I have a 2002 xr400 I want to trail ride with my son and supermoto with myfriends. First: gordon mods, would 160M and 60P jetting work with k&n, snorkle removed, and 3 holes in muffler. I ride in ky at 200 ft elevation. Second: I got sumo wheels from warp 9 and want to be able to swap street and dirt wheels easily the chain that I have now is long becuase it came to me with a 14t front and 148t rear. I have now a 16t for the front and 44r rear. Could I keep the chainn length the same for my two setups if I got a stock 45t for the dirt rear wheel, giving me 16t/44t street and 14t/45t dirt combo setups. I think I can use the same chain for these but can anyone confirm that these gearing setups could share the same chain? lastly, it seems the stock chain guide slightly contacts my sumo wheel, anyone know of a thinner option or I may just grind a little off. thanks so much gurus.