Mad Fiber is a Seattle-based company founded on the concept of advancing wheel technology. To do that they built a team around company president Ric Hjertberg, the founder of Wheelsmith and former technology manager at Full Speed Ahead. Chief technology officer, Max Krismarton, an aerospace composite engineer, and Russ Riggins, the CFO, make up the rest of the team. Mad Fiber first showed their wheels at the 2010 Amgen Tour of California, but the development process dates back to 2008. The goal of the first Mad Fiber project was to develop a wheelset that took advantage of the properties of carbon fiber. Unique to Mad Fiber is that all manufacturing takes place in their Seattle facility.
Mad Fiber tubular rims are built from three distinct pieces: two sidewalls and the tire seat. This is different than other carbon wheel manufacturing systems that use bladders and molds to emulate an extruded metal rim. This three-piece design increases control of the manufacturing process, minimizing voids and eliminating the use of excess resin resulting in increased strength and decreased weight. The hubs are carbon fiber shells with bonded flanges, while the rear cassette body is titanium (White Industries) for light weight and durability. The cassette body uses a unique cone shaped interface that is bonded to a similar convex carbon structure inside the hub to resist pedaling torque. Hub stiffness is further increased on the drive side with an oversized flange to provide a large interface for the spokes. The front rim features at 60mm deep profile, while the rear measures out at 66mm.
Understanding that carbon has different properties than steel or aluminum, Mad Fiber focused on how the spoke interfaced with the rim. The Mad Fiber wheels use 12 spokes in the front and 18 in the rear. Instead of drilling a hole that could weaken the rim, Mad Fiber bonded wide carbon spokes to both the rim walls and the flanges. This design has four main benefits over conventional wheels. First, it eliminates holes and structural stress points. Second, it spreads tension loads over a wider area. Third, it increases strength due to the larger spoke/rim interface, and fourth, it reduces weight by eliminating hardware.
This design does away with the conventional spoke that uses tension to provide a solid link between the rim and hub. To tension the wheel Mad Fiber developed a process of bonding the carbon spokes to the rim walls and hub flanges prior to the flanges being attached to the hub. This is done so that the spoke lengths measure the distance from the rim to the center of the hub before being attached to the hubs. Then when the flanges are bonded to the hub, they are pulled to the outer edges of the hub shell, increasing the spoke distance and creating tension as the spokes are pulled into a position that requires them to cover a greater distance. Mad Fiber wheels tip the scales at 1,085 grams for the set.
On the road, the Mad Fibers are light and responsive while giving the bike an entirely new set of ride characteristics. Without doing a side-to-side comparison in a wind tunnel it is impossible for us to directly compare the aerodynamics of the Mad Fibers against other deep-section wheels on the market. Without being able to provide exact numbers we can tell you that Mad Fiber wheels are fast. Our Mad Fibers came wrapped in TUFO S3 Lite tubular tires.
The wheels climb incredibly well. One reason is their low weight. Another reason is that the rim design of the Mad Fiber wheels is the lightest known in production. The low rotating weight translates into quick acceleration and a snappy feel when climbing out the saddle. Out-of-the-saddle efforts do generate a degree of flex from the wheels, but it does not come across as a hindrance. Much like the feeling of a steel frame winding up, the Mad Fibers give the sensation of moving with the rider’s power rather than against it. In the saddle, the Mad Fibers keep their speed, even at lower speed—and the steeper the pitch the better the Mad Fibers climbed.
Descending on the Mad Fibers was a mix of deep-section speed with the responsiveness and give of a conventional box-section wheel. The wheels are not as stiff laterally as many deep-section wheels, giving the Mad Fibers a bit of give that smoothed out rough roads and allowed the wheels to track calmly through open corners. In tight corners, the lateral flex becomes more noticeable and the bike becomes less adept to quick line changes. A technique of counter steering and smooth transitions is best for getting the most out of the wheels when the road gets twisty.
When the speed really picks up on descents the Mad Fibers are at a disadvantage. The lack of rotating mass reduces the stabilizing effect created by rotating inertia. Combined with the aerodynamics of the rim and the wide-bladed spokes, the Mad Fibers move off line quite easily with the slightest input from the handlebars being amplified. To counteract the Mad Fiber’s handling characteristics it is best to stay relaxed, and keep weight on the front wheel during fast descents.
On flat roads the Mad Fibers roll quickly and maintain speed well up to about 27-30 miles per hour. Over these speeds the Mad Fibers struggle to maintain their speed compared to other deep section wheels on the market. Much of this has to do with the wheel’s overall light weight, and in particular the ultra lightweight rim. The principle that an object in motion tends to stay in motion comes into play here and the less mass an object has in motion the faster it will slow down. In crosswinds the Mad Fibers remained stable and displayed no unusual handling characteristics.
The Mad Fiber rider is a breakaway artist or climber looking for a deep-section aero wheelset without sacrificing their advantage on the hills. A Mad Fiber rider is looking for light weight and speed in a unique and technologically advanced package. Riders choosing the Mad Fibers are not sprinters or hard charging criterium racers, rather they are road riders who churn out a steady 25 mph regardless of terrain. Mad Fiber set out to develop a wheel that took advantage of the prosperities of carbon fiber, and in doing so developed one of the best overall wheelsets available.
Price: $2,899; $3,099 (with ceramic bearings)
Weight: 1,085 grams (pair)