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unbonded bottom bracket insert?

kieron_67kieron_67 Posts: 161
edited August 2012 in MTB workshop & tech
Aup guys

Having some trouble with my crank creaking quite loudly

the crank is an older style shimano xt with the octalink bb.

its fitted to a carbon 456.

ive changed the bb for a brand new one and also checked all bolts, removed the whole assembly cleaned greased and fitted and its still the same, thought it may be the pedals but they seem to be spinning freely. Am going to change the pedals and try it to see if that makes any difference.

any other thoughts from anyone?

thanks

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    seat post.
    bars,
    controls.

    read the info on Parktools and work your way through.

    could it be the threaded insert? presuming it has one.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • kieron_67kieron_67 Posts: 161
    definatly something to do with the cranks it only happens with pressure of the pedals, nothing when rolling.

    i'm worried it could be the insert.
  • nicklousenicklouse Posts: 50,675 Lives Here
    like i said read park tools and work your way through. it is most likely to be nothing to do with the cranks.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • edhornbyedhornby Posts: 1,780
    as well as all the above

    could be the chainring bolts
    could be the deraileur in the hanger
    could be the wheel skewers need tightening
    could be the seat in the seatpost
    "I get paid to make other people suffer on my wheel, how good is that"
    --Jens Voight
  • nicklousenicklouse Posts: 50,675 Lives Here
    edhornby wrote:
    as well as all the above

    could be the chainring bolts
    could be the deraileur in the hanger
    could be the wheel skewers need tightening
    could be the seat in the seatpost
    Most of which are covered in the Parktools topic.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • BigchrisBigchris Posts: 131
    My crank sometimes creaks when I've been putting alot of pressure on the pedals, like doing a uphill in a high ish gear.It creaks like some things cracked? Not 100% sure what it is, but i assume its to do with the crank going back into its slot properly. Might try tightening the crank bolts.
  • GinjafroGinjafro Posts: 572
    I was convinced a had a creaking crank until that is...

    I realised the rear brake cable was making the creaking noise at the slightest turn of the handlebars. I suspect the outer sheath may be a tad too short. This is because a couple of months ago I swapped the stem for a longer one and thinking about it, that was when that annoying creak started!
    Giant XTC Pro-Carbon
    Cove Hustler
    Planet X Pro-Carbon
  • kieron_67kieron_67 Posts: 161
    Still suffering with this.

    Ive changed the BB, changed the crank arm bolts, chain ring bolts, had it off numerous times,

    The aluminium insert looks to be still bonded in the frame, there is a few supicous marks but nothing that i dont think suggests that it is that.

    Really beginning to get anoying now.

    Its not doing it when i first set out, i do the commute to work which is 7 mile each way. on the way to work its fine, the minute i set out from work its creaking and cracking. seems like the arms are coming loose from the bottom bracket.

    Maybe next step is a new crank set to see if that sorts the issue.
  • The RookieThe Rookie Posts: 27,803
    Creaking stop if you stand up out the saddle?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • kieron_67kieron_67 Posts: 161
    hi guys

    been hearing alot of noises from my cranks recently on my 456 carbon, taken it apart today to be met with this, you can feel the laquer edges on the insert and it looks like its cranking around the insert and this could be causing my noises.

    just wanted your thoughts on it before i give on on-one a ring tomorrow see if i can get it sorted under the warrenty as its only a few month old

    heres the pics one of either side

    SDC10648.jpg

    SDC10651.jpg

    thanks
  • nicklousenicklouse Posts: 50,675 Lives Here
    my thoughts.

    email them the pictures now and then call then tomorrow.

    was the bike bought or built?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • kieron_67kieron_67 Posts: 161
    yes it only creaks while pedaling when the bottom bracket is under load, i think its the insert coming unbonded from the carbon, ive posted a picture of it in another thread in workshop section.
  • kieron_67kieron_67 Posts: 161
    the bike was built

    yea ive sent them the pictures of it
  • nicklousenicklouse Posts: 50,675 Lives Here
    topics merged.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • The RookieThe Rookie Posts: 27,803
    Creaking stop if you stand up out the saddle?
    Can you answer this question rather than another one no-one asked please?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • kieron_67kieron_67 Posts: 161
    kieron_67 wrote:
    yes it only creaks while pedaling when the bottom bracket is under load, i think its the insert coming unbonded from the carbon, ive posted a picture of it in another thread in workshop section.

    i did answer the question, the topic was merged so it didnt appear anymore under your post.

    but i think i misread the post, if i stand up and dont pedal it dosent, if sitting not pedalling it dosent creak. if i stand up and pedal it still creaks but dosent seem as bad. it seems to creak more when i am sitting but creaks either way.
  • The RookieThe Rookie Posts: 27,803
    that answered the question, the first responds did not which is why I asked it again......
    that reply does suggest a BB issue, although a mate took a while to realise a similar noise was loose rear qr!
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • nicklousenicklouse Posts: 50,675 Lives Here
    my ha'penny worth that BB needs facing.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • gmaczgmacz Posts: 343
    I had a problem with mine after I switched it for a new one.
    Ran it for a while and kept checking tension on the bolts.
    In the end I changed it for another one and... the noise was still there.
    Sitting pushing hard and it was bad ,standing and pushing hard it was not so bad.
    Problem solved- it was the seat post.If it happened again, I would remove seat post and go for a small run and see if noise was still there.
    Try it.
  • bails87bails87 Posts: 12,998
    My C456 creaks occasionaly. I think it's the dropouts and/or the rear QR. It could easily be mistaken for BB noise because stamping on the pedals puts force through the chain, to the back wheel and cause the noise.

    Have you checked the dropouts are nice and tight? Put some threadlock on them?
    MTB/CX

    "As I said last time, it won't happen again."
  • kieron_67kieron_67 Posts: 161
    I checked the seat and post seemed fone. I havent checked the drop outs but i will tonight. I am 99 percent sure its coming from the cranks.

    Ive emailed the pics to on one and he suspects it is the insert he has now sent the pictures to the manufacturer to see what they think.
  • kieron_67kieron_67 Posts: 161
    just thought would let you guys know that it turned out it was the insert at fault and on one have now exchanged my frame for a new one. they didnt have my colour in stock so upraded it to the black and grey which i think is a limited edition colour set.

    thanks for all the help anyway guys.
  • DodgeTDodgeT Posts: 2,255
    What was the actual fault with the insert? Can't tell from the pic whether it s a hairline crack or lacquer over run?
    Did they say whether others may be affected, all, or a batch etc?
  • kieron_67kieron_67 Posts: 161
    what ever they bonded the insert in with had cracked and the insert was moving in side the frame slightly causing a creaking sound when under any pressure. They said it was the first one of the 456 that they have had back with this issue so i dont think there is any problems.
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