Do you have the outer filter? I usually oil the inside one like what you showed and leave the outer filter dry. I have gone through a whole race day without changing the filter out on my buggy and truggy and if the inner filter is ok but the outer filter is dirty I just blow off the outer filter with the air compressor and reinstall it. Outwears also makes a filter cover to get rid of the excess dirt going in. I also heard of guys using womens nylons and pulling them over to and tying them off on the neck of the filter.