This unique custom designed bearing allows you to fit 30mm cranks directly into a BB86/92 frameset. With the limitation of just 41mm inner diameter of the BB86/92 bottom bracket shell, it requires a special solution to accommodate for a 30mm BB spindle. By utilizing flanged double - row bearings that press directly into the BB shell, we are able to maximize contact area by doubling the number of balls per side to provide a long lasting solution in an extremely tight space. These bearings feature 440C stainless steel alloy races and balls with 90% fill, high - pressure, water - proof grease. Not all stainless steel is created equal. Enduro only uses 440C stainless steel balls and races to provide long life and superior corrosion resistance in applications and environments that may be less than ideal. 440C has the highest strength, hardness, and wear resistance of all the standard 440 - series stainless alloys with high carbon content. As expected, it is also the most expensive of the 440 series alloys and requires multiple rounds of heat treatment and cryogenic treatment to achieve its superior mechanical properties. Though stainless steel has 20% less load capacity and is slightly softer than our standard 52100 chromium steel used in most of our bearings, stainless steel is an excellent alternative for use in wet conditions, if you wash your bike often, or where sweat can be a problem. Enduro stainless bearings all carry a full two year anti - corrosion warranty. This bearing is designed specifically for BB86/92 framesets and cranksets with 30mm BB spindles (BB386 and BB30). The Enduro line of bearings are available in high - carbon chromium steel, 440C stainless steel, ceramic - hybrid and XD15 with ceramic or stainless balls. Our bearings are always engineered with deepest groove races possible to accommodate the largest balls and feature dual - lip seals that ride in a micro - groove creating a full labyrinth to provide superior protection against the elements. These Bottom Bracket bearings feature 440C stainless steel alloy races and balls with 90% fill, high - pressure, water - proof grease for maximum corrosion resistance
