Thanks for all the answers
I'm now in California

I heard some other boats like The Independence are no taking motorcycles anymore since our experience.

No idea if the Stalhratte will be able to do it. Hope so !

Just keep in mind that leaving this way, with these 'illegal' boats, you're ok but your motorcycle is leaving the country illegally. To correctly leave the bike from the country, you have to cancel the temporary vehicle permit you received at the entrance border. And the customs of Cartagena won't cancel it if you're leaving this way. They only accept official cargo ships and flights.

This is not really a problem if you don't plan to come back in Colombia with the same motorcycle. But you plan to, just be careful to that. We tried hard to cancel this temporary permit before taking the boat (even if it finally never left) and there's no way to do it if you use the sailboats. Even if a colombian 'agent' says to you "30 USD and I care about it", all he will do it to throw the paper away and you'll never know before coming back to Colombia.

They say that the border systems aren't connected and it's not a problem not to cancel this permit, that they'll never know when you'll come back, but I don't believe a word. Feel free to take the risk ;)

Cheers !

Record keeping in Colombia
 

I have heard that the record keeping in Colombia is a mess and those that leave without following official procedures have little to worry. I guess we have to wait and hear the story when someone tries to re-enter Colombia...