Hey everyone, I'm new to mountain biking and have just received my '09 Specialized Hardrock Disc... I bought it used, though it's pretty much mint. I was thinking I would for sure take it for a tune up, now I'm wondering if it's at all necessary as the chain appears to be pretty lubed (hands got dirty real quick ) What my question is, I put on the front wheel and back wheel successfully from what I can tell. The gears work and the wheels spin . My problem is the back wheel doesn't seem to be spinning completely straight, at one point during it's revolution touching the brake pads... The front wheel spins fairly straight but rubs as well. Should I just leave it to the "pros" to fix my concerns and relube the hardware just in case or should I try and figure it out myself? I mean there can't be too many way to put on a wheel, so I doubt that is my problem. Any input is greatly appreciated!