When is it ok to run without an airbox lid, assuming a filter and prefilter are being used? Dunes, Mud, Dirt?

 

Hmmmmmmmm....I wouldn't run without it if there were any chance of water, mud, rain getting into it.

 

But dust and sand are ok as long as theres a prefilter?

 

If there is any mud/water possible on the ride, you need the cover. Dunes you could skip it if running K&N and prefilter, but sand doesn't play as well with foam so I would still run it. The opposite tends to be true for dusty conditions, where I would rather have a lid for the K&N but would feel somewhat comfortable with no lid and a Uni.

Then again, I always run a lid with the Uni 1" filtered holes for more flow and keeping the protection. Alternatives would be some of the new Outerwear and Mo Flow lids. Dirt, water, and dust will kill an engine in no time, I prefer to keep mine pretty protected over adding a couple of HP.

 

NEVER! a guy I ride with accidently left his off his sportsman 700 when he was in a hurry to get going and the ATV ran horrible! it loads up waaaaaaaaay to much with air and it will just spit, sputter, cough and everything but run smooth. I wouldn't do it but whatever makes you feel good! Why would you take it off anyways?

 

I ran an open air filter in dust and sand with K&N for years with zero issues. If you get a performance pipe and rejet, its the only way to go imo.

 

Just me, but if I was to put anything on my atv without a top, it'd be the one in pink.

 

LOL! Hard to argue that!

After tearing down the mini after running a K&N open right behind the front wheel, it got sprayed all the time, I'm convinced they filter just fine.

 

I'm one with pink-

what was the OP's question again?






oh ya, and "I hate massachusetts"

 

If you rejet it properly you can run without the airbox lid in all conditions.
If you don't rejuet you will run way too lean and will damage your engine.
I use a well oiled Uni filter on my quad and run sand, dirt, water and mud with no problems without the lid.
You just don't want to submerge the airbox in water.