Can I run no lid?

[honda_runner]

Can i run my 400ex without the airbox lid? Does it run my motor too lean?

[team_450_88]

It will be alright..might need to adjust ur jetting and I would keep a close check on my air filter and keep it clean and if it is a really muddy ride put that lid back on !!

If you remove the lid you HAVE to rejet or you'll run the motor lean and it will seize eventually..:cool: don't do it if your not going to rejet..

[TC426EX]

Yeah, rejetting is MANDATORY when removing the lid. If you are gonna remove the lid, call up Nac's and get an Outerwears air box lid. It is just outerwears material that velcros over the top of your airbox. It gives the same performance as running no airbox lid but gives you an extra level of filtration and protection against debris. I run one and love it and its only like 17 bucks if I remember correctly...