On the road, “Aero Is Everything.” That’s the premise that’s driving product development across all lines at Specialized now, and Mark Cote is leading their effort in working with McLaren to take advantage of that company’s aero expertise.
With that introduction and build up, we were really hoping they were going to say the new Roval Rapide aero wheels were another McLaren collabo, but they were developed in house with Cote and wheels/aero engineer Matt Urquhart. Presenting the 2013 Roval CLX60 and CLX40 carbon clinchers, and the 40 will come in both disc and rim brake versions.
The CLX40 has a 40mm deep rim shape and is designed to be extremely light for quick acceleration, have excellent straight line performance and solid braking. Claimed weight is 1396g for the set, and wheel inertia is said to be very low with an excellent stiffness to weight ratio.
Click on through for an interesting discussion on aerodynamics testing for road wheels, plus tires and one heck of a deal (and wild design!) on carbon 29er wheels…
To allay fears of carbon clincher rims, they worked up a specific carbon and high-temp resin compound and thermal dissipation coating (which is fused in and can’t wear off) and brake pad compound that claims to have a gradual pull with slight ramp in friction at the end. Heat management was a concern, but they wanted a rim that could brake hard and fast, letting the rider come in hot and know they could effectively brake at the end. They test it with a brake load equivalent to dragging your brakes down Mount Washington the entire way, about 17 minutes worth. Their wheels passed without deforming the brake track shape.
Jeremy Thompson, another wheels engineer, says “Everyone’s wheels are the best at one point in a crosswind, but we wanted to build a wheel that was really good at everything in real world conditions.”
They looked at steering torque and stability in a crosswind, something that’s getting a lot of press lately with new wheels from Mavic, Reynolds and others, but Thompson says its tough to compare them because there’s no standard test for it.
To make them stable, Urquhart says they went through about 38 different rim shapes. What they tested -using a bike in a wind tunnel that allowed the front wheel to steer and measure torque- was the amount of force a crosswind puts on the leading edge of the rim and tire and the trailing edge. They tweaked the shape to minimize the difference between the two, which creates a more stable wheel.
The CLX40 Disc version uses Centerlock-compatible hubs and 3x lacing on the brake side. Claimed weights are 1550g for disc and 1390g for non-disc. The CLX40 rim has a 16mm/22mm rim width at the top of the brake track. The CLX40 disc uses the same rim mold as the standard CLX40, but doesn’t get the brake surface treatment.
The CLX60 comes in at 1515g and is basically a taller (60mm) version. Rim width is slightly wider at 17mm inside/23mm outside.
MOUNTAIN BIKE WHEELS
The big news on the dirt is the introduction of the new Control Carbon 29. It brings the lightweight and stiffness of carbon rims down a price peg, to just $1,200. But price is just the beginning…they’re introducing an entirely new rim shape. Or, rather, a very old rim shape.
Back in the day, rims were originally rolled steel and didn’t have bead hooks. With the advent of extruded alloy rims, they could easily put the hook on the rim as insurance against the wild variations in tire manufacturing. With tire tolerances more exact nowadays, Specialized found that they didn’t actually need the hook.
Thompson says no one’s rolled a tire off yet, but they do have a 25psi recommended minimum for all of their carbon rims. The tire bead in compression (ie. when inflated) pops into place, and the Kevlar or carbon beads used in good quality modern tires won’t stretch at all, so it can’t expand to the point where it’ll slip off.
Removing the bead hook was instrumental in letting them bring the cost down. When they have to mold or machine a bead hook, it adds time and cost. Just to test the theory, they machined off the bead hook on the SL models, rode them and it worked. The new wheels still have a DT Swiss hub with star ratchet and alloy freehub body, DT spokes, so the cost savings (about $600 versus the SL) come almost entirely from the new rim. Yes, the design sounds a bit scary, but they say it’ll work with any modern UST, tubeless-ready or standard tire.
Claimed weight is 1580g, about 130g more than the Control SL 29 Carbon, and 100g lighter than the Control 29 alloy. Rim width is 27mm wide outside, 22mm inside. 32 spokes front and rear. End caps are included for any axle standard other than 150mm rear, including Specialized’s 28mm OS front.
