[Water Warrior 2]

The dealer more than likely put in a 10-40 dino oil. Just for the fun of it why not try 15-40 Rotella dino oil and observe the results. I probably haven't subjected the Vstrom to real high temps like you will have but the bike seems to shift very well in the mid 90's F. No hang ups or missed shifts ever. Lynda's M shifts just dandy too.
If there is no significant change after 1000 miles then bite the bullet and go for synthetic. It will withstand high temps much better than a dino in most cases.