Enduro's top-tier XD-15 ceramic-hybrid bearing in the 6805 size, most often fitted as a direct replacement in Shimano external-cup bottom brackets. It runs smoother the more you ride it.

Highlights

• Radial bearing, 25 x 37 x 7mm (ID x OD x width)
• XD-15 races: corrosion-proof, cryogenically treated nitrogen steel
• Grade 5 silicon nitride ceramic balls, maximum size in deep-groove raceways
• Dual-lip labyrinth (LLB) seals with a 90% fill of Kluber NBU52 grease
• Gets smoother with use as the ceramic balls polish the races
• ABEC-5, CN clearance

What makes XD-15 different

XD-15 is Enduro's own ceramic-hybrid recipe. The races are corrosion-proof, cryogenically treated nitrogen steel, paired with Grade 5 silicon nitride ceramic balls in a proprietary process. Deep-groove raceways leave room for the largest possible balls, for more contact area, performance and longevity. Unlike most bearings, XD-15 gets better with use: as it wears in, the super-hard ceramic balls make the races even smoother, so it becomes faster and smoother with time and use.

Where it is used

Enduro says the most common use for this bearing is as a direct replacement in Shimano external-cup bottom brackets when using the plastic Shimano bearing insert. If you would rather not use the plastic insert, Enduro points to its MR 2437 bearing as the correct choice for that application.

Fitting and servicing

Routine servicing isn't needed to keep the XD-15 warranty, but Enduro recommends an annual service by a professional mechanic. Where possible, leave the bearing installed while servicing. If it has to come out, Enduro advises pressing it out gently with a linear press and the hub axle rather than using a blind hole puller. Our Marrickville workshop handles hub, bottom bracket and component bearing replacement; fitting is a separate workshop service and is not included in the price.

Compatibility & fit

• Size: 25 x 37 x 7mm (ID x OD x width)
• Main use: Shimano external-cup bottom brackets with the plastic Shimano bearing insert (per Enduro)
• Without the plastic insert, Enduro specifies its MR 2437 bearing instead
• Match the clearance (C3 or CN) your hub or component maker specifies