I am comparing my 2005 XB12R with Ferris' 2008 XB12R on the same trip together so the speeds and conditions are pretty much the same. The trip was 160+ miles. My bike has the scoop. On the occasions we stopped, either at a traffic light, stop sign, for food, for fuel.... OK ... you get the idea ... My fan did not run or ran for a noticeable amount of time shorter than his. This happened on every occasion. I notice no negative effects so far. Installation took about 10 minutes. Looks cool and work!!!!