Fine for not wearing a reflective vest on a motorcycle, how much is it?

It depends on the country you're in, but in most places in Latin America it's somewhere between 50 and 200 dollars or so, though some places can also take points off your license. Best thing to do is check the local traffic regulations where you live because they vary quite a bit.

Fines vary a ton depending on the jurisdiction and also depend on whether it's your first offense or you've got a record, so it's hard to give you an exact number! What most people don't tell you is that a lot of places let you pay it in installments or with a lower fine if you go to a traffic safety school, so before you pay it all at once find out what options you have in your area.

What matters here is that some countries just charge you a fine on the spot, but others see it as a serious violation that can get your license suspended for a while. In Mexico and Colombia, for example, I've seen that on top of the fine they can impound your bike if you're riding without a reflective vest and a cop catches you in a bad mood. So beyond the exact amount, what really sucks afterward is being stuck without being able to ride.

The reflective vest is one of those pieces of equipment that cops check most frequently during nighttime operations, so if they catch you without it after dark it's probably more expensive than during the day. In several Latin American countries, on top of the fine they can impound your bike for a few days, which ends up being more of a hassle than the money itself because you have to go pick it up from the police station and pay for parking.