I installed a Power-bomb Header and a FMF Q2 recently. I had some work done by the local Zook shop and the mechanic told me the bike ran great and did not need Jetting. Since, I have been having some sloppy throttle response and it seems to bog down before the power hits. I am also having problems with the kick-start, it is very hard to start (I am not sure if this could have anything to do with the Jetting so please don't slaughter me on this one... ). If it does need Jetting, what would be recommended? Thanks. 07 RM-Z450, Desert/Trail Riding, Occasional Dune Trip. Range from Sea Level to 5000 ft. I will have to look up the stock settoings, I'm currently at work and don't know off hand. Hope this makes things a little bit easier.