hansel

Hey,
i had a noise when i would crank over my old crank. i replaced the crank with a new one from my old bike, that i know is straight. now the noise is still happening its when i crank hard, but not when im just cruising at a steady cadence. my friend says its the chain, but i think its the bottom bracket. i also think there is some left to right twist in the crank but cant be sure. but i know its not the crank.

thanks

mrvrsick

Without knowing what components you have, I would guess it is the chain rubbing on the front derailer (or derailleur for some of you)

hansel

nope its not that, sorry for not adding that. im using the bb that came with the frame. its an relatively old trek. it dosnt look like its sealed, its not flush on the outside of the frame, it has the mount for the pedal arm, than it does in about 1/4 to 1/2 of an inch.

mrvrsick

Square taper? If it has an adjusting lock nut on the non-drive side it's probably a lose ball bearing system. If so, adjust the play in the non-drive side, make sure the crank bolts are torqued correctly, check the pedals (just a thought), and if that doesn't fix it, take it apart, solvent on the parts, re-lube, install.

wcoastbikr

Tear apart the BB, clean, relube, and put it all back together. Similar thing happened with my modern shimano BB. Do you ride through a lot of rain or wash your bike with a hose? You can get a lot of junk in there, mine was pretty filthy. Cleaning and lubing fixed the noise.

hansel

ive never taken off the bb on this bike. i don't know if it is threaded. posting pics.

kayakdiver

Funny.... I just had a question about my RD and I posted it in the Mechanics forum

hansel

haha im assuming you dont know the answer than? haha i get the hint. thanks