Motorbike taxi, price raised

[Mann33bkk]

October 1, I noticed that the prices of motor bike taxi went up. There was a notice on the taxi stand, with info that certain sections had increased the price. But two weeks later I became charged 33% more on another stretch it was announced that the price was changed.

Can motor bike taxi just put up the price when they want, or are there regulations governing this?

There is not much to complain that the price goes up a few bath. But it seems they should inform a little better! Although a percentage increase of 30 percent is quite a lot, compared to what you read about that regular taxi should be allowed to increase their rate