This press-in bottom bracket is designed for use on road frames with a BB shell inside diameter of 41mm and a width of 86.5mm. Because manufacturing tolerances vary, on many frames no special tools will be necessary to install the cups as they will press in by hand. On frames with a tighter fit, a mechanical means of pressing in the cups may be required. This can either be a dedicated tool for BB86/BB92 applications, or you may improvise with a threaded rod, nuts, and fender washers. A center seal where the two-halves meet provides sealing from the inside of the frame.

Angular contact bearings are a step forward in outboard bottom bracket design. Why? Deep groove radial ball bearing cartridges are not designed to be "adjusted." Any inward or outward pressure on the inner races put them out of alignment with the outer races, forcing the balls to ride up the side of the groove and exerting greater pressure on the races. This results in increased friction and premature wear. Since almost all outboad crank sets exert some inward pressure on the bearings when installed, it only makes sense to use a bearing designed specifically for such loads.

IN PROPERLY ADJUSTED ANGULAR CONTACT (A/C) CARTRIDGE BEARINGS, ALL OF THE BALL BEARINGS ARE ENGAGED AND SPREAD THE FORCE OVER A LARGER SURFACE AREA, DECREASING FRICTION, AND MINIMIZING WEAR. EXCESS PLAY CAN BE ADJUSTED OUT OF THE BOTTOM BRACKET WITHOUT THE USUAL RISK OF SIDE LOADING THE BEARINGS.