Why not post your list?....and then we can pick it apart!
Here is my short list:
Credit Card/ATM card/more than one.
Cell Phone with SIM codes so it will work in foreign lands
Email of your parts man/dealer
Brand new sealed type battery ..... just do it!
Dummy wallet with spare expired passport and license
Earplugs....as suggested....a must for less fatique on long rides and for sleeping. Get the good ones....Pura-fit 6800 or Howard Leight. I buy by the box (200 pairs).
Tool kit...one that's been used to pull bike apart. Should include tire changing/repair stuff, spare parts, fuses and electrical, Quik Aluminum or othere Quik Epoxy that will bond steel/Aluminum.
Skills to repair bike.....can't help with this one.
Decent wet riding gear
Good ventilated dirt bike type gear for heat/humidity (this is the part some UK
guys can't work out.....can't really grasp just how HOT, HOT is and what 90%
humidity feels like. Dirt gear packs small and light...bring it.
Proper protection....I used dirt bike knee pads under dirt bike vented pants,
even in HOT weather. Hip pads too, vented gloves.
Good boots you can walk in.
Properly prepared bike.....Let an expert assess the bike to find faults you may
have missed. You don't want to be in Turkey or Iran to find failed systems
you could have dealt with before leaving. Don't wait...do the fixes NOW!
YES...it seems you're money is pissing away...but better to NOT have these problems on the road.
Good supply of anti-biotics, anti-diaherrial, and first aid kit.
Having said all that....be sure to travel as light as you can. Remember, you don't need a liter bottle of shampoo...most stuff is sold everywhere including
bike riding gear, sunscreen, bike parts(common ones) and medicine.