I would second the recommendation of northern India. I cycled from Manali to Leh as part of my honeymoon. Was great
Th route itself is not too quiet so if you get into any hassle there is usually someone there to help you out with in a few hours. My mate got nasty sick and we thumbed a lift with a diesel truck over a 5000m pass to a military post to see their doctor
I would really recommend it, it was our first long distance tour. I am in aberdeen as well. If you want more information about it – maps etc welcome around, or chat about it on a bike ride.
The route goes up over the second highest pass in the world
(although there a few places with claims to this) at 5330m ish. and you can go over the highest in a day trip from Leh at the end (Rohtung la pass)
I wrote the trip up on my blog http://www.muddymess.co.uk – i did it July / August 2009 so you will have to click on the relevant months on the right. quite a lot to read to give you a flavour of the trip.
Any more info just give me a shout dnwsmith @ hotmail.com
What ever you do wish you a great journey and adventure.