i got a 04 z400r it already has a revmax cdi box, k&n, performance wise thats it for now, but i am lookin into either a full yoshi or fmf setup, what else can i do that is cost effective to make it quicker? how do sprockets work? i jsut upgraded to larger tires because the riding i was doing was taking a toll on my skid plates... thanks for any help, i already have nerf bars, full skid plates, rethal bars, scott grips, 4+ lonestar axle, itp, amd douglas rear wheel hole shots on the it's and mudsharks on the douglas black label, douglas red label front, dg front bumper, upgraded steering stem, and few other things here and their...

 

you can have it ported and bigger carbs and cams,valves ,springs clutch,suspension
my shop will port it for you