I believe I have found away to make an inexpensive radiator protector using something called an under eave vent found at many hardware stores and home improvement stores($2.39 @ Ace Hardware in Springfield, IL) . The vent already was the exact size as the radiator on my DL650(16Ēx 8Ē) making it a bit snug, so I bent one edge over with a pair on needle nose pliars and it fit just fine. The stuff below it is called hardware cloth and I used it to reinforce the guard after I zip-tied it onto the radiator. The picture below was on taken on the wooden boarded floor walk outside my apartment.
Undereave Vent - Cropped.jpg
There was some trial and error, figuring out where the zip ties would go through those gaps near the radiator tank and through the guard. I used a nail to punch holes in the hardware cloth & vent for the 6 zip-ties to go through-when I had off the bike, of course.
Radiator Guard Mounted-cropped.JPG
Iím not saying it will stop a .45, but Iíll bet it will stop some decent rocks & large bugs, and I havenít experience any overheating problems. Some undereave vents that others may not have the fins cut so far into the center, though. Whole thing costs $5-$6 and didnít take that long to do, either. I feel better having it on there.
There's also a similar vent which probably could be used to build a guard for the oil cooler, but I chose to just use the hardware cloth on it since I already have a heavy skid plate protecting it(Adventure Motostuff) and didn't want to inhibit the airflow around it any more. Hope this helps someone else.
P.S. I'm sorry these pictures are so small, but I'm still learning how to edit them down to meet the size guidelines for this website. I'm using a 2.0 megapixel camera then cropping or shrinking the image size down using adobe Photoshop. I would appreciate any suggestions as I may post some other penny pincher ideas I have found.