Thank you, Raphaelo!
Once in San Salvador we got to the BMW Motorrad dealership. Remember the ABS light was on since Guadalajara? Raphaelo, the BMW technician found the problem and fixed it in 30 minutes. I can tell for sure his skill saved our trip: only 2 days after this, while we were riding through a village, a child suddenly started crossing the road in running. I saw him only at the last moment, as he was hidden by a stopped bus. The speed was around 80km/h and I think I saw him when he was less than 5m ahead of me. Without ABS we (and possibly the kid) would have been history. I literally missed him by less than 10cm… Thanks again, Raphaelo!