It might help if you said where you are planning to enter and exit.
Are you shipping in from Indonesia? Shipping into India is a major headache in itself.
Pakistan requires a carnet. Iran doesn't, but it is a lot easier to have one. Nepal uses the carnet system too - I don't know if it is compulsory though.
Having gone in and out of India a number of times, my impression is that entry without the right paperwork is nearly impossible. I have come across only one person who got into India without a carnet, a Brazilian on an Aprillia several years ago. He cried and cried and cried, until the border guards didn't know what to do with him, so they let him through. Not a tactic that will necessarily work for everyone.
Around the world 2000-2004, on a 1993 Honda Transalp