Does anyone use plastic air filter cover?

When i recently bought my exc 450 the previous owner told me that before you wash bthe bike down, you take the foam filter off and you put the plastic cover on in its place.

However when i looked in the hand book it says nothing about doing this. In one diagram it actually showed it being placed over the foam filter presumably you leave it on all the time.

I never use it, can anyone tell me what its for and when its used? :excuseme:

I use one all the time. Don't have to worry about getting anything in the intake.


The plastic cover I have does not seal as good as the filter. It will move around and if bumped I will have a open hole to the carb and not know about it.

I did not buy it to use when I wash the bike and will not use it as such.

I purchased the cover that is held in place with the retainer that holds the air filter.

Although it has a soft rubber seal, it still does not prevent a gap allowing dirt to get in the air intake chamber. Not Good. I no longer use it.

If you race or ride in a lot of dust and mud, I would recommend leaving the filter in place while you clean the bike. Thoroughly wipe the air box down with the air cleaner in place making sure you get any grit or gunk off that could drop into the intake chamber when you pull the dirty filter. Pull the dirty wet filter and install a newly oiled filter with each ride.

I purchased a second filter screen and a dozen new filters. I oil the new filter and mount it on the filter screen. Apply No Toil filter sealing grease when I pull the old filter I immediately install the new filter. I feel the longer the air chamber is exposed without a filter the more likely a spec of dirt will get in there. My opinion, but if you are pulling the dirty filter to put this cover in place, then cleaning the bike followed by removing this cover to install a new filter, you are doubling your chances of getting dirt in the intake chamber.

The system:

If you purchase several filters you can get them for less than $20.00 from just about anyone and then the day you change your oil you can clean a group of 5 or more to set aside to dry and reuse. It’s a dirty job, but this system keeps you out of getting your hands dirty every filter change!!! I clean a batch once a month and always have clean filters oiled and sealed in a breathable zip lock bag ready for a quick change.

Nothing is more critical than keeping the air chamber and air box perfectly free of dirt and grit both while you ride and during filter replacement.

This is the time to have a surgical type process to keep that top end like new.

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