Ralf, it is really quite easy to calculate how fast he was going.
The lady looked like she just came out of a 7-11 so we can calculate the average length of a store front of 7-11's in Patong.
We know the make and model of the white car that drives through the frame ahead of him so we have the dimensions of the vehicle and can easily calculate the speed it was travelling as a benchmark for all other vehicles in the frame.
Looking at the clip we can see the guy in the yellow T-Shirt is walking at a very casual pace so we can calculate how fast he was walking.
We know the make and model of the bike the "gentleman" in question was driving so we have the dimensions of that.
Putting all the above evidence together we can make a fairly accurate calculation of the speed he was travelling.
It was TOO FXXXXXG FAST.
Happy now?