Zero Components were a small British company who produced a range of components in the early-1990s; one of those was a titanium bottom bracket. This unit is very different to other boutique manufacturers at the time…
First of all, the CNC machined aluminium inner sleeve and cups are both tapered where they met, so when the cups are tightened in the frame the tapers at each end meet and lock tight. This system is intended to eliminate the need for lockrings due to the added friction. On the plus side, no debris can enter the bottom bracket from the seat tube. On the down side, the Zero design resulted in a void between the inside edge of the cups and the outer edge of the bearings where water and mud would settle.
While many of Zero’s competitors opted for 2 x 61903 (6903) 17x30x7mm double sealed cartridge bearings, Zero took the plunge with lower profile, but wider, 17x26x10 sealed cartridge bearings from the Swiss bearing manufacturer WIB.
Although the WIB bearings are beautifully made, the smaller bearings were not practical when it came to the rigours of mountain biking and so failure was common. To rub salt into the wounds, replacing the bearings was very difficult due to the tapered ends on the aluminium inner sleeve.
The axle is manufactured from 6Al/4V titanium. It is hollow to keep the eight down and has an uninterrupted 17mm diameter.
Early bottom brackets were supplied with cups requiring a 4-pin tool for installation and removal. As these were difficult to find, and people ended up destroying their cups with a 2-pin tool, Zero started supplying 20-tooth cups so a standard Shimano bottom bracket tool could be used.
Axle: 103, 107, 111, 115, 119, 123, 127mm
Shell: 68 or 73mm
Colour: Black, Blue, Gold, Green, Purple, Red, Silver
Weight: 156g (107mm)