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It seems like every recent product launch in the cycling world focuses on one word, comfort. More and more everything from bikes to wheels to tires is all about keeping the rider comfortable first. The idea is that no one is all that fast when contorted and uncomfortable.
Of course that seems obvious when you say it, or read it in this case, but it’s not always been something the cycling world takes into account. Road cycling in particular has a reputation for the glorification of suffering and, in the past, fast meant uncomfortable. That’s shifting though, and there’s momentum building as time goes on. New products recognize that it takes energy to be uncomfortable and when a brand can mitigate that, we can ride faster.
Shoes are just one of those categories focusing on comfort now and every new shoe launch seems to also mention a wider last. Among those launches, Trek released the RSL Knit shoe in February. The Trek RSL Knit is a shoe that stands out even in a sea of shoe launches and I’ve been lucky enough to spend time in them since launch.
At first that meant a lot of rainy days riding and racing on Zwift and TrainerRoad but as the seasons have shifted, I’ve also had a chance to spend considerable outdoor miles in them. With that background, I’m ready to discuss the details of the Trek RSL Knit shoe. If you are looking for a new pair of road shoes, Trek might have the right option for you but there are things to consider.
Quick hits: Six things to know about the Trek RSL Knit shoes
- Insoles use a bio based foam made with Rise by BLOOM
- OCLV carbon sole is a 14 out of 14 on the Trek scale
- The Trek RSL, launched alongside the Knit version, uses the same base
- BOA Li2 dials mount to a non-stretch material covering a knit upper
- The knit upper allows your foot to swell without pain
- The new Trek Pro Last is wider than before
- Check out Trek.com for more info
Trek RSL Knit Details
In February of this year, Trek launched a trio of shoes and the Trek RSL Knit was among them. The stated goal of all the shoes was to update a four year old design which sold under the Bontrager name. The update wasn’t just in name alone though.
It started from the base with a new last designed to fit a wider range of real world foot shapes. Mostly that means wider with a stubbier toe box and it’s something other brands are also doing. Specialized is the most notable in that group but Trek adds a secondary technology called MetNet into the mix to further enhance fit.
MetNet means different things in different shoes but the basic idea is to create a low structure area around the first and fifth metatarsal. In the Trek RSL shoe that looks like a series of punched out three-pointed shapes that create stretch in a material that doesn’t stretch. The RSL Knit version takes things in a totally different direction.
Instead of using an upper without stretch, the RSL Knit has an upper closer to a sock than a shoe. There’s no opening down the center and no structure of any kind. From the back of the arch all the way to the toe you’ll find a thick knit fabric in either white or black.
Actually, it’s not totally fair to say there’s no structure. There’s no traditional shoe structure but Trek uses a sophisticated pattern of varying knit patterns to change the way the upper stretches. At the top, where a traditional tongue would be, there’s a tight knit with very little stretch and that spreads along the top before giving way to two different knit patterns below it. In the center of the shoe you first encounter a pattern that allows lots of stretch vertically but not horizontally then a wide open pattern that offers the lowest structure. The low-structure pattern is also what Trek uses in the MetNet areas of the RSL Knit. Among all this low structure knitting there’s a second layer at play as well.
The second layer of the Trek RSL knit is what actually creates the shoe. At the front of the toe you’ll find a bit of hard plastic that protects against toe rub. That’s not the interesting part though. Instead you’ll find the unique secondary structure first shows up surrounding the all-important first and fifth metatarsal. Instead of allowing expansion, the RSL Knit merely surrounds the area with narrow strips of non-stretch synthetic suede. The MetNet area remains wide open in the layer below but the suede forms a triangular structure on the outside of the foot where a BOA Li2 dial mounts at the peak.
The BOA Li2 dial is important in its own right as it’s the best dial that BOA manufacturers. It occupies that slot because it’s got the most granular adjustment in both directions plus it’s pop-to-release. More recently we’ve also seen it occasionally show up in high-end shoes with a metal dial and in this instance Trek offers either silver in the white shoe or gold in the black shoe. Also somewhat unique to the Trek shoe is that instead of a cable, the brand is using the more forgiving fabric rope attachment along with, again, more forgiving fabric loops where it anchors on the other side.
The Trek RSL Knit is a two BOA dial shoe and the second one has a different set of anchoring straps farther up the shoe. Instead of a semi triangle and a kind of half oval anchoring to either side of the carbon base, the upper uses something more like a rectangle to tie into not only the base but also the heel cup.
Unlike the rest of the shoe, the heel cup is a structured and mostly rigid design. The previous Bontrager XXX, as well as the current Trek RSL and a variety of other brands, use a hard plastic shell in this location. The RSL Knit isn’t quite that stiff but it does hold its own and stands up. On the white shoe it’s also a contrasting light gray and on both colors the interior is a shark skin (or cat tongue if you prefer) style fabric that your sock will slide into but struggles to slide out of.
Underpinning all of this is a carbon base that Trek deems the stiffest the brand makes. Again similar to Specialized, there is a central area with steps and an edge that runs along the sides. This creates a stiffer sole and it also helps limit pooling of the epoxy and, by extension, keeps the weight down. At either end of the carbon is a non-replaceable traction pad and there’s a pair of vents both in the forefront and mid foot. What’s perhaps the most unusual feature of the RSL Knit base is that it’s painted either silver or gold depending on the color of the upper.
