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Squealing noise when pedalling

Hello All, hate to be the person who's first contribution to a community is requesting help, but here I am. Summary
1) Bike: Cannondale Carbon Synapse 105
2) Noticed a progressively loud squeal (not a creak) when pedaling
3) After checking various items, I removed the crank/ bracket cleaned and re-greased. Squeal remains
4) I believe I have found the culprit. Its a silver ring where the crank attaches, when moved around it makes a high pitched noise. I couldn't remove this part (or don't know how)
*Note I use bike shops for maintenance normally as confidence in this is low, however thought I would try and save money :)

I tried attaching a vid on iPhone of the noise by format not allowed - happy to share as assume that will help - I have pic of the offending item

Posts

  • whyamiherewhyamihere Posts: 7,465
    That's the inner race of the bottom bracket bearing, if it's making a squealing noise it's going to need to be replaced. On a Synapse, that's going to be a BB30 bottom bracket. It's certainly possibly to DIY the replacement of the bottom bracket, but it requires specialised tools and skills.
  • That's the inner race of your bottom bracket bearing which appears to be push fit. Suspect the bearing is one dry hence the squealing.

    You'll need to remove using a drift or bearing removal tool making sure the bearing comes out square to the BB shell.

    Then install a new BB bearing (same size) using a press.

    If you haven't got the tools then it may be LBS job.
  • Thanks both for the speedy response - it does look like a bike shop job, and beyond my skill set. Much appreciated - its killing any enjoyment of cycling :(
  • david37david37 Posts: 1,313
    Hi Chaz, given youve got this far Id say it's not beyond your skill set. though you might not have all the tools. here you just need a couple of drifts for a few quid off the bay, and a bit of bar to keep everything square.

    Knock the old bearings out, walk them out a bit at a time with a punch or old srewdriver. They can need a bit of welly, but just feel your way into it. Clean it all out.

    Using the drifts you bought press the new bearings in, making sure they stay square and also buy and use bearing retianing compound. this ensures you dont get any creak.

    For a bike shop that knows what it's doing this job is straightforward as they will have the tools and the experience and confidence. You can do it for yourself and afterwards you'll wonder what the fuss was about.

    The key to making this a success is the quality of the replacement bearings, Cleaning everything, using bearing retainer and pressing the new bearings in straight.

    take your time you can do it. And it will take less time than it takes to get the bike to the bike shop and q up.

  • brundonbianchibrundonbianchi Posts: 689
    edited 4 February
    You can make something to knock the bearings out of the frame by cutting slats into the end of a short length of sink drain pipe with the correct diameter to fit through the centre of the bearings. Then back the slatted end of the pipe onto the bearing, and tap them out with a wooden or rubber mallet ( or if you want to keep the purists happy, a dead blow hammer ). Pressing the new ones in is easy enough if you have a small square of wood to make sure they go in flat. There are purpose made drifts and presses available, but they cost a fair bit more than the equally effective bits of pipe and wood, and unless you have lots of bikes, won’t get much use.
  • First.AspectFirst.Aspect Posts: 6,248
    When you say re greased, did you do the bearing itself?

    If not, try picking the black cover off with a small tool, repacking with grease and replacing.

    Chances are your bearings have taken some abuse in there but you might get a bit more life out of them.
  • david37david37 Posts: 1,313

    You can make something to knock the bearings out of the frame by cutting slats into the end of a short length of sink drain pipe with the correct diameter to fit through the centre of the bearings. Then back the slatted end of the pipe onto the bearing, and tap them out with a wooden or rubber mallet ( or if you want to keep the purists happy, a dead blow hammer ). Pressing the new ones in is easy enough if you have a small square of wood to make sure they go in flat. There are purpose made drifts and presses available, but they cost a fair bit more than the equally effective bits of pipe and wood, and unless you have lots of bikes, won’t get much use.

    ignore this, a bit of pipe and some wood is NOT as effective as a purpose made drift or bearing press. Unless you dont mind the bearings sitting at the wrong angle or the wrong place.

    In any case, you can pick up a basic chineesium one for less than £20 and get a load of other drifts for wheel bearings etc with it. look on the bay. 6806 is the bearing size for BB30.

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