For me, my long-range planning for Los Angeles-Mexico-Central America is likely 3-4 years ahead of time. Aside from the difficulties involved in getting away from my spouse, children, business, mortgage, etc., and slowly doing mods/adding accessories on my new KLR650, there are other reasons:
1. need to become a much better mechanic, which I'm not
2. need to become a much better Spanish speaker, which I'm not
3. need to become a much better navigator (GPS, etc.), which I'm not
4. need to become a much better dirt rider, which I'm not
5. need to become physically stronger to handle a KLR 650, which I'm not
Of course, the word "need" is relative, and could just as easily be changed to "want". This is why planning can take years for this kind of trip. I'm not in a hurry, as I intend to take several shorter trips to build up the above skills (Alaska, Baja, Death Valley, etc.), and I'm really enjoying the buildup to the main event.
[This message has been edited by hava98 (edited 04 November 2004).]