By Matt Pacocha
If Mavic sold the pro-only version of the R-SYS, which popped up at this year’s Tour, it would have been a winner from the beginning.
The current production R-SYS, while marketed as the French wheelmaker’s top “multi-performance” wheel, should really be slotted into the specialty category of a climbing wheel: aerodynamics were totally ignored in the name of inertia, stiffness and weight. It is, nonetheless, something of a confused product. It’s light, but not unbelievably light and the same goes for its perceived stiffness. It’s stiff, but there are other wheels that rival it.
This new team-only tubular version of the R-SYS that Mavic provides the Saunier Duval-Scott team, however, delivers superbly on the concept of a climbing wheel. It retains the features of the consumer version, but at a much lower weight. The only problem is that it isn’t available to consumers. Mavic made this special pro version into what might just be the ultimate climbing wheel. But how?
Well, first off, according to Mavic, a pair of the pro version weighs in at only 1080 grams. For purposes of comparison, our review of six steel-spoked carbon climbing wheels (VeloNews Issue 14, which is now on newsstands), only one model weighs less than Mavic’s claimed weight for the pro R-SYS. In fact, this new version of the R-SYS is even lighter than Mavic’s Cosmic Carbon Ultimates that we reviewed in issue number 12.
The pro R-SYS combines all of the attributes that make a perfect climbing wheel and ignores the one, aerodynamics, that makes no difference on a steep mountain climb, where even the best climbing pros’ speed rarely tops 15 miles per hour. The problem with the production wheel is that it isn’t quite light enough to compete with the carbon climbing wheels on the market.
This prototype R-SYS looks much like last year’s version, yet incorporates some new features that will be available to consumers in 2009 as the “R-SYS Premium,” including a titanium driveside axle cap for the rear wheel and carbon bearing covers for both front and rear. The problem is that’s all the premium gets, and those upgrades drop only a few grams. The prototype the team is using has lighter hubs and, most importantly, lighter rims. The rim represents where the greatest amount of weight is lost and it represents the most important performance improvement.
The prototype R-SYS utilizes the same type and number of tubular carbon spokes for the front wheel and the same combination of tubular carbon and Zicral spokes in the rear wheel as the consumer model, the prototype rims account for almost all of the 200-gram weight difference between it and the consumer version. Because mass distributed further from the axis of rotation is harder to move, rims are the perfect place to cut weight on a bicycle wheel. As a result, lighter rims offer quicker acceleration and translate into a “lighter feel” on the bike.
The prototype rims appear to have some sort of shot peened or hardened surface and a slightly lower profile, but aside from that it’s quite hard to tell a difference from the current model. Low profile rims, I would argue, are a good choice for a climbing wheel because, usually if you climb, you also descend and the lower rim profile offers a more predictable ride down due to a greater resistance to cross winds, especially those whipping around a high Alpine col.
Finally there’s the issue of braking. If all else is created equal, why ride a carbon wheelset when you can choose alloy and its inherently better brake performance?
After seeing this wheel, I’ll reserve judgment on the R-SYS. While the new R-SYS Premium will mark an improvement, it still lags behind this prototype version.