ok I am looking because in my research on my bike Cobra who now owns kerker states that rejetting is needed on my bike for the f1s exhaust ( which is on there) so my question is I see 3 diff kinds of kits (not manufacturers) I see the 10 recalibration kit, the stage 1 kit, and the stage 1&3 kit could someone explain how this is figured I mean i understand that it is different size jets but is 3 smaller than 1 or what please either direct me to where I can find this info or give a brief explination. I ask because I am looking to order new exhaust and would like to re-jet because I do feel that is one of my probs. but first I want to test the carb sync'ing. my seat of the pants is telling me that compression is fine. waaaaayyyyyyy too much pull to have a compression problem. oh yeah BTW the bike has alot more livelyness since I cleaned the carbs and adjusted em and put in new plugs. thanks for all the help and advice guys and gals.