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I just recently bought a new crankset that included the bottom bracket, a english threaded 68 mm bb. I installed the crankset and for some reason its stiff, it moves but doesn't spin at all, all it does is simply move. Do you think maybe that i need to take apart the bb and grease it up less? The crankset came already greased up but i think maybe a bit too much.

Thanks in advance Mark Harrington

  • When you say is does not spin freely, can you rotate the crank with your pinky, if so, how easily and is it smooth, or does it need a lot more force and is it rough? If you give the crank a flick (with no chain), how many rotations (or part of one) before it stops, and is it noisy or quite – mattnz May 24 '17 at 4:02
  • Clarification 0 its a bottom bracket cartridge right? So all you do is thread it in on the Drive side and then mount a retainer ring on the left side? To contrast with a traditional cup and cone bottom bracket setup with visible bearings? – Criggie May 24 '17 at 7:00
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    Does the bottom bracket have internal or external bearings? If external the frame could need to be faced (if not done yet) in order for bearings to be aligned properly. If external, depending on the crank, it's also possible to add too much preload which also can make bearings feel stiff. – Rider_X May 24 '17 at 7:21
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    It is not completely clear what you have. An old-fashioned loose-bearing bottom bracket needs to be assembled, greased, and tensioned by the person installing it on the bike. A standard cartridge unit, on the other hand, is simple to install and reasonably idiot proof. Other schemes (external bearings, etc) are a hair more complicated. Which do you have? – Daniel R Hicks May 24 '17 at 22:02
  • If you take the crank arm off the non-drive side does it spin easily? Could it be that you have the cranks squeezing the bottom bracket too much? – Chris Jun 23 '17 at 22:34
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To start with, it's almost impossible to over grease a BB. It could literally be packed in grease and would work just fine. Too much may slow it down a tiny bit, but really, riding it you wouldn't notice. Grease is simply too viscous to cause a lot of friction. It's much more likely it's over tightened or has damaged bearings. Also, with some cheap sealed bearings there could be a short "wear-in" period during which it may not spin freely, but will act looser over time. Depending on the type of Bottom Bracket, you really could be having any number of smaller problems, but I would start with bearing tension(if it's a loose ball BB), or feel if the bearings themselves spin freely without the crank spindle installed(if it's a sealed system). Or if the spindle spins smoothly(if it's a cartridge like a square taper or Splined), and go from there.

  • Thanks, I'll check the barrings but i'm not sure because it's a 2-piece Solid Crank Construction – Marko Harrington May 31 '17 at 5:45

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