Radiator fan. There wasn't much space on the left radiator and even less on the right so I decided to balast down the left side of the bike a bit more. The fan will just bearly fit under the return hose and in front of the head. You can't see but there is a small fold/lip on the inboard seam of the radiator similar to the one just above my thumb in the photo above. I am using that lip and the mounting screw that was used to secure the DRZ plastics to hold the fan in place. Start by cutting a sheet of 16 gage and folding two 90s in it to make it stiffer. I forgot to take pictures for a bunch of steps. I cut a notch in the two upturned edges and folded a 90 in the main sheet. I drilled, punched, and notched an opening for the fan and its mounting screws. To keep the mounting screws from digging into the radiator, I recessed the mounting holes. I did this by using a socket as a die, and a chisel as a punch. I blunted the metal chisel cutting edge and flipped it around. I pressed it into the piece by hitting what would normally be the cutting edge and using what was the handle as a large tool steel round punch.