Random11

While riding today I heard what sounded like a vibration in my spokes. Getting home, I plucked each of the spokes to see if one might be loose. None of them seemed loose, but plucking them, each spoke had a definite pitch, and the pitches were quite different from spoke to spoke. I'm pretty much a novice on bike maintenance, but it would seem to me that all the spokes should have about the same tension on them, and the different pitches from spoke to spoke would indicate that's not the case on my bike. Is this something that should concern me? I never did figure out what was making the noise as I was riding.

Koyote

On the rear wheel, the spokes are tightened to different tensions on the drive side and non drive side… So they will sound different. If the spokes on the same side of the rear wheel sound wildly different, and spokes on the front wheel sound wildly different, you should probably have a shop check out those wheels.

Bill Kapaun

Rear will have different tensions per side, but all spokes per side should sound the same. DS will have higher tension.
Front non disc brake should ALL sound the same.
If disc front, see Rear.

Retro Grouch 

How wobbly are your wheels? Quite honestly, if they aren't broken, I wouldn't recommend fixing them.

Random11

Wheels are not wobbly. The bike rides fine but I just checked the spokes because of the noise I was hearing. I didn't think to see whether the tensions were different on the drive side, so will check again to see if perhaps that's why they sounded different. Thanks to all for the suggestions.

pdlamb

If you heard a "vibration in your spokes" it makes me think you may have broken a spoke, or one may be unscrewed. I'd suggest a hard squeeze on every pair of spokes to see if you missed on that broke. Make sure you pluck each spoke individually -- an unscrewed, or detensioned, spoke kind of flops instead of pinging (or ponging) when you do that. Replace or fix as needed.

Iride01 

Were you doing close to 30 mph and pounding out some power in the 11 rear cog?

Steelman54 

A vibration to me implies a somewhat continuous noise, which doesn't necessarily sound like a spoke or spokes issue. But like others have stated, I would squeeze pairs of spokes to look for excessive looseness. Excessive looseness or loss of tension to me implies the wheel would be out of true. You indicated wheel were true. Keep us posted on what you learn.

oldbobcat

Are you sure it's the spokes and not the hub?

Random11

No, not sure. I don't know where the noise was coming from.

oldbobcat

Well, I've never heard spokes make a vibrating noise. I've heard pinging noises, but no vibrating noises. I have a hunch it's something wrong with the hub, something you probably shouldn't be messing with without more expertise and a set of cone wrenches. Take it to a shop. It will probably be less expensive than you're afraid of.

cpach

Ideally all the spokes on one side should have similar tension. Do you have a musical ear? Within a semitone is probably OK, though when I build wheels I shoot for tighter tolerance than that on average. It's pretty common for low and mid end factory built wheels to be fairly unbalanced. If the wheel is fairly over engineered it might be fine, but it increases the chances of spoke failure. If you want to learn about wheel building it can be good practice to equalize tension, but I'd recommend having a truing stand, and possibly a spoke tensiometer depending on how good your relative pitch is.

Geepig

In these situations a shot of your bike can help, as we cannot visualise what you have bolted onto your machine. For example, many years ago I had 'sport' mudguards and on certain road surfaces were prone to humming.

Come to think about it, last weekend I cracked the undertray under the front fender on my car, and that made a sound just like coolant spitting on a hot exhaust while driving at low speeds.

Random11

Thanks to all who offered suggestions on the noise I was hearing. I think I've figured it out. Yesterday I noticed my bottle cage was loose. I tightened up the bolts and rode today and didn't hear the noise. It appears that what I was hearing was the loose bottle cage rattling.