I'm trying to remove a sealed cartridge BB. I've removed both cranks and the non-drive side (plastic) came out fine. The drive side is stuck solid - I know it's reverse thread on the drive side and I have the correct tool(s).

I only have a basic tripod work stand and I've been whaling on it very hard but it wont budge at all! I'm thinking of longer lever arm with a piece of pipe or something.

Any tips or suggestions would be greatly appreciated.

  • Longer lever/bigger hammer. If you're sure you're turning it the right direction. – Daniel R Hicks Jan 30 '16 at 12:25
  • 1. It's not a forgone conclusion that the threads are reversed, but if you're sure you're sure. 2. You don't want a bike in a stand when you are exerting the types of forces you need. – jqning Jan 30 '16 at 14:42
  • @jqning, yes, Im sure. I'm servicing a fleet of rental bikes, all the same bike, all the same BB's. – MeatIsMurder Jan 30 '16 at 15:47

What's your frame made from? If its carbon, might be time for the LBS. If its steel then start with easing oil for a couple of days followed by a leverage increase using your pipe. The main danger is exerting too much force and stripping threads.

I'm assuming the cartridge is toast which is why you're removing it. If its a beater steel frame, you might get some motion using heat on the outside of the BB, which should enlarge it fractionally, but will adversely affect your paint and any nearby plastics. And it can set fire to the easing oil or grease, so keep a multi-purpose extinguisher or bucket of sand handy.

When you do get it out, remember to grease (if steel) or whatever coating is appropriate for alumninium/carbon.

  • 1
    If the frame is aluminum try soaking the cup with ammonia. While penetrating oils work well on steel, they aren't as effective breaking down the aluminum oxide that forms. You may also find it easier to lay the bike on the floor. I have seen the cup stuck so bad it required a pipe wrench to get enough leverage. – mikes Jan 30 '16 at 12:19
  • Thanks mikes. Frame is Alu. Have never tried ammonia, but willing to give it a go. – MeatIsMurder Jan 30 '16 at 15:49
  • The aluminum has probably fused with the (steel) bottom bracket, if you do ever get it off then it will more than likely have stripped the threads from the frame - this is reparable by reaming out the bottom bracket hole in the frame and inserting a thin steel tube. – Piers Myers Feb 9 '16 at 17:39

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