After watching some videos I'm pretty sure that the BB on my bike is a three piece square taper type.

After a short search I couldn't see any any videos or articles on how to remove a BB which has the 20 groove cups (?) and a lockring.

The bike is Pinarello Lungavita single speed. I bought it second hand and I cannot find any info on what the BB is.

Would you be able to figure out what BB it is and what the locking is for?

  • I'm confused -- it looks pretty standard.
    – Batman
    Dec 29, 2016 at 15:19
  • Yeah, pretty much garden variety. The lockring keeps the cups from turning as you crank. Dec 29, 2016 at 15:26
  • The main question would be what style of crank axle it is -- square or one of several spline variations. Dec 29, 2016 at 15:28
  • I'd guess its an ISIS crank to BB interface. You would need an 8mm hex tool to remove the bolt, then a normal crank puller should fit in the socket. The only trick is to thread the first part of the puller in all the way but not too tight, else it messes with the splines and can cause issues.
    – Criggie
    Jun 1, 2017 at 9:27

1 Answer 1


It's probably a cup and cone bottom bracket with the splined tool interface rather than wrench flats or pin holes. Most recent ones are like this, I believe as a function of what tools now make up the standard arsenal at bike factories. Or it may be a cartridge BB with a lockring, which have existed but aren't common. In either case, you remove it by loosening the lockring and then removing the cups.

  • 4
    I doubt its a cup and cone bottom bracket -- more likely just a cartridge BB with a lockring.
    – Batman
    Dec 29, 2016 at 16:07

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