I was wondering if I will need a jet kit on my 02 WR426 when i put a stock YZ pipe (slip on) on? My bike has the grey wire mod, twin air air filter, zip ty fuel screw, yz throttle stop, and that's pretty much it for the engine mods. It runs fine with an open wr pipe and a gyt-r insert. Will I need a jet kit? If so, which one is the best for the $$?