Bottom bracket-like creak temporarily resolved by tightening rear QR

andyeb
andyeb Posts: 407
edited June 2018 in Workshop
I have a weird creak on my Pinnacle Arkose 3 (disc brakes with tradition QR, not through-axle) - it sounds like a bottom bracket issue. Except that has been replaced and adequately re-tightened.

I've found that the creak goes away temporarily if I tighten the rear quick release, however it returns within a few miles. I've tried swapping in a different QR (the one from my turbo trainer) and this makes no difference. I've also tried tightening the bolts which hold the rear derailleur hanger, which the QR tightens against.

What else should I check? It's maddening and I'm concerned something is fatigued/about to break.

Comments

  • timothyw
    timothyw Posts: 2,482
    Check the locknuts/cone tension on the wheels?

    Otherwise check the other usual suspects for creaks that sound like bottom bracket creaks - saddle rails, seatpost, headset etc.
  • jermas
    jermas Posts: 484
    Remove the rear derailleur hanger, clean then put some grease on the back of the hanger and re-bolt to the frame. Sometimes the hanger can creak whilst pedalling when installed dry ie without grease.
  • sungod
    sungod Posts: 16,541
    freehub bearings can creak if they start failing, happens only under power (you don't mention whether creaking is constant or not)

    try removing the wheel and see if you can feel any roughness/excess drag when turned
    my bike - faster than god's and twice as shiny
  • andyeb
    andyeb Posts: 407
    Thanks everyone for the help.

    I checked the rear bearing and it is a little notchy.

    I'm quite comfortable stripping down cup-and-cone bearings, but looking at the wheel design, I've not seen this type before and don't know where to start taking it apart:

    https://imgur.com/a/7v9BNuS

    Does anyone know how I would go about accessing the bearings on this design? Normally I'd just remove the rubber boot on the non-drive side and get my cone spanners out. However the equivalent piece on this design is hard plastic.

    I've also noticed that the aluminium frame is a little "chewed" in one place on the drive side (probably as a result of me tightening up the QR regularly) - I've highlighted this in red on the photo, which also suggests the frame dropout is not exactly square with the axle.

    Does anyone have a suggested resolution for this? The bike has never been crashed, so I can only assume it's been this way from new.

    Many thanks,

    Andrew
  • sungod
    sungod Posts: 16,541
    what model hub? or what model are the wheels if you don't know the hub

    the end caps may simply pull off, maybe cartridge bearings inside

    the freehub itself may also have cartridge bearings
    my bike - faster than god's and twice as shiny
  • andyeb
    andyeb Posts: 407
    No visible markings on the hub but the specifications simply say "KT sealed bearing rear hub". Does that effectively mean I have disposable wheels?!
  • sungod
    sungod Posts: 16,541
    sealed bearings typically means cartridge bearings (ball bearings in races with seals)

    only takes a minute to find some kt info with a search...
    http://www.kttw-hub.com/lib/dl_file.php ... UCTION.pdf
    http://www.ktgroup.net/lib/dl_file.php? ... alogue.pdf
    ...maybe you'll match your hub

    i'd check the freehub bearings first, they may fail before the hub bearings, if bearings are just dry/dirty you may be able to pop the seals and clean/regrease in situ

    there are generic guides showing what's typically involved, for example...
    https://www.artscyclery.com/learningcen ... gcare.html
    my bike - faster than god's and twice as shiny
  • Wizzybit
    Wizzybit Posts: 8
    I had a creaking noise that i was convinced was the bb too.

    Turned out mine was the QR skewer, i removed them and cleaned them and gave them a good spray all over with some gt85, springs and everything and then wioed all the excess off, my noise went instantly.

    I realise you mentioned you changed QR, but both could be dry and need some oil
  • Vino'sGhost
    Vino'sGhost Posts: 4,129
    Singed sounds on the money, they’re often replaceable.