F70Rider

I keep getting an intermitent creaking noise coming from the cranks/BB. I have taken it to my LBS and everytime they say the cranks are loose and they usually are. So I have been making sure to tighten them before I ride as well as check the seatpost and headset. However, I still get the noise after about 20 miles or so. It does not happen all the time and it does not seem to matter what gear I am in. I check the cranks when I get home and they are usually still tight. Does anybody have any ideas on what might be causing this that I have not thought of? Thanks in advance

PatWasha

I sounds like what was happening with my bottom bracket. I would get a noise sometimes every revolution, sometimes around every 10th and sometimes not at all, but usually the noise would be on the right side.

I took it into a shop by me, the owner of the shop took the cranks and was able to feel a slight side to side play. Essentially, we replaced the bottom bracket and everythings fine.

blue_neon

F70Rider - It's the bottom bracket.

I got mine replaced last week, its as smooth as smooth.

What caused it? In my case it was pedals being knocked against poles and trees etc. while riding. It somewhat damaged the bottom bracket.

I installed a new Shimanoe bottom bracket at RRP $60AU, and its great! No more clicking, nothing. No more squeeking and the bike feels like new to pedal.

PatWasha

I'm not sure what caused mine to go bad. When I got the bike, the first one lasted for about 5 years. This one only about 1 year. All I know is that I was stumped, because it wasn't making a popping sound all the time like the other one did. In fact, I was checking everything, constantly making sure all the nuts and bolt were tight. The bike shop where I got the bike and did the first replacement, just said I was getting "flex in the cranks". I didn't buy that info, went to another shop by me, riding it over there about 4 miles and the owner 1st took hold of the pedals moved them around a little and told me it was the bottom bracket. However, he took it for a spin, said the sound was probably from the bottom bracket, put it up on a stand checked the drivetrain over 1st and decided bottom bracket. Luckily, I had the old one with me(so if he had to order one, he would know what type to order),since I was also thinking bottom bracket.

After a short time, tipping him a little for taking care of me right away, I was on my way into work. Without any noise coming from my bike.

F70Rider

Thanks for the input everyone. I guess I need to get the bottom bracket checked out. It seems hard to believe that the BB already needs to be replaced since the bike is only about 3 months old and has less than 1,000 miles on it.

luke.harrison

sounds like the tapers in your cranks are deformed, which usually means you need to replace them, though if you muscle them on with some loctite on the crank bolts you can delay the replacement. Once you ride a crank that's loose for any period of time you destroy the sqaure taper interface...

jur

My BB also creaked after 1 month, quite severely. LBS tried to BS me 4 times, so eventually I wrote them off and bought a BB tool and removed it myself for inspection.

It turned out that the left cartridge bearing is not a nice tight fit on the spindle, and there is a shoulder on the spindle against which the cartridge bearing sits. It is this shoulder rubbing on the inner ring of the bearing that makes that unholy racket.

I have so far tried 3 things to quieten it: Grease (worked for a month), Loctite high strength bearing mount (worked for a week), Loctite medium strength thread locker (worked for 2 days). The bike is still under guarantee, but I have decided to just buy another better quality BB myself. I do not want to go through the pain of convincing the LBS what precisely the problem is, then convincing them that I didn't void the warranty etc. etc.