Certain motorbikes have horns loud enough to deafen an elephant. Generally speaking, drivers want to alert you to them passing. 50% of horn peepings are probably reflexive; the thumb just peeped without a reason. Others will hold their thumb down for a long horn blast. Yikes! There is nothing you can do about it. Don’t take it personally. Don’t get stressed. Just ignore it as much as possible like everybody else around you.