With so much on the line at Kona in 2008, what could convince top pro triathletes to use any equipment that they hadn’t raced on before? For Belinda Granger, Jo Lawn, and T.J. Tollakson, the answer was 9 seconds over 40 kilometers. Zipp's VumaChrono is simply that much faster than other aero cranksets. Compared to traditional cranksets, the savings can exceed 25 seconds.
To create its distinctive monocoque dome and airfoil arms, manufacturing each VumaChrono requires over 100 steps and takes an experienced worker almost half a day. The breakthrough shape and a massive 30mm aluminum spindle make the VumaChrono by far the stiffest crankset we’ve ever tested while keeping its assembled weight to just 860g including the bottom bracket (172.5mm, 53/39).
The VumaChrono has a unique, spider-less design with outer chainring held in place by 9 screws around the perimeter of the carbon face. The inner chainring has its own set of bolts, making the VumaChrono the first crank intended to accommodate both single and double chainring setups.
The VumaChrono has an ultra-narrow 146mm Q-factor. It includes a bottom bracket with our grade 3 ceramic bearings along with an installation tool made by Pedro’s. A spacer kit is available for compatibility with the BB30 bottom bracket standard.
Because time trialists and triathletes require such a high degree of personalization from their equipment, the VumaChrono is available in 6 lengths from 167.5mm to 180mm and three chainring combinations: 53/39, 54/42, or 55/42.
Caution – the new Shimano 7900 chain requires extra care and finesse to work properly with VumaQuad chain rings. We recommend you use the 7800 chain as this will improve shifting and performance.
NOTE: The 7900 chain does not appear to use a standard 1/2" pitch as all previous road chains and will therefore show irregularities in shifting performance with all 1/2" pitch chain rings including Zipp rings as well as other Shimano rings.
