Noisy rear gears

David Glover said:

Disclaimer: I am a very non-pro cyclist and will probably now proceed to use
all the wrong words for things.

I have a Dawes Kalahari hybrid which gets me to work and back every day,
five miles but with some fairly steep-ish hills in between. (Up and down, so
sadly in both directions. Bah.)

My rear gear has seven positions. Where 1 is the slowest and 7 is the
fastest, there seems to be something funny going on with gear "5". Whenever
I'm in that gear, I can hear a fairly loud rattling or tinkling sound coming
from the rear cog. It still seems to work perfectly well, it's just noisy.
It's worst when the front gear (Slow 1 - 3 Fast) is on the fastest "3"
setting.

It's recently been into a local bike shop for a routine "Look at my bike and
fix anything that's broken please" visit, and they didn't find anything
wrong, other than the chain needing oiling, which they did.

Should I be worried? Anything I can fiddle with?

It sounds like the indexing needs adjusting a little. Probably
nothing to worry about and you should be able to fix it yourself. See,
for example, <http://www.sheldonbrown.com/derailer-adjustment.html>
for detailed instructions on adjusting your gears.

David Glover said:

My rear gear has seven positions. Where 1 is the slowest and 7 is the
fastest, there seems to be something funny going on with gear "5". Whenever
I'm in that gear, I can hear a fairly loud rattling or tinkling sound coming
from the rear cog. It still seems to work perfectly well, it's just noisy.
It's worst when the front gear (Slow 1 - 3 Fast) is on the fastest "3"
setting.

It's recently been into a local bike shop for a routine "Look at my bike and
fix anything that's broken please" visit, and they didn't find anything
wrong, other than the chain needing oiling, which they did.

Should I be worried? Anything I can fiddle with?

Was the noise there before the shop checked it over?

Just a guess without looking at it, but is there some lateral play in
the cassette (the cluster of 7 sprockets)? Normally the five largest
ones are riveted together and the other 2 are loose, with a very thin
spacer between them and the bigger 5. It's possible to get a bit of
play in them; it may be less than a millimetre but it can be enough to
produce noises such as the ones you describe. Test by putting your
hand inside a polythene bag (to keep it clean), grasping the sprockets
through the bag, and pulling in and out. There should be no lateral
play.

If there is play it's probably not important if your gear changing is
not affected and you can live with the rattling. The cure is either to
tighten the special nut that holds the cassette on, assuming it's
loose, or to fit another thin spacer behind the cassette. Your shop
can do this for you for a very modest charge, or more likely for
nothing as they've just had the bike.

--
Dave...

Get a bicycle. You will not regret it. If you live. - Mark Twain

"Dave Kahn" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Was the noise there before the shop checked it over?

Yes, and in fact when I got it back the noise had gone away, but came back
again after a day or two.

Quoted message said:

Test by putting your
hand inside a polythene bag (to keep it clean), grasping the sprockets
through the bag, and pulling in and out. There should be no lateral
play.

I'll try that tonight, thanks.