I'm an old guy, 65, and I did the leg from the Turkish/Iranian border to Calcutta (ca. 6,500 km) in 16 days. The Pakistan section is very slow, but being improved. Also they will not allow you to use the motorway in Pak., and you have to argue to get on in Iran. You can make it through Iran in 5 days. India is another problem. Do you have a death-wish? If yes, you're in good shape to brave Indian traffic. I was on my way to Bangladesh and Australia, so I was glad I didn't have to go back, as you are planning to do. If you want more details, see my book, "From Nordkapp to Cape York..." listed in the "books" section of horizonsunlimited. Look under "B" for Bausenhart. I say you can do it, in about 5 weeks, but it will be hard on you. "Wer nicht wagt, der nicht gewinnt."