Another Jetting ? which to use?

[GearHeadz400ex]

well it looks like I will be getting my new exhaust this coming week sometime. So i'd figure I'd ask you guys which jet I should use... The exhaust is a ct racing slip on, the bike is pure stock except I might take the lid off if that would even help any/wouldn't hurt anything either. the 3 main jets I am getting are a 160, 162, 165. Elevation is somewhere between about 600 to 1000 feet.
Hope you guys can help me out.

Thanks in advance.

[Honda#4]

Definently take your lid off cus that lets more air in and gains you throttle response. Are you running with an high flow air filter? If not then those jets will be to big for your setup, I would start with a 155 and then go from there.

[GearHeadz400ex]

so if i get a k&n filter and took my lid off i could use say the 160?

[Honda#4]

You could try it but I think you might need a 158 main.