Below is a cut and paste job from an e-mail I received from Gonzalo - it's got a lot of good info for folks heading South from the States:
1) No carnet or libreta is needed. We have covered about 40.000 miles
in Latin America on various trips and never used one.
2) Darien gap: most common is to airlift to Colombia or Ecuador. Use GIRAG Cargo from Tocumen Cargo airport in Panama city. They have done it a million times. USD 250 per bike to Bogota, Colombia or USD 500 to
Quito, Ecuador. Dimensions and weight of bike dont matter. Fixed price. Contact
Rene Peredes (speaks good english) , airport manager for Girag, tel. 238-4326 / 4397 / 4289. Rene might have retired (was about to) but Girag is always there. Paperwork is a piece of cake.
3)Borders I recommend: (a) Mexico-MEXCICALI (do NOT use Tijuana as vehicle
entry papers not available), (b) Guatemala -LA MESILLA (c) Honduras -EL FLORIDO (d) Nicaragua - LAS MANOS (e) Costa Rica -only
one possibility on Panamericana (f) Panama -same as CR. Stay away from all borders with heavy truck traffic unless you want to spend time and money on bribes. In addition, look for my post entitled "Official Panamerican
Border fees" on the Horiz. Unlimited Bulletin Board. Those are the CORRECT
prices/entry fees for Central Amer. borders. I posted this info in May
2001. South American borders are much more straight forward and free of charge.
4) If your bike enters Quito by air contact fellow ecuadorian biker Ricardo
Rocco (speaks excellent english) at tel. (5939) 722 408, e-mail
aroundforpeace@hotmail.com You will need his help to get your bike out
of Customs. The process is a pain in the ass, they will initially ask for a
Carnet, but me (and many others) have gotten our bikes out without one. Be
patient and talk to Rocco. Or ship your bike to Bogota (much easier) and go
for it.
[This message has been edited by waward (edited 25 November 2001).]