I love single speed riding but would recommend before you do this take your multi speed bike and put it in a gear that is comfortable for you to ride in. Then ride the bike for a month without shifting gears. You may find you do not like it and you will save yourself some time and money doing this. I as I said use a single speed as my knees at 61 just will not take a fixed gear anymore. My second suggestion is you also look at just buying s SS/fixie as you can get into them for $200 and you will have a hard time building one if you have to buy a bike and all the parts necessary. Roger