Making good great

It took Factor four years and a new factory to improve the Ostro

- Sam Challis

'The instructions I gave our design team when it came to revising the original Ostro basically amounted to "just don't screw it up", says Factor owner Rob Gitelis. 'We wanted to improve aerodynamics but only if we didn't have to do it at the expense of the Ostro's other characteristics, as we were happy with aspects such as stiffness, handling and weight.' If the brand's claims are to be believed (and given how transparent Gitelis and Factor's director of engineering, Graham Shrive, have been about how the bike was developed and validated, it wouldn't seem unreasonable to believe them) it is a case of mission accomplished. Factor says the Ostro 2 saves 0.055 in the bike's coefficient of drag, which is meaningless to most people, so to put it in simple terms the new bike is 10% faster than its predecessor.

Expressed in power, the Ostro 2 is a claimed seven watts more efficient at 45kmh on average across a range of wind angles, and Gitelis says it is more aerodynamically efficient than a Cervélo S5 by 6% and a Specialized Tarmac SL8 by almost 7% over the same yaw sweep. Those companies may wish to dispute those claims, but whichever way you slice it, the new bike is significantly faster than the old one.