Where do I get one! Its one of those new ultra subatomic particle air filters I've been hearing people rave about.
How bad can this be, it depends how long you've been driving without one. Otherwise if you've only thrown a few km on there and been lucky not to take in any hard debris (regardless of size), you should be fine. With the problem of oil in the air filter housing, the dukes are notorious for this. Most of the time its really quite simple...a worn engine, more specific the rings, and there you have blowby. Take a quick peek into the air filter assembly down the long section, just above the valve cover, thats where its coming in from. With the air filter housing completely removed, looking at the valve cover you will see the port. With the motor running see how much air is blowing through. Or just pull off the oil filler cap and you should feel some there. I'd say check the pvc system but in all honesty, its too simple for anything to go wrong and I have yet to see a duke that even needs a pcv check valve, but i have seen a few with plugged breather filters, the little round looking thingy pushed into the valve cover. As long as you can freely pass air through, its golden. I've seen engines with so much blowby and such badly plugged filters, oil was just being pushed right by the main seals as if they didn't exist and blown out under the valve cover thru the gasket. Can you smell it now....
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