Lots of opinions here, some of them backed buy direct experience. #5 and #6 give good advice above. I'll add:

El Salvador is great fun, and the mountains are gorgeous in addition to interesting in terms of recent history (i.e., US-funded wars wreaking havoc from which the country has yet to fully emerge). Keep your ear to the ground, but don't be intimidated by vague reports.

Most people don't worry about tracker/locator beacons and such. You may choose to carry one, but you certainly don't "need one."

Internet is available *almost* everywhere, although sometimes it's slow or uncomfortable. Wifi is not always available to travelers--this will depend on what sort of places you go or stay. Hell, even beds, shelter, electricity, food, cell service, and potable water aren't available everywhere. On the other hand, in some countries the wifi is far better and more widespread than in the USA.

Cheapest functional travelers insurance, including evacuation if needed, is available from DAN, a diver's membership organization. You don't need to be a diver to join. Look into it.

There are good reasons to carry emergency cash, stocking up in countries which use US dollars or Euros (Ecuador, El Salvador, Suriname, Panama). Not only are there countries with parallel (black) currency markets (Argentina, Venezuela) but there will be times when you can't access funds for a day, maybe two, for mysterious reasons. And you will definitely need to carry more than just one or more credit cards.

Most people planning to ride down and then back find that they run out of steam and end up shipping, selling or (rarely) storing their bikes. Just keep that in mind when making plans.

Hope that's helpful.

Mark