MONTEREY, CA (BRAIN)—FSA wined and dined journalists at Sea Otter, bringing them up to speed on oversize bottom bracket technology, which will hit many 2009 models.
“We’ve been talking about BB30 for a while now, but if I gave you a crankset today you couldn’t find a bike to put it on. But that is all set to change soon,” said Ric Hjertberg, FSA’s new technology manager.
“We don’t need to talk with manufacturers any more as so many of them get the product and are making bikes to use it,” he added.
Hjertberg presented actual product and racers who have ridden the cranks at an afternoon session on Saturday.
In addition to FSA, other companies including SRAM announced BB30-compatible cranksets.
BB30 is an open oversize bottom-bracket standard developed and used by Cannondale, Specialized and others. At the heart of it is a large 30-millimeter bottom bracket axle that allows crank makers to switch to aluminum or carbon fiber to save weight.
The larger axle also boosts stiffness because the axle diameter is greater and the bonding surface between the crankarm and the axle is larger.
The larger axle also means the bearing race diameter is 13 percent larger than traditional bottom brackets, and more race surface extends bearing life.
Pedal width, or Q-Factor, is somewhat fixed by chainstay design. Once a frame designer draws in tire clearance and chainstay dimensions, that sets the limit for how close the pedals can be. One of the unheralded aspects of BB30 is that the greater bonding surface between the bottom bracket axle and the crank arm allows a reduction in width of the cranks at the axle.
“Our BB30-compatible K-Force Light is 14 millimeters narrower than our K-Force for traditional bottom brackets, a big improvement in ankle clearance,” Hjertberg said.
FSA showed eight BB30-compatible cranksets—three road, three mountain bike, one gravity and one BMX version.
—Matt Wiebe
