i would also throw the shinko 705s into the mix as an option... no direct cross sizes, but you could run the 90/90-21 up front and the 120/80-18 out back i would think with no issues... i have a 130/80 rear on my shineray and theres no rubs, but its also a street tire for a 16" rim... just food for thought....
http://www.shinkotireusa.com/tire/705-series
