In preparation for my Sturgis ride, I took my oil cooler out to clean the debris, and here's a couple of things to note.
First - And most importantly, if the bike is a couple of years old, be VERY careful with the hoses. Mine were stuck, and even very carefully trying to twist them with pliers caused them to crack. The bad thing is, they are on national back order. I figured this out after I broke mine and took a ride up to the local dealer to pick up a new set. He quoted me the end of August! I got lucky and found a set in stock about 150 miles away, so I jumped in the truck immediately, to avoid missing my trip. The moral of that story is, before thinking about disassembling, buy a set of hoses first. these things are preformed with tight radiuses and there is just no way to fab up a temporary.
Anyway, I found the cooler pretty much filled with little pebbles and cottonwood things. Was much worse than it looked as it was all jammed in between the fins. I ended up taking a thinkness gauge and grinding it down to fit the gap, and simply went fin to fin, from the back side forward to push out the crap. Took a hell of a long time, but I was able to straighten the small impact damage and clean everything pretty well.
Upon reassembly, I went up and bought some aluminum screen material and wrapped the front prior to installing the chrome cover. While that won't help a lot with major stones, it will definitely help with the cottonwood and smaller stuff. I'm not sure what else can be done, short of going with an aftermarket unit that mounts higher, or getting a mudflap of some sort.