficiency in wet conditions.
The front wheel is compatible with the three existing retention systems. It is delivered ready for 12mm through axle, but can be converted to quick release or 15mm through axle using optional adapters. Thanks to the use of our light, fast engagement Instant Drive 360 hub system, the rear wheel is compatible with 12x142 axle. It can be converted to quick release with optional adapters.
The freewheel is Shimano/Sram compatible and can be converted to Campy or Sram XD-R compatible driver bodies. As for rotor mount, both International 6 Bolts and Center Lock are available.