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By Zack Vestal
If you’re an early adapter and have been aching to try out a tubeless road system, you now have a new option, the Hutchinson RT1 carbon wheelset.
The wheels are Hutchinson-branded, but are made by Corima and are exactly the same as Corima’s Aero + Tubeless wheelset (which is not available in the United States).
Paired with Hutchinson Fusion 2 tires (included), this is a ride-ready road tubeless setup, which brings an aero-profile, low spoke count, and carbon clincher rim into the equation. While the wheels can be used with any tire and tube combination, they are best suited to the use of Fusion 2 tires, set up without tubes.
The Wheels Feature:
• Aerodynamic carbon hubs
• Sealed bearings
• 45mm deep, 22.6mm wide carbon rims
• 18 radially-laced Sapim CX-Ray bladed spokes in the front wheel
• 20 Sapim CX spokes in the rear wheel (3-cross drive, radial non-drive).
The spoke heads are anchored and hidden inside the hub shell, and nipples are external at the rim. This construction style should permit easy replacement in the event of a broken spoke. However, a stripped or rounded spoke nipple could present problems, as the tire bed on the rim is completely sealed, and the only access to the rim interior appears to be the valve hole.
I did not disassemble the hubs, but service appears easy, requiring nothing more than standard cone wrenches to access the bearings.
The WrenchingOut of the box, the Hutchinson RT1s were almost ready to go. Installing cogs was easy: spacers are provided to fit behind the cogset of your choice, for proper spacing (freehub bodies are available for both Shimano and Campagnolo). Hub bearings felt exceptionally smooth, and remained that way for the 5 weeks that I rode.
To run tubeless, the supplied valves must be installed. A small O-ring seals the valve against the rim bed, and a larger O-ring holds the valve in place from the outside of the rim. It’s possibly the easiest tubeless valve installation I’ve performed, in that there are no threaded pieces to secure and the fit is very precise. That being said, I do wonder about the long-term durability of the O-rings and the fact that they are the sole method of securing the valves.
Installing the Fusion 2 tires is possible without tools, but is a little more challenging than mounting an average clincher tire. Most notably, the beads are tight and less flexible than you might expect. When my hands were fresh, it was no problem to get the tires on, but I did use a plastic Pedro’s tire lever to get a tire on when I didn’t have the extra strength in my hands. You have to be careful when using a tire lever so as not to damage the tire bead or the rim, so a plastic lever is your only real choice.
I was able to air up the tires and get the clincher beads to seat against the rims by using a floor pump, but it takes vigorous effort. As with many tubeless set-ups, an air compressor makes the bead-seat process fast and easy, and it’s my preferred method. In the case of the Hutchinson wheels and tires, the fit between tire and rim bed is just tight enough to permit inflation if you are quick with the floor pump. Maximum tire pressure is 120psi.
You have to use the included red Corima carbon-specific pads for optimum braking without damaging the rim. I had no problems installing these in Dura Ace 7800 pad carriers.
The RidingRight out of the shop, I was impressed with the ride of the Hutchinson wheel and tire combination. My experience with road tubeless has been limited, but I noticed an immediate sensation of suppleness and smoothness. The ride, in a word, was fantastic. I ran both 90 and 100psi (I weigh 170 lbs) and at both pressures the wheels seemed to roll exceptionally well, and were remarkably smooth.
These wheels also felt stiff, at least an “8” on a 1-10 scale. Climbing and sprinting, the stiffness is notable. At 300 grams each, the Fusion 2 tires are not particularly light, and at 1600 grams, the wheels are not ultra light. However, the only time I noticed the rotating mass was in acceleration from a stop. Most of the time, the low rolling resistance, aerodynamics, and stiffness were the defining characteristics.
The Fusion 2 tires felt grippy and surefooted in corners. Combined with the stiff wheels, cornering felt very precise. Braking was more than acceptable for carbon rims and carbon-specific pads. I did several long descents and noticed no particular fade or heat issues, but braking became a little grabby for my taste. In general I prefer a little more modulation. After more than a month of riding, the brake track showed no wear.
Hutchinson recommends the use of sealant, specifically Hutchinson Fast’air. I first set these up without sealant, and while they did fine while riding, the tires leaked down up to 30psi overnight. After a shot of Fast’air, the tires held air with no problem.
As an experiment, I tried an ounce or two of Stan’s NoTubes sealant in one tire. It did the job as well, preventing overnight leak down. Hutchinson media and PR rep Steve Boehmke said that the company has had some concern over reports that Stan’s sealant can cause corrosion to a rim or tire. However, Stan’s Pete Kastner said, “Nothing in our sealant would damage carbon fiber, or a tire.” And Boehmke admitted that carbon fiber is relatively inert by comparison to metals, which are more prone to corrosion. Per ounce, Stan’s NoTubes is a more cost-effective sealant.
My overriding impression of this wheelset is quite positive. The ride is fantastic, and with sealant, the Fusion 2 tires should be more flat-resistant than a typical clincher and tube combination. This wheelset would be a great choice for all-around racing, and even seems durable enough to serve as a do-it-all, racing and training wheelset.