I ride a pretty standard Trek 1000. Got it in 2003, started out real slow (first bike), but am now riding around 100-175 miles a week. I've never had any problems with the wheels, spokes, or really anything mechanic with this bike, until this past month.

I've broken 4 total spokes within 300 miles of riding. As far as I can tell, they're all different ones, and all on the rear wheel. I'm not really sure what the cause of this is, it's happened mid-ride. I don't know much about DIY mechanical stuff (although I'd like to know more) so I've taken it to shops to be fixed. I don't have a problem replacing a spoke every now and then, but this is starting to get ridiculous (ridiculously frustrating). Is this the result of just cheap wheelsets (Alexrims AT450)? Poor repairs at the shop? Or After a couple thousand miles, are wheelsets just something that need to be replaced completely?

Thanks for any help.