Paul,
Boy do I have a fix for you. If I had read your post before lunch, I would have taken a few pictures to post.
Like so many other KX500 riders, I, too, lost so many radiator louvers that kept a spare set in my van (oh yea, I posted a couple of pictures of the inside of the race van this morning). However, in the middle of the night, my brain found a solution (I hate when this happens, as I have to get up and draw pictures in order to remember. I designed an all steel tilt front end like this several years ago, all in one night. Ugh!)
I picked up two pieces of stainless sheet, maybe 1/16, about 1 inch wide, and long enough to extend from just past the top and bottom radiator shroud mounting bolts. I removed my shrouds from the bike, held the little plate on the edge of the radiator so both mounting bolts were covered, and marked the holes from the front side of the radiator. I drilled these holes just larger than the standard radiator shroud bolts so the bolts could pass through the holes into the little weird nuts on the radiator mounts.
Next, I drilled two holes evenly spaced in the middle of the bar, mounted the bar to the radiator without the shrouds, and drilled into the louvers. I installed two bolts to hold the louver to the bar, and then installed the shrouds which holds the bar in place on the radiator tabs. Viola! After a year of hard riding and racing, not one louver lost.
The only problem now is that my louvers last so long, they get looking a little drab.
Hopefully my explanation is good enough to follow. If not, maybe I can snap a few pictures.
In the past few days, I have also welded three nuts on my pipe to secure the pipe guard, and repainted with high temp paint. While I was at it, I sheared two pieces of 3/16 aluminum, and cut out two pieces of high impact plastic stuff to make a new, stronger chain guide. Mine was in pieces after hitting something (not sure what, as I did not even know it was broken until I washed my bike after returning home
), so instead of spending $30, I spent a couple hours in the garage with big green. Too much fun...
Rick