I've got almost a 1000 miles in on mine and I'm seeing a trend of lot's of heat buildup in the motor on slow, tight singletrack riding. I've had the cooler fan kick on like mad on about 5 different rides now. Most of these have been up under the trees or early mornings. I'm starting to think the single side radiator just isn't up to the task, hate to think what it would do down in the desert. I kinda wish that Yamaha would just have gone with a second radiator wing and lost the high tech sensor/fan setup. If you're ever out lugging it in the heat and that fan dies you're screwed.