European plates, so this guy has to have had riding lessons. Or maybe he's riding a bike he's not legally entitled to be riding. Or maybe he's got a non European license.

In any case I'm no expert, but this seems more like an egregious lapse of judgement rather than an innocent accident...

In low gear the rider purposefully added enough throttle to lift the front end. When the front end comes back down the rider inadvertently pulls on the throttle again (you can see a few moments later how his right hand semingly has a death grip on the throttle...). At this point you can see his left hand come completely off the clutch. In fact, his left hand very nearly leaves the controls completely due to the unexpected acceleration. The bike then immediately decelerates presumably from engine braking because you can see his right hand a few moments later isn't on the brakes until the last few moments. Of course they may be using the rear brake. In either case, at that point the rider still hasn't regained control as you can see his left hand is now completely off the controls. In the end they got lucky and crashed into their buddies instead of launching themselves into the busy roadway. The speedo reads 42kph (~26mph) at moment of impact.