[Closed] Bike Maintenance - creeking cranks

I believe sometimes the pedals can make such noises? i am ready to be corrected... but i am sure they can if they aren't happy so might be worth a look....

IME they start to creak as the bearings wear. The cure is new BB/bearings, depending on type

If i ride hard the cranks seem to creek, if I don't nothing. Hmmm..to be honest I hadn't suspected the pedals.

Its been a while since I had the BB out. Is it an easy job to fixed the bearings? I've got splined middleburn cranks on I think a Raceface BB.

Sounds like an ISIS BB so It'll be a sealed unit - you won't be able to access the bearings. Had a Truvativ unit on my bike originally, when I took it out I found rusty water leaking out of it - spinning it felt like it was full of gravel. Replaced it with an SKF one.

Depending on the creek you're getting you might fix it by greasing the BB theads - had this problem myself a number of times. Also check the chainring bolts.

SKF one? It really has been a while..a little too long me thinks.

Thanks for reply I'll have a look at the weekend at it.

Ok googled SKF
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looks eh, like a BB..hmm.. I'll refrain from witty comments til I know you a little better 😛

Main advant. of this unit over the old one, basically you can maintain it, whereas I'm guessing if i take my BB out it'll be all one big mess and I'll have to send it to the manufacturer if I want it sorted, bummer. Or just swap it over, which will be easier 🙂

OP - pedal/crank thread and chainring bolts can creak also, as can bb in bb shell.

People often think it's the bb creaking but IME/O it's more likely one of the threads...and as installation of a new bb means greasing threads and tightening everything up that does solve it (at the expense of possibly not-needed bb).

Personally never had a creaking BB until the bearings were falling apart, and even then it was bearly noticable. Far more often I've found it was the actual arm/shaft interface. Mind you, a lot of those were on square taper arms. Recently had ring bolts creaking like mad.

Could it be as simple as the crank bolts loosening off a little so the cranks are a little loose? I usually check the bolts on my Octalink setups every now and then. I think too that the recommendation is a bit of copper grease on the splines (dry for square tapers?). It might be worth checking that the pedals are tight too.

IME virtually everything that creaks on a bike sounds like it's coming from the bottom bracket, which isn't always the case (seatposts for example).

cynic-al, I'll give it all a look over..any recommends on a decent grease (as I don't have any at the moment)?

coffeeking, how'd you mean by

"Far more often I've found it was the actual arm/shaft interface..."

so this is the arm of the crank and the shaft of the bb, but only a bolt to tighten this up but can be done about it?

With the older square taper BBs (and I remember my brothers raceface doing it too) the arm sort of "settles" on the spline - if you dont catch it early, or just tighten it up you end up either splitting the crank or with a rounded spline/tooth interface. If my cranks ever creak I remove the offending side, clean thoroughly both the arm and shaft, and re-assemble them dry. Never been a fan of lube on splined or SQ-taper shafts as it becomes very easy to over-torque the bolts and screw up the crank arm. As mentioned above - check ring bolts (create and almost identical creak) and make sure its not your seatpost transmitting the sound downward (less likely but possible if you're sat while it happens)

thanks and as for decent grease?

Grease for bearings - usually I re-assemble with waterproof marine grease but it is pricey, general purpose molybdenum grease doesnt seem to last as long for me but if you give it TLC more often it should work fine. For the purposes of bike bearings your main worry is keeping water out, rather than lithium fandabidozy super-lubes IMO, but some will probably be able suggest a more easily available generic bike grease for you.

leftfield

I had a similar problem once, thought it was my cranks but nothing worked. Then I cleaned, greased and tightened my seatpost (where it goes into the frame, not holds the saddle). heh presto.

/leftfield

keep WD40 away from bearings.. it'll kill them in double quick time.

Creeking could of course be dead bearings and the creek being balls that are sticking/rusted within the race.. it could also be lots of other things as others mentioned above.

WD40 is a very light lubricant, hence not good for bearings. Use it to clean them by all means, but dont use it in place of lube 🙂

For the purposes of bike bearings your main worry is keeping water out, rather than lithium fandabidozy super-lubes IMO

What do yo mean by rather than? does it mean lithium based grease's aren't good enough, and why?

IMO/E lithium grease is not the best, does not last that well, overpriced.

Castrol stuff (LM?) has done me well recently - Hellfrauds

I wished I had read that message a few days ago...oh well. Got me some high performance merc bearing grease, so says on the tin, seems okay not too expensive anyway. Took the cranks and pedals off and gave it a good clean/grease, no more creeking 😀

Take it all apart, clean, regrease and put back together. Does the creak happen at a certain point in the pedal stroke? If it's the same point every time it could well be worn bearings in the BB. If not then more likely to be something loose

LM grease on bearings, copper grease on threads!