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Newbie! Which bottom bracket?

VizzageVizzage Posts: 32
edited January 2019 in Workshop
Hi people, this is my first post. I have a Specialized Secteur from around 2010 and it creaks l, synchronistically with my right foot near the bottom. I think I need to change the BB. I am assuming it’s a UN55 until I get it out; if so, are there any recommended upgrades?

Cheers!

Posts

  • barongreenbackbarongreenback Posts: 229
    Depends which Secteur you had but I had the same model year and mine wasn't square taper. If it's threaded then you have options to upgrade but this will mean changing your chainset too and possibly having the bottom bracket faced properly so that everything lines up as it should. If it's a like for like replacement, the UN55 is as good as it gets really - was pretty much bombproof on my old Specialized Sirrus hybrid.
  • VizzageVizzage Posts: 32
    Ok useful info, thanks - I will wait before I get anything and see what it is at the weekend. Cheers!
  • VizzageVizzage Posts: 32
    Can you tell from this photo, by the way or do I have to go deeper?

    http://i.imgur.com/enSEB2u.jpg
  • arlowoodarlowood Posts: 2,551
    Vizzage wrote:
    Can you tell from this photo, by the way or do I have to go deeper?

    http://i.imgur.com/enSEB2u.jpg

    Looks like the chainset is a square taper compatible jobby. I can see the threads in the centre where you would screw in the crank puller tool. That being the case then the UN55 is an ideal replacement for whatever BB is in there currently.

    If you don't already have the tools then you'll need a crank puller

    https://www.wiggle.co.uk/park-tool-comp ... 6wQAvD_BwE

    Above is the Park Tools model - you can buy cheaper but I would stick with the quality item.

    You'll also need a BB removal tool as linked to below

    https://www.chainreactioncycles.com/par ... D_BwE&mx=a

    Plenty of online videos to show you the way - the link below should be a start

    https://www.youtube.com/watch?v=HSRS_rn5fEA
  • keef66keef66 Posts: 13,123
    I'm guessing from that pic that it's square taper. Best take off the cranks and whip the BB out to see what's in there. Could well be a UN55 but you need the same length to maintain the chainline.
  • keef66keef66 Posts: 13,123
    ^ must try to type faster...
  • barongreenbackbarongreenback Posts: 229
    Is this your bike? https://www.evanscycles.com/specialized ... e-00126023

    If not, Evans are quite good at keeping listings of old stock, which is good to compare spec. If it's the one above, then a new UN55 will be all you need.
  • VizzageVizzage Posts: 32
    Thanks everyone! Wow, fantastic! And yes BGB that’s exactly my bike. Awesome, cheers!
  • Vino'sGhostVino'sGhost Posts: 4,129
    Mmmmmm bottom brackets
  • barongreenbackbarongreenback Posts: 229
    I love having BB90 on my Trek. So reliable, so easy to maintain*

    *lies
  • Vino'sGhostVino'sGhost Posts: 4,129
    barongreenback wrote:
    I love having BB90 on my Trek. So reliable, so easy to maintain*

    *lies


    Mmm longlasting, maintenance free......

    Long live the screw-in bottom bracket
  • VizzageVizzage Posts: 32
    Hi again,

    Ok. Taken out the BB. The label’s gone but it has stamped on it: RPM BB-7420, and on the non-drive-side taper it has 113 stamped.

    So, final question, what is the very best “direct replacement” for that? Cheers
  • Vino'sGhostVino'sGhost Posts: 4,129
    Vizzage wrote:
    Hi again,

    Ok. Taken out the BB. The label’s gone but it has stamped on it: RPM BB-7420, and on the non-drive-side taper it has 113 stamped.

    So, final question, what is the very best “direct replacement” for that? Cheers


    Is it English or italian thread? i.e did the driveside undo the wrong way (english)

    anyway order here https://www.chainreactioncycles.com/shi ... -prod71369
  • VizzageVizzage Posts: 32
    The non-drive side was normal; the drive-side I had to turn clockwise to undo.
  • Vino'sGhostVino'sGhost Posts: 4,129
    Vizzage wrote:
    The non-drive side was normal; the drive-side I had to turn clockwise to undo.

    Thats English.
  • VizzageVizzage Posts: 32
    edited January 2019
    Brill, ta, ordered one. Then decided to make a “minor tweak” to the derailleur and ended up having to spend 3 hours on all the little adjustment screws, gear cable adjustments, nothing seemed to work - I even had the chain off and in a bucket of turps at one point. Thankfully back together now and seems to be working. Mightily relieved. And the creaking’s still there thank goodness.
  • Vino'sGhostVino'sGhost Posts: 4,129
    lol after this youll be comfortable repairing anything on your bike ololol
  • VizzageVizzage Posts: 32
    Right, replaced it with a lovely new shimano un55 and it’s 100% gorgeous. Thanks all for your help.
  • Vino'sGhostVino'sGhost Posts: 4,129
    Vizzage wrote:
    Right, replaced it with a lovely new shimano un55 and it’s 100% gorgeous. Thanks all for your help.

    Nicely done :D
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