Frankie so have I and all the others up where I ride when the bikes made 50-60 hp they don't over heat we also did different hills then now we do hills that there is no runway no fast way down the hill to get air to the radiator.
Take a 10mill cub on the sand do some 300-700 ft drag up the steepest hill you can find stop the second your done and dont slow down, lock the brakes up so you dont get air flow idle for a minute do it again see how many times you do this before it gets hot. It also has to be over 85deg and humid as hell. This is how we ride. This is why I ask has anyone done a fan and if they worked? If we go ride when were done the hill they don't get hot. I would rather let it idle a minute that go ride around on the rocks with my paddles every hill.