yup, squids always like to make noise, specially on a cold engine or at 12 oclock with the engine starving for oil, why I wont but a stunt bike and learned what to look for in used stunt bikes
look for bits of rubber anywhere around the rear wheel, it gets into odd places after several burnouts...
look for the fender hitting the nose plastic
look for evidence of the rear shock bottoming out excessively
scoured fork legs at the rear of the tubes, they will rotate them so just look for scouring, stoppies put a lot of pressure on the insides of the legs
look for lots of wear and tear on tire change hardware, axle bolts rims and so on, stunt bikes tend to go through lots of rubber, I bike with 12,000 miles shouldnt have any more than 3 changes rear 2 in front, stunt bikes tend to lose wheel weights as well..
theres the obvious stuff as well, evidence of dual rear calipers cages and so on..
some stunters are cool and simply say hey, this was a stunt bike, others try to pawn them off as "mostly highway miles"
not much you can do about dolts int he video that just don't have a clue period, know what it should ride like and ride it.
but yea that guy shouldn't be allowed to own a bike, and don't ask me why I went off in a tangent, I dunno? I just did