That is very interesting! Yeah it looks like a light 40 weight from what you said. Like I said before, you are extremely informational on oils and I am glad you are here to help!

It isn't very hot up in Michigan, usually between 70's-80's MAYBE 90's a day or two. I talked to a few of my friends and they all run 10w40, one runs the maxima 10w40 synthetic and says it would be fine for my 400ex. I might change the oil before the sand dunes, and do the mix because it is a lot hotter in the sand, than in the woods. Thank you so much!