According to the info I got, this happened in Thailand. The video shows the aftermath of a fatal road accident. The motorcyclist crashed, presumably with a lamp post, and died ripped in half.
He was wearing a safety helmet, which can be seen in the footage of his upper half, but helmet doesn’t make a whole lot of difference if you speed like a lunatic. I presume he was speeding because it takes a lot of force to rip a person in half.
Props to Best Gore member @CryBaby for the video: