Having finally gone and cleaned my commuter bike, it has developed a mystery squeak.
It happens when I go over bumps, I think from the back wheel.
If I lift up the back wheel and drop it, without the wheel turning, it makes the same squeak.
It sounds sort of like air being squeaked or something, quite high pitched. The wheel has no play in the hub, tyres are pumped up fine.
I have mudguards but I don't think it's a mudguard noise.
Any ideas what it might be?
trapped mouse?
Hmm, it didn't go for my cheese sandwiches so I'm guessing not.
It is weird, can't work it out at all, only happens when the back end is sharply dropped.
You need Mr Fix-It.
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a loose spoke perhaps?
No obviously loose spoke on the back wheel, but I might try going round with the spoke key, the front wheel had a loose spoke (or 5) which I fixed, due to a wheelbuild I did about 9000km ago finally coming slightly loose, but that wasn't where the noise was coming from. The back wheel is only 2 years old, although I didn't build it, so I don't know how good it is.