Testing prototype tires over 12,000 vertical feet on asphalt and dirt

Big cotton casings for Haute Route Rockies stage

Given the opportunity to jump in for a stage of the Mavic Haute Route Rockies, leaving from my hometown of Boulder, I stared at the various test bikes in my garage and opted to go with the closest thing to a personal bike I have — a 2012 Specialized Tarmac. Why? I love how it fits and, as a rim bike, it's pretty light.

With a mix of pavement and gravel, the 89-mile day up to Winter Park seemed as good an excuse as any to test some prototype cotton Specialized Turbo tires. But the forecast of lightning storms over 13,000ft /3,446m Berthoud Pass had me more concerned about what to put on the body than on the bike... 

In Colorado, I ride a lot of dirt roads on a regular road bike. Why not?
In Colorado, I ride a lot of dirt roads on a regular road bike. Why not?

Horse for the Course

  • The course:Stage 2 of the Mavic Haute Route Rockies — 89mi, 12,000ft / 3,660m of elevation gain
  • The horse: 2012 Specialized Tarmac with 2018 Shimano Dura-Ace 9000, Stages 9000 meter, prototype 28mm Specialized Turbo Cotton clinchers 
  • The equipment goals: Light on the way up, fast and safe on the way down

The Mavic Haute Route Rockies tackles hundreds of miles of beautiful roads, paved and otherwise
The Mavic Haute Route Rockies tackles hundreds of miles of beautiful roads, paved and otherwise

Haute, haute, baby

I love Colorado's Haute Route format: everyone starts together. There are ample and well-stocked rest stops,  where riders actually stop and rest because time is only taken on 3-4 segments for each day.

As a heavier rider, I particularly appreciate this format when the day's menu calls for all kinds of up. By that I mean, I can get dropped on the steeps and then rejoin the skinny people at the rest stops and still have someone to ride with for the rest of the day. That is a stark contrast to a normal race, right?

Two years ago I did the Haute Route Rockies test event, riding the whole seven-day course with a small group. It was an enormous treat, riding point to point over some of Colorado's most beautiful passes, both paved and dirt. I was curious to see how 'racy' the actual event would be. 

I had my answer just a few minutes into the day's first timed section, as the fast guys blasted up Sugarloaf and I found myself in a group of four with the lanterne rouge. Seriously, there was a guy in an all-red Lanterne Rouge kit (former pro Christian Heule, the event's designated last-man-on-the-road).

Longtime pro Lyne Bessette was also there, riding in the race leader jersey. And then there was me and my friend Fred Dreier, editor of VeloNews. Leader, lanterne rouge and two journos; what a weird group! This was Haute Route in a nutshell; interesting and random mixes of folks riding together.

I am biased, but the mountains around here put the rad in Colorado
I am biased, but the mountains around here put the rad in Colorado

Before we were done climbing Sugarloaf, Lyne, Christian and Fred dropped me, too. Sweating and gasping, I considering flipping it and coasting back home. Stupid steep climbs.

At the first feed zone, though, I rejoined the front group (they had been standing around eating for a while) and my mood improved.

And then I just rolled away from the group...

So what about those tires? Well, Specialized has three official models of Turbo Cotton clinchers: 24 and 26mm widths with a 32mm tread (when laid flat) and a beefier 28mm 'Hell of the North' model with a wider 40mm tread that doesn't have the slick center like the others.

As part of ongoing rolling-resistance testing, Specialized also made some 28mm clinchers with the narrower, slick-center tread. These are the ones I rode.

Specialized has three Turbo Cottons on the market: 24mm and 26mm with a slick center tread, and a 28mm Hell of the North with a wide file tread. I rode a prototype 28mm Turbo Cotton with a slick tread
Specialized has three Turbo Cottons on the market: 24mm and 26mm with a slick center tread, and a 28mm Hell of the North with a wide file tread. I rode a prototype 28mm Turbo Cotton with a slick tread

Up on Peak to Peak Highway, the road undulates a bit and on one of the steeper descents I coasted up to, and then right on by, the front of the group. By the bottom I was maybe 20 seconds ahead of a group of 20 or so. Was this the tires? Um, no. This was me weighing a whole lot more than the other folks (see above)!

Nonetheless, the tires really do feel great. You can read our older review on Turbo Cottons here, but the summary is that a high-tpi cotton casing with a thin layer of pliable, fast rubber results in a creamy ride. Set at about 90psi (I'm 185lb / 84kg), the 28mm tires feel like racing tubulars. In fact, lab data tells us that they are better.

BikeRadar has used rolling-resistance-testing specialists Wheel Energy for tire tests, and Specialized and other brands also send their tires there for third-party testing. In our recent test, we confirmed what many tire brands will tell you, which is that wider tires (to a point) have lower rolling resistance than narrower ones.

So, for example, we found the 26mm Turbo Cottons to be faster than 24mm Turbo Cottons. And 28mm Zipps to be faster than 25mm, etc. Continuing on that curve, the 28mm prototypes have lower rolling resistance than the 26s.

No hot patch here
No hot patch here

Of course, weight and aero drag increase along with width. So, like everything in cycling, it's a balancing act. I weighed the 28mm prototypes at 240g a piece. Not exactly porkers, these.

