Vision has been an aero company since its inception in 1992 in Seattle, Washington, when it hit the market with aerobars. FSA acquired the brand in 2002. Since then, the sister brands have differentiated themselves with FSA focusing on lightweight and Vision chasing aero gains. Vision is now selling the Metro 40 and Metron 55 carbon wheels that the Cannondale Pro Cycling team raced on last season.
Vision stepped up its work in CFD (computational fluid dyanmics) following a 2009 VeloNews group test of aero wheels in a wind tunnel, and “we didn’t like where we came up,” said FSA marketing manager Mike Lawless.
“Our engineer Ron Correa was left alone for two years to develop the Metron 81 rim,” Lawless said. “What we wanted to do was capitalize on the open patent from Zipp and Hed that made the center of the rim wider than the edge of the rim, which allows crosswinds to hit and bend around the rim without a lot of turbulence.”
“The wheel was developed from 0 to 30 degrees of yaw,” Lawless said. “The average rider is riding from 0 to 30, or more realistically from 5 to 25. The front and the rear of the wheel will work to push pressure to the center of the wheel and stabilize it.”
Metron wheels come in clincher and in tubular versions with black or red/white graphics
The 40 and 55 wheels, so named for their rim heights in millimeters, are similarly shaped. The Metron 40 weighs 1,320g in a $2,299 tubular set and 1,425g in a $2,499 clincher set. The Metron 55 weighs 1,400g in a $2,399 tubular set and 1,595g in a $2,599 clincher set. Weights are claimed and do not include quick releases.
BikeRadar recently tested the Metron 40 clincher and we were impressed with the performance and the price, relative to competitors in its class.
The wheels use what Vision calls the ‘PRA’ system, for preload reduction assembly, which minimizes the sideload on bearings. On each side of the wheel, PRA locking cones clamp down onto the axle. They hold the clamping force from the quick release, instead of transferring that load to the bearings. “Using PRA, we found a 10 percent reduction in drag,” Lawless said. “We call it free speed.”
Locking cones prevent quick-release clamping forces overloading up the bearings, Vision says
The wheels use a 2:1 spoke lacing system, with 14 two-cross spokes on the drive side, and 7 radially laced spokes on the nondrive. The bladed spokes are laced into brass nipples.
All the wheels come in carbon clincher and tubular versions, with black or red graphics.
As is the trend these days, the wheels are optimized for 25mm tires. The external rim width is 25mm; internal width is 17mm.
FSA sales manager Ivan Harms said it was a fight to get Team Cannondale to even try 25mm-wide tires. “The Cannondale guys were freaking out about 25mm tires,” Harms said. “‘No way!’ they would yell, waving their arms around. It took more than half a season to get them to even try it, but by the end they were racing on them and loving them.”
By season’s end, Cannondale had racked up 77 podiums racing on Metrons. Regarding braking performance in wet weather, Lawless noted that Cannondale’s Danielle Ratto won stage 4 of the Vuelta a España as “the only guy on carbon wheels” on a pouring-rain day. Vision recommends use of SwissStop yellow pads with its wheels.
Metron wheels are optimized for 25c tires
There is also a disc-brake tubular version of the Metron 40 that Raleigh-Clement raced in cyclocross this year. There is no PRA system on that set, but Vision is working on that for the future along with carbon clincher disc wheels.
Also expected to hit the market this summer is the Vision Metron 3-Spoke, which Cannondale raced in some time trials.
Metron has a 1,002g disc that is basically a Metron 81 with a shell attached to either side.
Finally, Vision is shipping the 4D handlebar, a $369 240g sculpted carbon bar. The 4D has a slight outward flare in the bend, a flat perch behind the lever-mount area, and an elevated height relative to the stem, thanks to a mountain-style rise. It comes in 40, 42 and 44cm widths.
The 4D handlebar has an upward rise as well as a forward sweep
UK pricing was not immediately available, but will be added to the story above as soon as possible.
via BikeRadar.com http://ift.tt/1hZK74j
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