All of the sudden my front sprocket is making a noise. It is non-specfic, sounds like it is turning, but loudly. This is my 5th year with this bike and it has never made any noticeable sound. Even the guy I ride with said it was different than he's ever heard. I hadn't rode in about 3 weeks (vacation then broken foot--and still shouldn't be) and tried it last night and this is when it started. I oiled the chain right after the last time I rode. Someone told me the rubber seal around it may have become loose. Any ideas??

 

Pull off the cover and take a look at it. put the bike up on the stand and spin the tire with it in neutral. If you still can't isolate the sound, then depending on how good your stand is you may want to run it through the gears and try and listen for the noise.

One tip, if you decide to run it on the stand, put the front wheel against a wall. That way if it comes off the stand it will probably just burnout then stall. If your stand is the least bit shaky don't try it.