it looks like the new 790 with R4 tires front wheels have a wider front track than before i would like to find a part number and a source to buy from . mine is an 2004 and is the narrow trac.
Have you rotated your front rims? Maybe what your seeing is a 790 with the fronts rotated already...I rotated mine and left it that way....I like the wider track.
i havent turned mine around i was afraid it might be too much , it does appear the new 790 comes with a new front wheel that widens the front trac. i was hopeing someone had the new ones and could get a part number.