Sir (I'm sorry, I don't know your name):
You have raised a number of issues that are not necessarily related or linked to each other.
Concerning driver licencing: Provided you hold a valid driver licence for the class of vehicle you are operating, you should be fine. By 'valid', I mean that the document has not expired.
In theory, you should have an International Driving Permit (IDP) in order to use the driver licence in countries other than the country that issued it, but that is very much "in theory". The primary purpose of an IDP is to provide a translation into other languages of your driver licence, and since you will be travelling entirely within Spanish-speaking countries, and your driver licence is likely inscribed in the Spanish language, translation should not be needed.
Be aware that IDPs can only be issued by the appropriate authority (usually the national motoring club) of the same country that issued the driver licence. That could make it difficult for you to get an IDP, unless you get one before you leave Colombia.
Concerning the licence plate on the motorcycle: There is an international convention that permits international operation of vehicles and mutual recognition of foreign vehicle registration. Hence, if the moto is properly registered and plated in Colombia, and the plate is valid (not expired), that is sufficient for registration purposes in other countries. You should display a oval white sticker on the back of your moto showing the country code for the country of registration. See this Wikipedia article for more detail:
International vehicle registration codes. You can usually obtain one of these stickers from the same office you get the IDP from, if in your country they are not commonly sold at gas stations, vehicle parts stores, etc.
Concerning permission to temporarily import the bike to other countries along your route: Generally speaking, if you are a
bona fide tourist or a
bona fide transit traveller (enroute through one country for the purpose of going to another), customs will permit you to enter and ride through a country without formalities. You can expect that they will check your ownership and registration documents, and you can also expect that they will check your insurance documents to confirm you are properly insured for operation in the country you are entering.
Some countries require that you have a carnet in order to enter with a foreign registered vehicle. A carnet is basically a bond, a bank guarantee that provides assurance that you will not leave the motorcycle in the country you are touring or transiting without paying the import taxes, duties, etc.
You will need to do your own research to determine whether a carnet will be needed for your trip. There is a discussion here in the HUBB about carnets, here is a direct link to it:
Carnet - everything you need to know starts here!
I don't know anything about carnets. I have been told that they are not required by countries in the Americas, however, you will have to confirm this yourself.
Visas: One question you did not ask, but need to research on your own, is whether or not you will need a visa in order to enter all the countries along your planned route. Whether or not you will need a visa (or visas) depends on what passport you carry, what countries you plan to enter, and how long you plan to stay in each country. You will have to do your own research on this. Visit the websites of the different countries you plan to visit to find out what their policies are for visitors of your nationality.
Michael