Found this on some random website...
"Most tires will have a diagram on the sidewall that tells you the tread direction. In general the knobs will have a pointed side and a scooped side. Just think the knobs point forward as a good rule of thumb, although some tires are designed to run the opposite direction on the rear wheel or both wheels."
Although, if you really wanna know, Cheng Shin tires is the same company as Maxxis, so I s'pose you could email
Maxxis.