Also underpinning your foot, is the insole. It’s not something I spent a lot of time with, as discussed below, but it is worth mentioning because Trek has gone above and beyond to try and add some sustainability with the included insole. Both the RSL Knit and standard RSL come with a new insole design using Rise by Bloom instead of traditional foam. What’s different is that while typically an insole would use petroleum based foam, the Rise system instead harvests freshwater algae overgrowth. The harvested biomass is then combined with bio-based additives to create a foam replacement. The process removes an unwanted material from lake shores, thereby sequestering CO2, and returns filtered water.
Trek RSL Knit in use
As a tech reviewer, I’ve definitely explored more shoes than most. There are times I leave my house with a different pair of shoes for each of the five rides I typically do in a week. Over the years what I’ve found is that the first thing I must have is the ability for my foot to swell and remain comfortable.
I don’t have an especially wide foot. In fact, I’d say it’s rather narrow. On short rides, up to maybe four hours, I can be totally comfortable in super narrow shoes like the Giro Empire. After that though, things get more difficult. Those same Giro shoes started to hurt so bad after somewhere around 11-hours that I had to take them off and walk for a few minutes.
The Trek RSL Knit completely changes the game when it comes to long rides and swelling feet and it’s due to a dual nature. On one hand, the amount of compression and support they still have is quite impressive. If I tighten down that front BOA dial my foot doesn’t move even a little. It will also restrict swelling enough that I’ll start to get pins and needles and pain. What’s unique is that when that happens, all I have to do is turn the BOA dial a couple of clicks.
Any BOA shoe allows that to some extent but the RSL Knit is different. Typically the front BOA isn’t doing a whole lot. You can loosen it or tighten it and it won’t drastically change the feel of the shoe as long as you leave the upper adjustment alone. With the RSL Knit the front BOA has the ability to completely change the fit of the shoe. If I want a cranked down and highly compressive fit, it’s there. At the same time, you can also loosen it up for a fit more like a slipper. While there are other shoes with a highly locked in fit, and other shoes that fit like a slipper, there are few that offer both.
Perhaps as interesting as that dual nature is the way your foot stays connected to the base no matter how you have the shoes adjusted. The knit sock-like upper has enough soft compression on its own that your foot will never slide around. Everything comes together leaving you with a shoe that allows both an ultra-tight fit and loose fit but, no matter the adjustment, your foot never slides in the shoe. It’s a unique combination.
Adding to that feeling is something I adjusted based on my own needs. As I mentioned above, I didn’t spend a lot of time with the included insole. Over the years I’ve learned not only do I have to manage swelling but I’ve got low volume feet with collapsed arches and I do best with an insole. Trek does offer BioDynamic insoles to address that need, and they now use 70% recycled material, but I ended up reaching for the Elastic Interface WattD200. I’ve found it does a great job sucking up the volume in a shoe but I also love how soft it is. In this case it’s a perfect match to the supported and almost hugged feeling the Trek upper provides. It’s also specifically designed for ultra-distance riding so it happens to be a perfect match for me in a number of ways. Keep an eye on it for future availability.
Conclusion
The truth is I could rave all day about how much I love the Trek RSL Knit. There’s only a handful of shoes I can think of that work as well for me. The Nimbl Feat ultimate is just as wide and comfortable and the low structure design of the Fizik Vento Powerstrap R2 Aeroweave is a favorite as well. The shoe I’m reminded of the most though is the Specialized S-Works Ares. Both the Ares and the RSL Knit do an incredibly good job of keeping your foot in place while also allowing room for swelling. The only reason I find myself not reaching for the Ares as much is that I’m less in love with the big S-Works text across it. That said, the Specialized does do one thing better.
The Ares is a slightly different shoe and you can feel it. That shoe is specifically designed with the needs of a sprinter in mind and there’s more pressure than the Trek RSL Knit. Despite that, I still wish the RSL Knit was as indestructible as the Ares.
Anyone who wears a white shoe has to know what they are buying into. You have to be ready to be at least a little neurotic to keep it clean. Unfortunately the RSL Knit is another level beyond that. You can’t wash it because of all the suede and there’s no possibility of getting even minor spots out of the knit upper.
When I asked, Trek recommended a toothbrush. If that worked I’d probably say that was the cost of doing business. It doesn’t work though. I went through a wet spot on the tarmac the first outdoor ride and now my shoes have spots. Not a puddle, just wet pavement. There’s also spots from the sealant when I got a flat and if you think a normal carbon base shows marks, try a painted one. I wish I’d chosen black but I also wish there was a black and silver option.
The price probably also has to come into the discussion here. The Trek RSL Knit is one of the best shoes I’ve ever used so I’m not surprised it’s expensive. The only problem is that it brings the inability to keep them looking nice right to the center. This is not a shoe you want looking bad after a single season.
For now, the Trek RSL Knit is going to keep being my go to shoe because of the comfort and performance. I just wonder how long before they look so trashed I find myself reaching for a different shoe? Hopefully before then I find a way to clean them.
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