its an 03 wr 450 with (not sure on gearing) but it is drastically smaller then stock. I'm going to guess around 44 tooth rear sprocket and a +1 or +2 counter sprocket. I'm currently at college so i cant go look at the bike right now.Can you list some info. on the bike? I'm about to get it inspected and registered then hopefully 17's will be in the near future. What kinda gearing are you running?