KCNC just debuted their new Taper Roller Bottom Bracket with outboard roller bearings for use with Shimano Hollowtech II cranks with pinch bolt arms.

The design, which replaces the typical ball bearings with roller bearings, claims to be very smooth and exceptionally durable, lasting twice as long as normal bottom brackets. Various reviews of their roller-bearing ISIS bottom brackets floating around on the interweb seem to back up the durability claims.  Roller bearings are similar in principal to needle bearings, just oriented in a circle instead of a line, and Cannondale’s Lefty forks use needle bearings to create what is arguably one of the smoothest suspension movements anywhere…leading me to believe these bottom brackets are pretty smooth, too.

It weighs in at a respectable 130g, fits 68/73mm BB shells and has the standard 24mm inside diameter. Cost is just £39.99, making them very affordable, too. Via Clee Cycles and BikeBiz.


  1. Aren’t roller bearings less efficient than ball bearings? Not a problem in a headset, or a suspension component whose job is to suck up energy, but doesn’t seem ideal for a drivetrain component.

  2. I asked the Cannondale engineers about this since they use roller bearings in their Lefty forks and they said that drag most likely wouldn’t be an issue, but that roller bearings tend to “squeegee” the grease out to the sides, so keeping them lubricated would be trickier, but that could likely be solved by using oil or a very liquidy grease if I had to guess. Like anything else, it depends on what you’re willing to potentially give up to save grams.

  3. the cone shaped bearings (ie tapered roller) need to be pushed in and adjusted from the outside. The cranks aren’t designed to do this.

  4. I’ve blown three cranksets in the last month. Apparently a 220 lb mo fo like me needs automotive technology to keep a simple kid’s bike on the road. WTF is the problem with grease??? Do me a favor, quit designing bikes for kids and make them durable for a man.

    • My grandson did the same thing . The first BB on a new bike lasted about 45 minuits the second about 30 minuits the third an Odyssey BB set lasted about 1 day . We need to use tapered roller bearings like the front wheel bearings on the front spindle of a car with grease seals and all . Chain tensioners and O ring chain like on motorcycles .

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