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by James Huang
August 28, 2017
Photography by James Huang
TECH NEWS BROUGHT TO YOU BY BIKEEXCHANGE
Knit uppers are all the rage in the running shoe world, and the concept has now made its way to the cycling world with the debut of Giro’s new Xnetic Knit technology. Giro will offer the new uppers on three new shoes — the Empire E70 Knit, the Empire VR70 Knit, and the Republic R Knit — all at fairly reasonable price points when they become available later this year.
Currently, most cycling shoe uppers are made in similar fashion: several pieces of synthetic leather and/or mesh are cut from larger pieces of fabric, bonded or stitched together, and then thermoformed in an oven with a last inserted into the shoe to create the final shape. While effective, the process doesn’t always provide as much flexibility as many designers would like, and it also results in a fair bit of wasted material.
In contrast, knit fabrics are basically formed from rolls of string that are woven together — like socks, for example. Multiple colors and even different materials can be interwoven together, the same single piece of knit fabric can have specific material blends in strategic areas, and since the final product is formed in one step and isn’t cut from a larger piece of material, there’s also less waste.
Giro’s new Xnetic Knit material uses a blend of nylon and polyester yarns (Giro wouldn’t disclose the precise blend), which are woven together to form a blank that is then wrapped around a last, heated in an oven, and finally cooled to lock in the final shape. According to Giro, the heating process melts the nylon fibers and fuses them to the polyester yarns to give the knit material some rigidity, while that polyester base lends a softer hand. Strategically placed sections of polyurethane film are then thermally welded either on top or inside, depending on the shoe model, to add more structure.
Giro’s new Xnetic Knit uppers certainly have a distinct aesthetic, but the fabric also has an advantage over traditional synthetic leathers in that the properties can be tuned in specific areas based on the knitting pattern and the material blend.
The process of making synthetic leather uppers produces a fair bit of waste, whereas the knitting process yields pieces that are almost in their final shape straight out of the machine.
Xnetic Knit uppers are made from a secret mix of nylon and polyester yarns, and Giro says it experimented with multiple blends to yield the desired properties.
This early prototype was built with 100% nylon, and was far too stiff and unyielding.
Another prototype was made with only polyester yarn. Although extremely comfortable, it was also wholly lacking in the structure needed in a cycling shoe.
Polyurethane films can be added as needed for additional structure and reinforcement.
In addition to providing a very unique aesthetic, Giro says the Xnetic Knit uppers are also more breathable, more comfortable, and far faster-drying than traditional microfibers. A durable water-repellant coating is applied as well (which also helps keep the shoes clean).
In a refreshing departure from the norm, Giro isn’t debuting its new knit technology as a higher-priced option. In fact, shoes with Xnetic Knit uppers will actually be slightly less expensive than analogous models built with conventional synthetic leathers.
“With the knit, it comes out of the machine like a square sheet of paper; you trim off a little bit of excess, and there’s very little waste in the process,” said Giro creative director Eric Horton. “The shoe is almost complete as the process is finished, and obviously, that gives us some benefits in efficiency and pricing, so we’re able to bring this technology in at a really attractive price point.”
The new Empire E70 Knit features the same Easton EC70 carbon fiber sole and simple lace-up design as the standard Empire; a women’s version with a specific last will be offered as well, and both will carry a retail price of US$200 / AU$TBC / £199 / €229. Claimed weight is 250g for a size 42.5 shoe.
For cyclocross racers and trail riders, there’s the new Empire VR70 Knit, which also uses an Easton EC70 carbon fiber plate, but adds a fully treaded Vibram rubber outsole and additional armoring on the exterior for increased durability and protection, as well as a stretch knit cuff to help seal out dirt and debris. Retail price is US$250 / AU$TBC / £219 / €249. Claimed weight is 380g for a size 42.5 shoe.
Finally, the Republic R Knit is aimed at touring riders and commuters, with its fiber-reinforced nylon plate, lightly treaded outsole (for use with two-bolt cleats), and lighter armoring than the Empire VR70 Knit. Retail price is US$140 / AU$TBC / £139 / €159. Claimed weight is 310g for a size 42.5 shoe.
According to Horton, the company is likely to expand the range of knit footwear offerings in the future, too.
“[Knit] feels completely unique on the foot,” he said. “It doesn’t feel like a synthetic leather shoe and it doesn’t feel like a mesh shoe. We can zonally specify the performance characteristics that we want, and that’s something you couldn’t do with synthetic leather. We’re just getting started with this technology.”
“We have basically unlimited canvas here to tune the aesthetic and the performance of the shoe, to really push footwear in some interesting new directions,” added Giro’s brand development manager, Eric Richter. “This, to me, could really shift the whole footwear category.”
The new Giro Empire E70 Knit will be offered in four men’s colors.
All Giro Empire V70 Knit shoes will feature the same Easton EC70 carbon fiber sole as the standard Empire.
Giro will also offer a women’s-specific version called the Empire W V70 Knit, which features a lower-volume toe box and a narrower fit through the heel.
An off-road variant called the Empire VR70 Knit will be offered in three different colors, all with bonded external polyurethane skeletons and rubber armoring around the toe and heel areas.
The outsole is made from grippy Vibram rubber.
A separate ankle cuff is stitched in, made of a stretchy material to help seal out dirt and debris.
The touring- and adventure-friendly Republic R Knit is attractively priced, and will be available in two different colors.
The Republic plate is made of fiber-reinforced nylon, and its lightly treaded outsole is designed for two-bolt cleats for easier walking.