Truvativ are waving a new bottom bracket around at Interbike. The Gigapipe bottom bracket is claimed to be 16% stiffer than last year’s. The bigger axle retains the ISIS Drive splined interface system, so users of the new BB won’t need new cranks too. Truvativ reckon that square-taper BBs are a thing of the past for high-performance bikes. User opinions on the matter seem to be mixed – the world seems to be divided into people who never have trouble with bottom bracket/crank interfaces and those who regularly do, regardless of the interface in question.
Still, with the ISIS Drive people and Shimano both pushing their own species of spline, the gradual disappearance of square tapers is pretty much a given.
And there’s more BB development on the horizon. Going a step beyond the Gigapipe, the ISIS Drive consortium (Truvativ, Race Face and Chris King) are working on an entirely new BB standard. Like the onepointfive headset standard, the new proposal will call for a bigger bottom bracket shell (probably 48 or 50mm diameter) to allow bigger bearings and an even larger axle.
Rumour has it that discussions are taking place at Interbike between the ISIS people and frame makers to hammer out a standard. Prototype parts exist, but we wouldn’t expect to see anything in production for a number of months yet.
As if all that wasn’t enough, FSA have an entirely different oversize BB standard. Their Megatech system (see www.oversizebb.com uses a larger, threadless BB shell with press-fit bearings. The splines stick to the ISIS standard. Whether the two systems will be merged into one remains to be seen…