Ok. I love my singled speed trek now and I want to make the change permanent. I know I need to buy a tensioner (right now I am using me rear derauiller) I know I need a new rear cog(cassette I don't think is unassembleable). But My question is can I use the nine speed front chainring with a 1/8 rear bmx cog and a 1/8 chain? Or will the extra side to side chain slop damage the front chainring? Any replies are greatly appreciated.