03 z400

[mxracer11]

i have a 2003 z400 with a white brothers full system and the airbox lid is on but everytime i get high rpms it bogs out and acts like its flooded.does that mean i need a jet kit or what?

[John Noftsinger]

Did you just put pipe on without jetkit?if you did then yes you need to jet it .if pipe was on when you got it, you will probably needs to be jetted better maybe the guy didn,t switch needle/pilot jet and you could be at different altitude aswell and need to jet for that.

[mxracer11]

i got it from sombody i know and he just put the pipe on befor i got it and it is the stock jetting.so thats why its bogging out is because i need a bigger jet?

[miles Machine]

yes most of the time you can get away with the stock pilot but if it starts to back fire on decel then you need to bump it up and honestly moving it up one ne ways would be good insurance.....i would get a aftermarket needle that way it is adjustable, now you can use the stock needle and just shim it but that can be a pain in the *** with the aftermarket one start off on the middle groove.......for the main you have to be sure what kind of jets your getting, if you get a kit like dyno jet the sizes are different that what mikuni goes by and ive sen ppl burn engines up because of that so i suggest sticking with stock brand mikuni jets...stock is 130 id say go to a 140-150....now for your fuel mixture screw lightly seat it then turn it out 2.5 turn you should be after that

[mxracer11]

so what size pilot jet do i get?

[miles Machine]

25