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Hollowtech II Bottom Bracket Installation Issues

fallenroguefallenrogue Posts: 2
edited August 2019 in MTB workshop & tech
Hi, so I decided to take off my bottom bracket since I wanted to give it a regrease but when I tried to reinstall it, I found out that it kept slanting and required a lot of force when trying to install the drive side cup so I thought that maybe it was because my bottom bracket being worn so I went and got a new one and guess what; same issue. It keeps slanting and requires more force than I think is required. Whenever I watch installation videos, I see that the mechanic can install it in with his hands with not much force but when I try to do that I cannot, I'm scared of tightening it further because I'm afraid that I will damage the threads on my frame. I've got no idea what to do and I'm kind of lost

Any kind of help would be appreciated; im dying to get on my bike



  • philcubedphilcubed Posts: 260
    If you can't get it in straight, it may be that the previous one was not installed correctly and was cross threaded. I had this on a bike, the original BB was cross threaded, so when I installed a new BB it wouldn't go in straight. I got the BB shell re-threaded by the local bike shop.
  • keef66keef66 Posts: 13,123
    You are screwing the drive side cup in the correct way, ie reverse threaded?

    As above; get the BB threads chased by a bike shop
  • me-109me-109 Posts: 1,363
    Or you have Italian thread frame or BB, so the two are incompatible?
  • AlejandrosdogAlejandrosdog Posts: 1,975
    Just set fire to the whole thing and chuck it off an alp
  • AlejandrosdogAlejandrosdog Posts: 1,975
    Just set fire to the whole thing and chuck it off an alp

    or more helpfully, it sounds like the Bottom bracket threads may have got cross threaded. If theyre not too damaged you can clean them up with the right tools. Most Bike shops should have the kit. If youre lucky someone who works there will be able to use the kit properly.
  • gezebogezebo Posts: 364
    Like above it’s very likely that’s it’s been crossthreaded. You should be able to get it re-tapped and faced for about £20 or £30 depending on where you take it.
  • billycoolbillycool Posts: 833
    Get it to a bike shop. You shouldn't have to force it on.

    Better to be safe.
    "Ride, crash, replace"
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