Originally Posted By: frankge
I switched to Mobil1 which is supposed have a better based stock. TopSpeed is a group III and the oil looked pretty good when I changed it. Going to stretch it to 4500 this time. I use a K&N oil filter with neo magnets. I'm not worried about the shear, I wont run a 50wt even in Florida. People run heavy oils because the "if two aspirins is good 3 are better" syndrome. This is a water cooled bike and I do run it pretty hard at times, my previous monster was air-cooled, I ran 50wt in that.
Tops speed is a groupIII, and you belive mobil1 is a group Iv?
One key note, Mobil1 mc oils, used to have a lot higher flash points years ago, the base oil aint the same.
As to your 50 weight comment, add 1 quart of 50 weight in your favorite 10w40 brands, and you'll have a better chance of holding 40 weight.