Brand New Chainset, on a new BB, creaking

mattrixdesign2
mattrixdesign2 Posts: 644
edited January 2015 in Workshop
A few months ago I had a new 105bb fitted to my CX bike, along with the triple chainset, all running smooth and silent.

Recently removed the triple, installed a CX50 double, ran smooth and quiet, since a CX race on Sunday its creaking badly on the commute to work.

Pretty sure its the BB/Chainset, pedals seems OK - tested by some single foot pedalling :D .

The bolts on the chainset arms were tightened up evenly and with a torque wrench. What are the obvious places to start to try and fix the noise? Where should grease be, where shouldn't it be, any thing else to check?

Runs dead smooth, just noisy, sure there are some obvious processed of elimination.

Comments

  • pinno
    pinno Posts: 51,804
    - Did any moisture get into the BB during the cx race? A tiny bit of moisture can cause creaking but usually only under a little pressure. Did you get some dirt in the cups?
    - I would be also inclined to re-tighten the chain rings - go by feel, not a torque wrench. CX will exploit any weaknesses.
    - Have you checked your cleats? I got creaking from one pedal once and despite everything being A1, I ended up spraying some silicone on the cleat, it was the only cure.
    seanoconn - gruagach craic!
  • 1: very very very muddy race, followed by jet hose! - so thanks for that - I shall strip and dry, where should grease be? In the shaft and were the cranks fit? Perhaps best not use the jet hose again, thought I was being careful, obviously not, some of the gear/brake cables must have water in them too, as the cables froze on some commutes. Its bad to jet hose, lesson learnt.
    2: ok will do
    3: I am pretty sure its not pedals, but will cross check.

    Thanks

    Matt
  • keef66
    keef66 Posts: 13,123
    If it's been pressure washed, it's possible you've forced water past the seals and into the BB bearings. I'd whip the chainset off and remove the BB cups. If they feel at all rough when turning the inner part by hand then buy a replacement. If they feel smooth you could try drying them somewhere hot for a couple of days. Alternatively it may be possible to carefully pick out the seals and get at the bearings to clean and regrease them. Plenty of grease on the BB threads when (re) installing the cups; the creaking might be coming from there.
  • Matthewfalle
    Matthewfalle Posts: 17,380
    Copper slip all the chainring bolts, tighten back up using equal amounts of turns on each one in a diagonal direction - just don't do up tight one then move onto the next. Half tight, then next one half tight and so on so equal tension and pressure across the c/ring.

    Check that your cleats aren't worn or damaged and therefore causing the aforementioned noise.
    Postby team47b » Sun Jun 28, 2015 11:53 am

    De Sisti wrote:
    This is one of the silliest threads I've come across. :lol:

    Recognition at last Matthew, well done!, a justified honour :D
    smithy21 wrote:

    He's right you know.
  • k-dog
    k-dog Posts: 1,652
    I had that in the summer with a fairly new BB. The noise was driving me mental. Ended up taking the cups out and a spoonful of water was in there. Greased threads all back together and silent since.
    I'm left handed, if that matters.
  • cycleclinic
    cycleclinic Posts: 6,865
    Pressure washers should not be used on bikes they ruin BB's, hub bearings, headsets e.t.c

    A rythmic click/creak at particular point in the pedal stroke is normally, chainring bolt, pedal or BB related.

    Apply antiseize to chainring bolts and pedal threads anyway but the BB may well be sour now. There is no fixing it you will need a new one. Next time you want to clean the bike use a bucket and a brush it is the best way.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • I took the chain set off, some crap between the crank arms and the bottom bracket, i.e. lots of matted grass.

    Took it out, dry inside, and the BB was dead smooth. I didn't fiddle with the chain ring bolts, as I need to get a proper tool for back of the bolts, will tighten tonight and see how it runs on tomorrows commute.