zactaylor

Developed a random creak on my 'summer bike' coming from the bottom bracket/crank area.

Its press-fit bottom bracket was troublesome when the bike was new; it took about 6 months to get it to work properly. The non-drive side pressed cups would very slowly rotate inside the frame as it was being ridden and would creak when pressure was put on the non-drive crank. One ride would result in about 1/4 turn. After 3 attempts (the latter two involving Loctite 641 compound) the bottom bracket eventually stayed and the creaking went.

A similar sort of sound returned recently except it was less consistent and seemed to only be happening when I rode out of the saddle. It would only do it at one particular point in the pedal stroke. The cups were not rotating. I assumed it was, yet again, the troublesome bottom bracket. But, I couldn't feel or see anything wrong. I decided to keep riding it to see if it would get any worse, hopefully making it easier to figure out what it was. It didn't get worse. It would sometimes take about 15 miles of riding before it would start. I was baffled.

I decided to try putting a different pair of pedals on the bike. This didn't stop the problem but I am convinced that it made it quieter. I thus assumed it wasn't the pedals so put the 'originals' back on. When I did this, I gave the threads (both inside the crank and on the pedal axle) a good clean and regrease. I have since ridden the bike twice (one 30 mile ride and one 50 mile ride) and the noise seems to have vanished. This leads me to the conclusion that it was something to do with the threads on the pedals/thread inside the crank arm and that the cleaning and regreasing fixed it. I do not understand how the threads can creak though? Seems very odd to me. There isn't anything to creak on the threads?

I am glad the noise is gone, and I hope I won't be eating my words in a few days time, but I just wondered if anyone had any idea what might have been going on?

KerryIrons

Why do you say this? Metal to metal can always creak if it is not greased. That describes your pedals threaded into your cranks. If/when you can find the source of this kind of noise, cleaning and greasing is almost always the fix.

superdex

I had a creak on a new bike I could /not/ figure out, thought it was the BB. The crank arms. The pedals. Nope, Nope and Nope.


Turns out with a this pedal (Crank Bros Candy) and shoe (Giro) combo, my toe was hitting/rubbing the crank arm on the downstroke as I pedaled, causing the squeak.

Ghazmh

I chased a creak on my road bike for weeks and it turned out to tube the front quick release.

zactaylor

Because if the threads of the pedals are screwed in to the 'female' threads on the cranks, and are sufficiently tight with no play, then surely they shouldn't actually be moving to creak? There shouldn't be any rubbing between the male and female thread. I appreciate stress is being put through it as you put weight on it but nothing is actually rubbing against anything.

I'm not an engineer!!

zactaylor

Tried that too. Definitely something bottom bracket/crank related.

KerryIrons

I am an engineer. Unless there is a perfect fit between the pedal threads and the crank arm threads (there is NOT!) then there is the possibility of movement. Simple as that.