help a n00b figure out what this sound is

[Madkour]

So i've been riding my new bike for two weeks now and i've been very happy. i've had new tires put on, an oil change, and a general inspection just to make sure everything is in good order.

Just today i noticed a kind of high pitched rattling sound coming from what i think is the rear tire area. it comes and goes usually above 30mph, and it sounds almost like a chain being dragged on the ground. anyone know what this could be?, or if i should worry about it? i've kept the chain lubed, and its pretty new too.

sorry if this is something i could have looked up, but i dont really know of any standardized way of describing sounds that i could have searched.

[cummuterguy]

did they adjust the chain? i once had a noise like that, found it to be where that big square washer is on the back of the swingarm, wasn't quite tight agains the swingarm (there are two of these)  apparently, I has adjusted the rear tire where it was correct, and the chain was tight, then tightened the rear axle back in place, but somehow, that washer wasn't quite snug... i re-checked the alignment and chain slack, it was ok, so I just tightened the nut on the adjuster stud til the washer was tight... no more noise
only thing I can think of... hope it helps

[Richard UK]

Check that the bolts retaining the sprocket on the rear hub are tight, also that the rear brake caliper has not worked loose.

[stephan]

A very loose chain will drag on the center stand while driving.  It makes a sound like, well, a chain being dragged over a piece of steel (shocker I know   )  You may want to check into that.