As is usual on this forum, The OP was immediately attacked by the bikers on the forum. Clearly, those that responded on this thread DO NOT KNOW when lane splitting is
technically legal in SA.
It is thus legal only because it is not specifically prohibited anymore.
The best reference available is this one
https://arrivealive.co.za/Lane-Splitting-Advice-and-Guidelines-for-Bikers-from-the-Experts
There is NO justification anyone has (biker or other car owner alike) who damage another person's property, and if it ever did get to a Court of Law you would all lose and be found guilty.
The "rules" that make it technically legal to lane split are very clear, and travelling over 50 km/hr is not one of them! You could be found guilty of reckless driving.
There are no special rules for 2-wheel vehicles. The rules are the same for all. Bikers are NOT allowed to drive on the line designating the boundary of a lane.
They have to remain within a lane. Just like bikers, drivers cannot always see everything that is happening around them on the road. The onus is on those at the back of a vehicle to always take evasive action as they CAN see what is happening in front of them.
So OP has very right to be more than a bit upset by what happened this morning, and equally completely aggrieved by having is mirror taken off.
He took every precaution to try and mitigate what was happening in front of him.
The rest of you who tried to defend and justify the actions of the biker, are all just plain WRONG!