Aside from all the obvious risks of riding your bike close to any large semi, sometimes unexpected things happen that require you to react quickly.
What we have here is a perfect example of such a case in which the unpredictable happened, and could have caused a lot of harm to the guy on the motorbike, who by the way, doesn’t look like he’s wearing a lot of safety gear – no gloves generally means no jacket & pads.
Even if he was decked out from head to toe in protective gear, he still would have needed to react as quick as he did in order to avoid the debris, which otherwise may or may not have impacted the bike directly.
These types of narrow motorways are often treacherous for riders, especially when surrounded by larger vehicles. Of course, we’ve seen plenty of accidents involving motorcycles to know that it could have been much worse than getting hit by the remnants of a tire.
On second thought, just about any object that might cause you to lose control of your bike should be considered extremely dangerous. Even styrofoam debris – which brought down a group of bikers on a highway a while back.