Bottom Bracket problem

ricktabor1
ricktabor1 Posts: 272
edited May 2011 in Workshop
Hi people,

Just after some advice.


I bought an Octalink BB (68mm) the other day. I fitted it to my bike and as i tightened the non-drive side, the spindles became really stiff to turn - as if the bearings were under to much pressure.

I took the bottom bracket off and remeasured my shell.... it is 68mm. I fitted an old BB (square taper shimano 68mm) to make sure that the threads were ok, and to confirm to me that a 68mm BB was correct. This BB worked fine - the spindles span fine.

Do you think that Octalink BB needs sending back?
Is it possible to tighten the non driveside too much?
Has anyone else had this problem?

This BB is the first one i've bought with a plastic (non-driveside) collar. Is this the problem, cheap stuff?

Any advice would be great.
Got to get up to get down

Comments

  • nicklouse
    nicklouse Posts: 50,673
    is this when fitting the cup or the arm?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ricktabor1
    ricktabor1 Posts: 272
    Sorry Nick, not sure I understand the question. It's when I tighten the non drive side collar on a sealed octalink bottom bracket.
    Got to get up to get down
  • nicklouse
    nicklouse Posts: 50,673
    Ok so before getting to the arm fitting.

    sounds like the BB is being forced to bend. ( it runs fine out of the frame?).

    so runs fine out of the frame.
    fitted but with no non drive side cup fitted it still runs fine?

    cup fitted and it does not.

    am i right so far?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ricktabor1
    ricktabor1 Posts: 272
    Sorry about the delay Nick - yes that's right. Although I must say that out of the frame, it doesn't run quite as free as I think it should - does run though.
    Got to get up to get down
  • nicklouse
    nicklouse Posts: 50,673
    bigger diameter axle and new grease does that.

    it sounds like the BB is not going in straight or is being moved off center at the end of fitting.

    what i would suggest is this back the drive side off so the shoulder is not touching the BB shell face fit and home the non drive side cup then tighten the drive side.

    If you want a permanent fix get the drive side shell faced so that there is not any force put on the BB housing (shimano not frame).
    this misalignment would not have had such results with the old Square taper BB as the shell is a little thicker.

    let us know how it goes.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ricktabor1
    ricktabor1 Posts: 272
    Thanks Nick - I really appreciate the help. I'll keep you posted.
    Got to get up to get down

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