That bears repeating: This is a 1580g carbon 29er mountain bike wheelset that’s just $1,200. Yeehaw.
For comparison, the Control Carbon 29 SL rim has a 21mm inner width, and it’ll retain the bead hook for the time being.
There’s more new stuff, but first, an overview: All Roval wheels are hand built and hand tensioned & trued, and each model is purpose built for the intended use. Their carbon rimmed Control SL wheels have won World Cups and the Cape Epic, so they’re both race-worthy and durable. Across the line, all models now get a new one-piece tubeless ready rim strip that snaps into place and can be removed and reused. There’s also a new tubeless valve with removable valve core that’ll come with all wheels.
Another big change is a redesigned rear hub and freehub body. A couple years ago, they redesigned their 142 hubs to make the spoke flanges wider and called it 142+. For 2013, they made the same widening changes to the shell of their 135mm hubs. The hubs are made for them by DT Swiss, and use their Star Ratchet freehub body. This means you can pop in the SRAM XX1 compatible Driver Body to upgrade your drivetrain at any time. Bonus!
The Roval Traverse SL Carbon brings carbon fiber rims to their all-mountain wheel offering. It’s built with 27/32 lacing with 9/15/20 front axle options. Rim is 22mm wide inside. Claimed weight is 1500g for the set (26″ only), about 180g lighter than the alloy version.
TIRES
Next up were tires. The new S-Works Turbo claims to be both super sticky for excellent cornering and have lower rolling resistance. In development, most of the teams are running 22c tubulars, so getting them to try wider tires at lower pressures was the first challenge. The S-Works Turbo is a 700×24, the widest they could go and maintain proper frame clearance.
Their teams are now actually asking for clinchers, and their testing shows that they’re actually faster because clinchers have less sidewall deflection and because less energy is consumed compressing the tire because the total sidewall height tends to be lower than a tubular. Additionally, the clincher’s rim shape tends to add air volume, which allows for a lower air pressure. The result is less power from the rider is used just to move the bike. With a latex tube, the new Turbo S-Works 700×24 claims to have just 21.8 watts (116psi/8bar with load at 40km/h) per wheel of rolling resistance, lower than tires they tested from Continental and Vittoria.
The S-Works Turbo has their new Gripton compound (developed in-house). Where most of Spec’s tires are 80% natural rubber and 20% synthetic, the Gripton formula flip flops that to get better traction and rolling resistance. It sacrifices some lifespan (about 30-35%), but it’s intended as a race only tire. It has a new tread pattern that falls farther down the sidewall, another feature the team requested. With Blackbelt puncture protection, claimed weight is 185g.
Elsewhere on the road, the Espoir budget tubular gets a new 700×25 size in addition to the 23. There’s a new Roubaix Tubeless, their only road tubeless option. There’s also new 28 width Roubaix casing that uses a 25 width tread. The odd sizing match up keeps the nimbleness of a narrow tread but the improved comfort and rolling resistance of a larger casing. This is up from the current 25/23.
Specialized has been using FEA to develop their Adaptive Tread concept, and the tech now comes to the new Purgatory mountain bike tire. It’ll come on the front of all 2013 Stumpjumpers. The new Purgatory is 2.3 wide with a claimed 23% increase in efficiency (ie. reduction in rolling resistance).
The new Purgatory does look similar overall, but there are lots of subtle changes to the knob shapes and positions. It gets all-one-length side knobs with functional siping to provide more biting edges. Single center knob gets a radius at the top edge to improve durability and a harder back edge for better braking. Available in both 26″ and 29″.
Other MTB tires get largely just additional sizes. The Butcher Control adds a 29×2.3 a an all-mountain tire. Ground Control and Renegade also get a 29×2.3, and the Storm mid tire gets a 29×2.0 option in S-Works and Control trim.
Cross tires stay the same, but the did call out the Captain CX tubeless ready model because it doesn’t get enough attention. I didn’t snap a photo, but the tread pattern does look pretty good.