The 28mm Hell of the North tires have a bit more rolling resistance than the 28mm prototypes because of the extra tread width for increased sidewall protection and textured center for wet grip.

I've ridden those on the Paris-Roubaix course — without flatting, thank you — and can say they don't feel any slower on smooth pavement than a standard race tire. 

Wheel Energy smooth-drum test: 50kg load, 7-bar, 40kph
ModelTread Watts (lower is faster)
Turbo Cotton 24mm 32mm24.6
Turbo Cotton 26mm32mm21.6
Turbo Cotton 28mm prototype 32mm20.8
Turbo Cotton 28mm Hell of the North40mm23.0

The Hell of the North has a 40mm tread to the prototype's 32mm rubber
The Hell of the North has a 40mm tread to the prototype's 32mm rubber

The knock against the Turbo Cottons is that they are thin. Cotton feels magic. Think about how rattly and noisy an old car is at high speed, then think about a new car with good suspension and noise insulation. Getting on cotton casings is similar. But extremely durable cotton is not.

The last time I did a mixed-media mountain ride my friend Jorge flatted his Turbo Cottons three times. Granted, two of those were from the same thing in one tire he neglected to pull out. But still. 

On the Haute Route stage 2 we did perhaps 15 miles on dirt and loose gravel. I didn't flat. Go figure.     

But chainstay clearance on a 2012 bike is a little tight for a 28mm
But chainstay clearance on a 2012 bike is a little tight for a 28mm

Can I get an amen for good rain clothing?

I hate being cold and I'm scared of lightning. So, when staring at a forecast of rain, sleet and lightning, I loaded up the jersey pockets. Castelli Idro jacket with Gore-Tex Shakedry? Check. Castelli Nano Light bibs and Sportful NoRain knee warmers? Double check. Neoprene gloves, waterproof cap and VeloToze latex booties? Why the heck not?

Full disclosure: I did pause at the weight and bulk of lugging the extra clothing. Then I thought about my weight and bulk, and laughed at myself. I'm getting dropped, regardless; might as well be comfy.

The VeloToze covers are great in that they are thin, light, waterproof and — crucially — they fit snugly around the calf. How many of you have ridden with waterproof booties that end up sopping because water flows down your leg into your socks? A bunch of you, I'd guess. But one big downside is that the latex breathes about as well as a trash bag. So I started the day with the VeloToze rolled up onto my shins, allowing the feet to breath normally, then pulled them down onto my shoes partway through.

VeloToze latex shoe covers keep the rain out... and the sweat in. But the tight seal on the calves is a definite benefit in the rain
VeloToze latex shoe covers keep the rain out... and the sweat in. But the tight seal on the calves is a definite benefit in the rain

As for the weather, our group largely skated. We crested Berthoud just as a sleetstorm rolled in. At the top, I pulled on the Sportful warmers, jacket, hat and gloves. A 12-mile mountain descent on wet roads wasn't a problem. At the bottom, some of my thinner riding companions with less clothing were shivering — for some time after we finished. Many other folks behind got caught in a full-on sleet storm; the organizers halted many of them from descending until the worst of it passed.

The Idro jacket is quite expensive. But like the other jackets made of Shakedry, its compact size is almost as attractive to me as the Gore membrane itself. My one gripe is that the wrists are snug and lack stretch. I've torn one wrist a little, puling it over my hands.   

It's really not about the bike

I saw all kinds of bikes at the Haute Route. Lots of disc bikes. Lots of rim bikes. Some bikes with handlebar bags. Some with deep aero wheels. Some with climbing wheels. I don't believe any of this mattered all that much. The important thing was the event itself: riding with old and new friends over some beautiful and challenging terrain. 

Am I the only one still on rim brakes here?
Am I the only one still on rim brakes here?

The fast guys and gals are going to go fast regardless of what they are riding. The rest of us are going to go our speed, too. I'm a big proponent of finding gear that feels comfortable to you, whether that is a saddle or a gear combination or clothing or, yes, tires. 

The Haute Route events are luxury affairs, in what they deliver and what they cost. If that is out of the cards for you, why not create your own with friends? 

Click or swipe through the gallery above for a closer look at my bike and gear.

Ben Delaney

US Editor-in-Chief
Ben has been writing about bikes since 2000, covering everything from the Tour de France to Asian manufacturing to kids' bikes. The former editor-in-chief of VeloNews, he began racing in college while getting a journalism degree at the University of New Mexico. Based in the cycling-crazed city of Boulder, Colorado, with his wife and two kids, Ben enjoys riding most every day.
  • Discipline: Road (paved or otherwise), cyclocross and sometimes mountain. His tri-curious phase seems to have passed, thankfully
  • Preferred Terrain: Quiet mountain roads leading to places unknown
  • Current Bikes: Scott Foil Team Issue, Specialized S-Works Tarmac, Priority Eight city bike... and a constant rotation of test bikes
  • Dream Bike: A BMC Teammachine SLR01 with disc brakes and clearance for 30mm tires (doesn't yet exist)
  • Beer of Choice: Saison Dupont
  • Location: Boulder, CO, USA

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