My '03 gets hot on slow technical trails and will even boil
if not careful to be sure and keep quite a bit of air moving through the radiators.
I added a muffin (computer) fan that I found on e-bay that has been treated so it is waterproof. I even think the company that does the water proofing is still selling them there.
It is 120mm square and 38mm thick, just thin enough that it fits nicely between the tank and radiator on the right hand side. Built a couple aluminum brackets to mount it and it is a nice job rated install.
I believe the company selling them is listed as mynewfan on e-bay. They have a video showing them hosing down one of
the fans after the waterproofing and it is pretty impressive. Mine has so far stood up to LOTS of rain rides and washings as well.
They really move some air...so much that a buddy told me if I was in doubt about making it up a hill I could just kick on the fan and it would help pull me to the top!
I just hooked it in to a push button on/off switch I can operate with my left thumb.
I think I posted a picture on here in another thread in answer to another guys question about them back in the Summer.