Originally Posted by SoCaled

As others have said above this site is a great place for info. One pro tip is to use google for your searches but include bikeforums.net.
Try google searching "Trek dual sport bikeforums.net" or pick a part you want to replace "what is your favorite Saddle? bikeforums.net" this will bring you to lots of threads with great info. Another great place to start is threads like "Show us your vintage mountain bikes" which has hundreds of pages of bikes people are showing off, many of which have been upgraded or customized. Take some time and explore. Welcome to the forum