On this bike, no matter how much I tighten the seatpost (clincher?) bolt , the seat post still spins, slightly. By that, I mean it doesn't spin around like the wheel on WOF, but it will turn if I get all wiggly while riding. When I got it, the seat post was rusted in the seat tube and I had to struggle to get it out. I lubed it before putting it back in and now I have this problem. A) Did I use too much lube? B) Is the seatpost just a hair too small? I don't know what to do. Let me know if you need a better picture. Thanks.