i just bought a nishiki bike from the thrift store, problem is, i'm pretty clueless about bikes and my rear derailleur is crunched up into the spokes (a friend of mine figured this one out for me!). i'm not totally sure what to do now, since i just got it and don't know much about bikes, anyone with experience with nishiki's would be a great help! how to do i figure out how many speeds i have so i know what kind to get? (seriously, i'm really that much of a noob). i'm a college student, so if anyone has tips on where to get a really cheap one that will work for just riding to town and such, that would be awesome as well. thanks!!!