Shimano has redesigned their C-24 CL composite wheelset for 2013. Bonding carbon to the aluminum alloy rims makes them stronger, faster and more comfortable. Of course, that’s what everyone wants – and this is NOT a perfect world. Nonetheless, Shimano is making some bold claims. Bearing in mind that they’re a conservative bunch whose products are known for durability and reliability, and not too quick to jump on the trendy bandwagon, their claims are worth considering.
There are maybe three things worth considering with this wheelset. On the innovative side, the carbon is structural – not just an aerodynamic shell. This keeps the weight down and makes these a strong contender for climbing. Carbon also does a superb job of soaking up road buzz: which makes these a truly comfortable wheelset. Claimed weight is 1356 grams, actual weight is 1428 grams with the skewers.
Second, Shimano has experimented with rim width. The slightly wider rim widens the contact patch of the tire – which translates into more stable handling at speed. According to them [remember this is a conservative company not known for hype] the combination of width, bladed spokes, stiffness in the hubs, and improved bearings has given the wheel increased mechanical and aero efficiency that translates into less energy needed to keep them spinning. On the other hand, the shorter rim height doesn’t have the aero benefit of a 50mm rim, but neither do you pay a penalty with a cross wind. Yes, there is a compromise: but not one without benefits.
Finally, returning to durability, I have to love the aluminum braking surface. On long descents these rims will not heat up like carbon rims…so there’s a safety factor in play. As I anticipate descending 15 mile long Colorado passes this summer, the possibility of a blow-out from overheated rims at 40 mph is too scary to consider.
Shimano has also rebalanced the spoke tension in the rear wheel and has used stainless steel spokes to take the highest tensions – again, think durability and reliability on long rides. The freewheel body is titanium this year, which offsets the fact that the dura-ace hub shells are not carbon – but continue to be slightly heavier alloy. The flip side? The longevity of carbon hub parts in still an open question.
an endurance tool
These wheels have an ideal spec for endurance riders who like to do a fair bit of climbing. I have not been able to demo them, as yet – but online rider reviews overwhelmingly point to good mechanical and aero efficiency coupled with sublime ride quality. Little things mean a lot on long rides. Not feeling beat-up after riding 100+ miles on questionable roads is the sum of individual component choices that add an edge of comfort. These wheels are my leading contender for that very reason. Reviews an be found here and here.
overcoming the hype
Bike industry marketing strategies include a lot of footage from the pro peloton. And it makes a certain kind of sense: who wants to by things endorsed by people whom you’ve never heard of, and who know absolutely nothing? The down-side is that most cycling consumers are not 135 lb racers who ride 8000 miles a year. A $3000 price difference between bikes will not necessarily add up to a more enjoyable ride. So it is with wheels.
Beyond a certain point paying a lot for a set of wheels has diminishing returns. Consider Ryder Hesjedal, winner of last year’s Giro d’Italia. After riding the better part of 1900 miles he won by a margin of 16 seconds. $3000 wheels for guys like him? I can see that. Beyond the beauty of top engineering, fit and finish – will a rider like yours truly squeeze all the benefit from uber-pricey hoops? Not hardly – but it sure is fun to look!