990 Filter Skin

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by laramie LC4, Apr 27, 2013.

  1. laramie LC4

    laramie LC4 crash test dummy!

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    since purchasing my 990R in december one of the first things i did was to use a filter skin i had for another bike to cover the snorkel intake to the airbox. i had seen and read about people using the UNI pre-fliter to help prolong the life of the filter but frankly, it looked like more hassle. i have not removed any of the EPC crap and there was no way i was going to be able to cram that filter in without doing so. i also thought the UNI was just adding more work? maybe i'm wrong but....

    i am now at almost 4,000 miles. over 1/2 of which have been off-road in dusty arizona conditions. i just pulled the airbox cover and filter and this is what i have.

    what do you think? since this is my first look at the filter i have no frame of reference for the condition.

    [​IMG]

    and a view of the bottom...

    [​IMG]

    i think it look pretty good considering what i have done on the bike. i was a little concerned about some residue on the primary butterfly valves, but it looks like mostly crappy fuel residue and had no real dirt in it. is this amount of crap normal?

    [​IMG]

    top of the airbox was spotless...

    [​IMG]

    here is pic of what the filter skin looks like when installed. when i removed it you could tell that it was full of dust and had obviously been doing something. the question is....is it enough to make any difference or am i just being overly optimistic????

    [​IMG]

    looking forward to your comments. :ear

    thanks,

    laramie :beer
    #1
  2. knobbyjoe

    knobbyjoe Adventure and dirt rider

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    May we see your prefilter?
    #2
  3. laramie LC4

    laramie LC4 crash test dummy!

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    nothing fancy. just a basic sock pre-filter. i originally had it for a cylinder shaped (3.5 x 6) filter that i was gonna use on another bike. here is the best pic i could find HERE. it is part number 20-1049-01, i believe it came out of an atc250r, but for some reason a search on their website returns nothing? i'd take a pic of the actual filter but it already back in the bike.

    laramie :beer
    #3
  4. laramie LC4

    laramie LC4 crash test dummy!

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    almost 200 views and no responses, guess i need to be more specific with my questions...

    does my filter look; A) dirty, B) clean, or C) just as it should for 4,000 miles half of which was dirt? :ear

    like i said i have no frame of reference since this is my first time looking at it.

    thanks,

    laramie :beer
    #4
  5. laramie LC4

    laramie LC4 crash test dummy!

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    come on guys, your killing me. 270 views now and nobody has any input on this? :ear

    thanks,

    laramie :beer
    #5
  6. The Griz

    The Griz Long timer

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    The bottom looks super dirty to me, but just as it should after 4,000 miles of mixed dirt, gravel, and road. The top looks good. Your airbox looks spotless, so things are doing their job. Hard to say if the filter skin is doing any good. How does the filter skin seal around the intake snorkel? Some dust could be getting in around there maybe? I have to say I do recommend the Uni prefilter. Seals well and keeps out a lot if not all dust. Cheers.
    #6
  7. DesertSurfer

    DesertSurfer Tail sprayin

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    It's hard to tell in your photo just how dirty your filter is... But it does look dusty. And it's meant for 1 cycle... So I'd chuck it. But the direction of filter choices is leaning toward reuseable. The Uni pre filter left my main filter minimally changed. I have since added PC Skins prefilter skin and DNS reuseable filter.

    I may go with a Uni filter when they come out with one for the 950 like their 990 version.

    With my current set up I can simply swap out a pre-filter skin if it warrants after a long 2-300 mile dusty section and my main filter is still clean. I've ridden 1000 mile trips on a couple pre-filter skins and afterwards just cleaned my pre filter, while my main filter was still very clean.

    It maybe overkill... But it's extremely easy on trail service. And minimal replacement expenses ... No OEM air filter.
    #7
  8. slackmeyer

    slackmeyer Don't mean sheeit. .

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    Again, hard to tell from the photo, but I'd run that for another go around, that's partly because I'm cheap. But it does look like your filter skin is doing a good job on the larger dust particles but letting plenty of fine dust through. paper filters are really good at filtering dry dust, I wouldn't worry much about the filter passing silt if you used it again. I've had my filter really caked up with silty dust and still had a nice clean airbox top and an engine that was just down a bit on top end.
    #8
  9. laramie LC4

    laramie LC4 crash test dummy!

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    thank you guys. that was what i was looking for. i knew that the really fine stuff was getting through, as expected, but my thought was the skin was keeping the majority of larger stuff out. it just added another barrier to help filter, was cheap, was really simple to install, and was hopefully pro-longing the life of the filter. i may look at the uni filter again, but like i said i would need to remove all the EPC stuff and im not sure i'm ready to do that yet.

    thanks again,

    laramie :beer
    #9
  10. Boatman

    Boatman Membership has it's privileges ;-)

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    To see what the filter is doing exactly, spread the pleats and see what's in between. That knife edge will get dirty within a couple hundred miles.
    #10