Just about every MC tire I've ever replaced (thousands) is wore more on left than right...like yours. I read an interesting explanation that because we here in the US ride on the right hand side of the road, the longer distance around left hand corners accounts for tires wearing in this manner. Over the life of the tire this logs more miles on the left tire side. Is it true?...not sure. It's also common for wear not to be exactly even all the way around the tire. When checking wear, it's a good idea to rotate the tire 360 degrees and gauge the condition of the tire based on the worst wear, not the best looking part. BTW, you probably realize it, but that tire should've been history a long time ago.