I need help jetting my z400

[z400rider03]

I just got a z400 about two weeks ago. It has a k&n air filter and a yoshimura slip on, without a baffle, spark arrestor and padding. When given gas, it bogs down and pops. Can I just adjust the fuel/air screw or do i need a new main jet?

[derekhonda]

Go start it up, let it run for 15 seconds, shut it off, remove your spark plug, tell me what it looks more like.

White and chalky.

Tan and creamy

Black and wet.

[yamaha250f]

Originally posted by derekhonda
Go start it up, let it run for 15 seconds, shut it off, remove your spark plug, tell me what it looks more like.

White and chalky.

Tan and creamy

Black and wet.

sounds like the three girls i hung out with last week. :devil: