LAS VEGAS, Nev. (VN) — Since Steve Hed and Zipp started beating the drum for wider road rims, a number of other wheel manufacturers have followed suit. The idea of a wider road rim is that the airflow over the tire is improved to drop the overall drag of the wheel, and bigger tires with lower rolling resistance and greater cornering grip will fit on them. The wider rim also widens the tire contact patch, reduces incidence of pinch flats, and allows lower air pressure for a smoother ride with lower rolling resistance on clinchers, and it increases the gluing area and tire retention of tubulars.
Paired spokes, wide rims Rolf Prima’s new TDF 60SL wheel has a 23mm-side, 60mm-deep full-carbon tubular rim with an 11mm rim bed radius to precisely fit a 22mm tire. It is available with either 16 spokes front and rear or 12 spokes front and rear. “The UCI won’t allow less than 12 spokes in mass-start races, but with our paired spoking, we can make this a strong wheel with 10 spokes as well,” says senior design engineer Joel Wilson. Rolf Prima’s paired spokes can be run at high tension because the spokes oppose each other, whereas tight spokes with low spoke count would otherwise tend to pull the rim back and forth. Wilson claims that the wider TDF 60SL is faster aerodynamically than their previous 85mm-deep wheel. Budget tubular Rolf Vigor’s new VCX aluminum cyclocross tubular wheel is 22mm wide and 30mm deep and has a broad gluing surface. Senior design engineer Joel Wilson claims that the wheel is also a great choice for an all-around tubular road and ’cross racing wheel, as it is more efficient aerodynamically than its competitors. Rolf Prima also has the new Alpha aluminum clincher, at 23mm wide and 33mm deep, and new tubeless mountain bike wheels in 26- and 29-inch using NoTubes ZTR rims with 24 paired spokes front and rear. Wide for good gluing The Mercury M-Zero carbon rim is 25mm wide, 30mm deep rim with a 12.5mm radius of curvature of the rim bed to fit a 25mm tubular for optimized gluing. Happy scribe Velo columnist Phil Gaimon of the Mercury-sponsored Kenda/5-Hour Energy Pro Cycling Team presented by Geargrinder has been testing prototype versions of the M-Zero wide carbon wheelset and reportedly found it to his liking. No need for carbon-specific brake pads Hed’s Jet 6 and Jet 9 clinchers with C2 aluminum rim caps have dropped weight to the point that they are close to the full-carbon, Zipp Firecrest 58mm-deep, 1557g/pr. 404 clincher and 81mm-deep, 1759g/pr. 808 clincher in weight while having similar depths and 23mm width at the brake track and bulged shape behind it. Yet the price is far lower and the braking surface is aluminum, with its inherent advantages over carbon for braking. A price-point Express Jet is also coming, as is a return to offering Jet aluminum-cap tubulars again (currently, Hed’s only tubulars are full-carbon Stinger wheels). Grease pump Hed’s new cyclocross wheels have Shimano-licensed Centerlock rotor mounting splines for disc brakes while allowing them to be used on rim-brake bikes as well, due to their 130mm spacing, rim brake track, and plastic cover for the splines. A grease hole in the center of the hub shell (covered by a sleeve) allows grease injection after each wet ride, a potential enormous boon for cyclocross riders. If the rider intends to use the grease injection option, for which Hed also offers a fine-tip grease gun, he or she needs to specify the grease system bearings, which have no inboard bearing cover and an outboard cover that allows grease forced outward from the inside to pass through without unseating the seal. Normal spokes Mercury’s M-Zero carbon wheelset has a wide but conventional spoking. The 20 radial front spokes and 24 rear spokes are black, stainless steel, and bladed – nothing high-zoot there, so repair and replacement is simplified. Lightweight The Boulder, CO-made Dash carbon hubs are part of the secret to getting the Mercury M-Zero carbon wheelset below a kilo. It’s currently 920 grams/pair with a 185-pound rider weight limit, although the company intends to bring it under 900 grams with a higher rider weight limit soon.