Bicycle Mechanics - Bang Bang Bang

So i'm sure i've posted this before, but the problem still persists.

Whenever i go out on a ride, my bike makes a really annoying 'banging/clicking' type noise. At first i thought it might be the sensor on my front wheel hitting the spokes as it went around (pretty constant noise) but upon watching it go around and completely being away from the area when the noise sounded, i determined this was not the cause. I adjusted it to be sure but problem persisted.

For a second, i thought it might be a waterbottle bouncing around, but clearly thats not the case. So maybe something to do with chain/deraileur? No contact there, and the noise continues even when i stop pedaling.

So i focused my hearing as best as i could and believe the noise is coming from the bottom bracket, where the pedals are connected. I have no idea what is causing said noise to come from this area. I believe i've taken the bike in to two different shops to 'fix' the problem (i only knew it to be a clicking type sound and they both looked puzzled) so any suggestions?

I miss being able to enjoy the natural noises a bike makes as you ride.

loose ball bearings? just a guess...

A loose spoke will make a popping sound. Check wheels for even spoke tension.

No, its definitely coming from the BB area. Its more of a clanging noise...metal on metal, and occurs once-a-second or so - it does not vary due to my speed. Its not coming from a wheel but very low on my bike and right below me - which can only be the BB.

Could be loose fender attachment, or stand. Since the frequency is does not vary with speed it is most likely a loose part shaking.

if it is a DS bike with a coil shock it could be too much preload. I remeber hearing something liek that when I rode my first X-mart bike that was DS.

If it happens when you're not pedaling, it can't be your Bb.

How can it not vary with speed or pedaling? If you're stopped, it's still doing it?

I suspect you have a woodpecker.

Its a Titanium Merlin Road bike. It only makes the noise when i'm moving. The noise continues when i stop pedaling and coast. If i lean down and pay close attention, it is definitely coming from the BB area. Theres nothing else in the vicinity (obviously) and its not coming from the rear tire. And its a really annoying sound.

Everyone here has been sure a noise was coming from one area when it turned out it was coming from another. So, please be patient with us if we keep suggesting other possibilities.

In that vein, I suggest looking into whether it could be the interface between your saddle and post. If so, grease it all up.

jim

Have you been here yet? http://www.sheldonbrown.com/creaks.html

Gnomes with tiny hammers and an enviable sense of rhythm.

I'm pretty sure its not my saddle, though i'll double check that. Based on direction of the sound and its pitch, when i lean down to listen to it closely, it seems to be originating in the BB area. If it was the seat, then wouldn't it stop when i stand (to climb?)...the type of noise doesn't sound like a rubbing type noise.

Think of putting a coin in the dryer. When it spins, it pings when it hits the bottom. I'll hop on my bike tonight and see if i can give a more descriptive...description of the noise and get my room mate to see if she can tell where its coming from.

Freehub, which could resonate through your frame?

Check your wheel reflectors if you have them. They will rattle if they're loose. Slide it so the spokes lock it in place.

Lift the rear wheel off the ground and spin it, and see if the sound is there. If it is, try and isolate it. If it's not, do the same with the front wheel. It pretty much has to be something wheel-related since it continues when you coast. If it doesn't make the noise when you simply spin the wheels without your weight on the bike, it's most likely a spoke issue or possibly something going on with the hub that only occurs when there's weight on the bike-

The description of the coin in the dryer has me wondering if it's something rattling around inside the rim.

How 'bout your crank hitting the front derailleur cage?

OK, I give up. What is it?

I had a similar noise. The OP says it does NOT increase with speed. My noise was comming from a loose buckle on my backpack, which made a rythimic sound only when moving. (wind blowing the buckle). IDrove me nuts for about a week !!! !s there anything loose ANYWHERE on your bike that bay be causing something like this ? Maybe the end of youre derauller cable tapping the frame as you move

You know what? This sounds to me like a reflector or a big valve cap blinker or something. When the bike gets up to speed, centrifugal force pulls it out and it hits the chainstays.

Matt, if you can get the back wheel up (ideally in a stand) and spin the pedals, see if something on the wheel is deforming and hitting the frame.

If this is worth anything... I had a similar noise coming from one of mine last year some time, from the BB area. I tried everything I could think of and couldn't make it stop. It was a mountain bike with the knobbies on it still. I was doing mostly city riding on it, so I put narrower tires on it. Voila! Problem solved.

When in doubt, try something ridiculous that has nothing to do with what you think the problem is. Maybe changing your shoes, or eating more leafy greens would do the trick in your case...

possibly.....a loose chainring?
A loose crank arm? my square fitting had worn out and there was play in the crank arm causing it to hit frame (chainstay)
cracked pedal bearing, loose pedal framing?

I'm going with wheel related issues since it continues to make noise when not pedaling. Loose spoke, Slight tire rub on brake shoe - Ive had this one. Freewheel/Freehub-cassette issue, bearing in hub. Global Warming?

Going with wheel issue and sound is transferring though tubes. Had one in other day said was bb and it was cassette vibration in lose cogs.

Goblins! It must be goblins!

Or maybe it's brownies.

Questions for the OP

1. It does not vary at all with road speed?
2. It does not stop when you stop pedaling?

If the answer to both is yes, then you have a strange one.
If it carries on when the BB is not turning, can't see how that is the problem.