SeerAtlas, Only on some of our bikes (coolers). It's all about the temp of the oil and we can somewhat control it when waiting in line. You want the perfect oil temp when you take off at the line, but you never get perfect temp most of the time.
mjstef, Mobil Delvac Elite 15W40 Is a very good oil. Now don't laugh... we use SuperTech from Walmart.
Also we have a few ATVS and motorcycles with the Hawk style engines that we have used for years and we don't have any shifting or heat problems in the mountains or on the flat lands.
