I havent riden my mountain bike in a few months, after buying a road bike and trainer, Im gung-ho for the spring. Today I bought new tires for the mountain bike. went to swap them, noticed I have a broken spoke nipple. wheel perfectly true. Had the wheels built a couple years ago by an excelent wheel builder. Im 240lb ride an FSR with hayes discs. The wheels are Mavic 517, wasnt expecting them to last, but they have taken tons of abuse. Im thinking maybe the spoke broke while the wheel was off in the back of my bronco. Checked the others, all fine (tight).