I'm going to be doing an offroad race next week (Asama GP6- May 4) so decided to get some offroad only tires (non highway approved). Following some research regarding what's currently available and reading various reviews, I decided to give the relatively new Dunlop AT81 tires a go. These reportedly work very well with the Tubliss system at low pressure as they have stiff sidewalls and a softer center section. They are intended to be an all round offroad tire, suitable for use in any conditions. I purchased them online from a store in Rakuten for 14,433 yen delivered. I'll let you know my impressions of how they perform after the race.
Front AT81 (90/90-21)
Rear AT81 (120/90-18)