Advance Auto also has those filters in differnt colors.

 

The crankcase vent is to let the air pressure equalize when the piston goes up and down.

When the piston goes up, it draws air into the vent. When it goes down, it pushes air out of the vent. Without the vent, the air would have no where to go and would most likely find its way out of a seal or something and create a leak.

From what I have read, the vent doesn't generally need a filter because the air volume isn't enough to fully go into the crankcase. It just sort of pulsates in the hose. Even from the factory, the vent is not filtered since it is just in the snorkel.

Even though it may not need a filter, I always ran one on mine, just in case. Figured it can't hurt.

 

cool slappie..now i feel better

 

True, the hose is not pulling in enough air to warrant a vent, but that's not why you put one on. You dont need negative airflow for dirt, dust, sand, and water to find its way into that hose, even when the bike isnt running. The filter is to keep things from coming in no matter if they were sucked in or fell in. Thats the same premise behind putting the hose in the airbox, to keep things from having a direct line into the hose and eventually the engine.

 

Check out my photo page.

 

I picked up one of those for my machine too, works great with the adaptor, thanks.[img]i/expressions/face-icon-small-smile.gif[/img]