Hey guys im pretty new in customizing my Streetglide, put some money in the paint and bunch of add ons and now im wanting to upgrade like alot of people are talking about to a 21in front wheel! I have a few questions that I couldnt find answers to in the search 1. If i upgrade 21in in front can I keep stock size in rear? 2. What is the diff between say 21x2.5 or 21x3 or 21x3.5 what does that mean I see the different sizes in all the rims Im looking at. please explain thanks guys. Im an average sized guy 5'10 190lbs. so which size would be best of the above mentioned.