Fi'zi:k knows that triathlon shoes play by a different set of rules. Your time can't be wasted on ratcheting buckles, and your feet can't be berated by an ultra-stiff outsole. Basically, triathlon shoes require a system of compromises, yet speed and comfort must still play a vital role. Well, the Fi'zi:k K1 Uomo Shoes have all of these bases covered. With a custom-moldable insole and a stiff, yet compliant, carbon fiber outsole, the K1 checks off all of your boxes for a perfect triathlon shoe.
At the uppers, Fi'zi:k used a material that we don't see in use very often with cycling shoes -- neoprene. We know what you're thinking, how hot is it inside these shoes? The answer? Not hot at all. In fact, aside from the ample perforation and ventilation panels, this material is highly breathable. It was used over the Fi'zi:k-standard, Microtex, for its water-resistance and ease-of-entry with wet feet. So, your transition from sea to land won't be slippery.
To further control slippage, the K1 Uomo has shaped the heel cup at the aft position of the shoe. This feature keeps the foot in the perfect position on hard up-strokes and while climbing out of the saddle. As a result, you're powering the pedals comfortably and efficiently. This has been further heightened by Fi'zi:k's variable stiffness sole construction, called 3D Flex Carbon. The base is comprised of an ultra-stiff carbon fiber plate, with second layer being positioned closer to the heel. This layer is constructed from a material called Tepex that's a little more malleable than the carbon fiber in order to accommodate and support multiple heel and arch sizes. Together, the multiple layers work hand-in-hand with the insole and upper to keep the heel in place and to maximize comfort. And even better for triathletes, the outsole has been design to allow a good deal of lateral flex. So, your feet will experience less fatigue, maximizing your run potential after T2.
And on the subject of the K1's comfort, Fi'zi:k has gone to another level with its 3D Flex Insole design. This insole is heat moldable and fully customizable for the three areas of the foot -- the longitudinal arch, metatarsal button, and the heel cup. To develop this, Fi'zi:k teamed up with Sidas Technologies of France for the design process, and three materials were decided upon. At the metatarsal and longitudinal arches, the insole features the Podiaflex material. Podiaflex was selected for the arch, because its highly moldable properties allow it to perfectly support and conform to your arches. To absorb road vibration and chatter, Fi'zi:k placed Ortholite along the pedal axle portion of the insole. This material is a low-rebound foam and has been cut to the average size of pedal. Having this in place nearly eliminates the numbness generated from long miles clipped-in on the road. Finally, encompassing the heel cup, we the solid and supportive, thermoplastic known as Transflux. Working as a system, we see that the 3D Flex design evenly distributes pressure on the foot, or as Fi'zi:k says, 'the insole is supportive, not corrective or obtrusive.'
For fit, Fi'zi:k incorporated a one-strap closure system, mated with a 'burrito-wrap' upper. What does this mean? Well, the K1 features an opening that runs over nearly the entire top of the shoe. The burrito analogy is drawn from the K1's upper construction where one layer of the upper wraps over the other. This allows you to really dial in the volume of the shoe, whether it be for training or on-the-fly during a race. For your T1 transitions, the two-strap closure system is a breeze. The large top strap opens away from the drivetrain to allow a quick and seamless securing of the shoe. As for the bottom strap, you'll find that this is used less for transitions, and more left alone once you've established your desired volume and fit. However, the gripper tabs placement on the strap simplifies any adjustments that you might need to make from the saddle. To really speed up T1, Sidi has also included a durable pull-tab at the heel.
The Fi'zi:k K1 Uomo Shoes are available in the color Black/neon lime and in whole and half sizes from 40.0 to 48.0.Please go to Fi'zi:k's official website for instructions on how to mold the 3D Flex Insoles.