Chain suck!!! that's definitely it! It's only recently that I got into multi-geared bikes so it's new to me. Should I file that "split" tooth on 1st gear and try it again? or just take it to a shop & get their opinion? the odd 2nd gear teeth may be normal as I saw others that looked like it. also there seems to be a lot of slack in the chain, should I take out a link or two?