First off, You MUST become your own mechanic. It's not that tough with the help of a good repair manual available at most bookstores. Second, you will soon get the hang of tuning your drivetrain, and forevermore, it will always work really well. Not that LBS tuning is bad, but you can adjust it whenever it gets even slightly off. Third, the money you save on LBS work will pay for the tools in no time. Fourth, if there is trouble on the trail, you will know your bike intimately, and most likely, can do a limp home fix right there. What could be better than that? bk