I'm also planning the same trip, only from Manchester.
I shall also be riding a 640 Adventure.
Provisionally I shall be setting off on the 1st August but maybe sooner by a few days. My route is through Turkey, Iran, Pakistan and then India.
I may avoid Pakistan depending on things nearer the time (my parents aren't too happy about me going there) and have been told that shipping from Chahabar in Southern Iran is possible, but I would still prefer to go to the KKH.
Drop me an email if you want to discuss meeting up along the way or planning.