I just ordered a Big Gun Evo R slip on exhaust for my 2007 400ex, will I need to re-jet my carb after installation?

 

yes you will. before re-jetting i would add the k&n air filter and lid filter so you only have to do it once.

 

jase is right man,if you put that slip on without doing your intake,gonna run like crap,then you will have to rejet after you do the intake. do it all at once and do get the lid filter,should sound sweet when you get done though....

 

if you dont have the k&n filters yet, motorcyclesuperstore.com has both on sale. regular k&n is 51.99 part# ha-4099 and the k&n lid is 110.99 part# ha-4099-t.