well, i got a spare walmart bike hanging around here. i'm wondering if it's worth putting time and effort into upgrading the thing to make a decent commuter...the only big problems with the bike are the front fork, and the brakes. the biggest thing i'd probably have to do would be upgrade the fork, because let's face it, the stock one sucks (bobs up and down while i'm pedalling). somehow, while taking the brakes apart, i lost 2 of the springs, so i'd have to replace those too. ultimately, i'd probably wind up keeping just the frame, cranks, and rims and replacing the rest. but, is it worth it, or should i just put all my money into a brand-new setup?