i bought my bike while i was on a consulting gig in San Diego from an independent shop. real good guys. but now i'm back home fulltime in the Bay Area, and am no longer able to get my lifetime free tuneups from them. is it worth paying the $70 to get your bikes tuned up, or can you/should you just do the work yourself? any resources out there on the steps of what you can do to self-service/tune your bike? thanks.