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My crankset is driving me nuts, because of creaking noises when pedaling.

I have fixed the issue twice already, by removing the bottom bracket (FWIW, it's a 68x115mm square, pictured below, and my frame is aluminium), cleaning everything up and installing it back, with some fresh lithium grease. However, the creaks come back soon, like after a week or two (about 30km ride per day), or after some heavy rain.

I had been tightening the strongest I could, but using a simple 24mm wrench, with the bracket tool ripping off again and again... Note that every time, the subsequent disassembly was very easy. I guess I wasn't tightening strong enough. As I have to fix it again (*cries softly*), I just bought a 300mm torque wrench, and will tighten to 40~50 Nm.

Long story short, am I right assuming I wasn't tightening strong enough?


Update: So, I've just spent 3 hours cleaning (this time very, very thoroughly) and reassembling everything. About the torque, 50 Nm is not as strong as I thought, and I think I fastened strong enough the previous times. When I rode the bike afterwards, there were the exact same creaks are before (*cries softly*). But after like 1~2km, they disappared, and no noise for the rest of the ride (about 10km, under heavy rain). In fact, that's also what happened the previous times…

But after I have reinstalled the crankset, I turned the pedals by hand very fast, with the chain removed. Looking at the screw head of the left arm, I noticed it was very, very slightly waving. Which indicates the axle is slightly misaligned or bent.

Thus, I begin to suspect the culprit for the creaks is the bottom bracket itself. Do you think my assumption is right?


Update 2: So, today, the annoying creaks are back, exactly as before (*crying intensifies*). Maybe it's the BB itself, but I'm also suspecting the chainwheel aluminium bolts (even if I've greased them), and the pedals (magnesium platforms, which seem to easily propagate noise). I'll have to proceed by elimination… Also, note that after a sudden rain (again…), the bike got very wet and apparently it makes the creaks to disappear.


Update 3: After some trial and error, found it! It was the pedals, as simple as that… Some AliExpress titanium pedals, great at first glance, but that degraded fast, and with many design errors (here for instance, I cannot disassemble them because there is not enough room for the head of the socket wrench). Thankfully, AliExpress already had reimbursed me because of conception errors of this product. It's a shame because they were lightweight and there isn't much alternative, but the creaking noises are a huge no-no for me. Basically I just eradicated 95% creaking noises of the bike :)


VP-BC73 68x115mm

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    and you're sure the creaking noises aren't caused by the pedals? have you tested it with a different set of pedals yet? Feb 2, 2020 at 1:16
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    a crank arm not being tight on the spindle can also be a cause of creaking noises Feb 2, 2020 at 1:18
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    There are many many causes for creaks that seem related to the cranks. I had a crack in my seatpost clamp that I swore was from the crank. Rather than applying silly levels of over-torque, try one-foot pedal drills, riding out of the saddle, and pedalling backwards to try and isolate it down.
    – Criggie
    Feb 2, 2020 at 1:55
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    I believe the problem is that the cheapo bottom bracket in the picture. Decent square taper JIS bottom brackets aren't expensive, I'd replace it when disassembling it next time.
    – ojs
    Feb 2, 2020 at 10:16
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    I have tried other pedals, and pedaling standing up: also noise. Pedaling backwards: no noise. There is no noise if not forcing at all on the pedals. Currently I'm assuming it's the BB threads, but maybe it's the BB itself (bearings under load), or bad junction at the squared crank arms. I'm considering replacing the BB indeed, as it's a cheap component. But until I get the part, I have to fix the bike asap, so I'll have to disassemble/reassemble again, and hope it holds at least two weeks… Feb 2, 2020 at 13:52

1 Answer 1

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Locktite blue (also known as 243), or other similar thread lock liquids may eliminate the bottom bracket threads coming loose.

Another method to stop creaks between the BB and the frame is to use plumbers teflon tape. Just one or two wraps on the BB threads before installation will keep the bottom bracket from backing out and fill voids to eliminate movement and creaking.

Many times simply cleaning and greasing the BB and frame threads will also fix the problem.

If the problem disappears for a while after disassembling and reassembling, the bottom bracket and cranks then the BB/shell interface likely is the source of the problem...

-BUT-

Creaks can come from many sources yet they will sound like they are coming from the bottom bracket. Some other common sources to check:

Cassette: Tighten down the lockring. I've had this happen to me a couple times.

Seat rails were sliding where they went inside the saddle. The creaking disappeared when I stood.

Handlebars creaking inside the stem. Fix by lubing the bars and reinstalling.

Stem to steer creaking. Disassemble, clean, grease, reassemble.

Chainrings on crankset: Loosen and retighten the chainring bolts.

My recommendation is to fix one item, see if the creak persists and if so move on to the next.

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    @GrasDoublen I have used Teflon tape on most threaded BBS. It didn’t make installing it tighter. I recall tape being suggested by at least several experienced forum posters. Manufacturers often suggest oil or other preparations on spoke nipples, loctite on some bolts, carbon paste to keep some carbon posts from slipping, etc. Teflon tape seems no worse than any of this stuff. It seems markedly more sensible than the things people sometimes need to resort to to quiet noisy press fit BBs.
    – Weiwen Ng
    Feb 2, 2020 at 23:49
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    Apparently cracked frames can creak as well.
    – Michael
    Feb 3, 2020 at 12:13
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    And wheel problems can cause creaks that coincide with pedal strokes as well. I had a creak that coincided with the down/power stroke on the right (IIRC) pedal that I simply could not find despite quite a bit of time and effort. The creak finally disappeared when the crack that was at a spoke hole in the front rim grew large enough to allow the well-used (10k+ miles) front wheel to go out-of-true. New front wheel, no more creak. Feb 3, 2020 at 12:47
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    I'd add skewers as a potential source of creaks that sound like they might be from the bottom bracket. I had one skewer nut crack (lightweight skewer, was a weight weenie in past life, go ahead and laugh if you wish). It creaked.
    – Weiwen Ng
    Feb 3, 2020 at 18:52
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    I'm accepting your answer. Just one thing: as I read on some forums, the Loctite on BB threads isn't a proper fix at all ;) Feb 6, 2020 at 23:36

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