Other Tips

Make sure that your bicycle is of the right height and that once mounted, you are able to place both feet on the ground. This is necessary to ensure that you are able to break any falls, in case of rugged terrain or bad road conditions. Also ensure that the bicycle seat is comfortable and suited to your height and weight.
On long rides such as the Manali-Khardungla Cycling Championship, always carry two bottles of water - one for drinking and the other for washing dirt off scrapes and bruises or for cleaning equipment. Also carry enough energy bars or high carbohydrate snacks and energy drinks to keep you going.
A basic first aid kit containing bandages, antiseptic lotion/cream, cotton, pain relief sprays, standard over the counter anti-allergens and anti-pyretic drugs and your prescription drugs if any, is a must in your backpack.
Make sure that your bicycle is in good condition and that the brakes, gears and wheels are all running smoothly. Watch out for strange sounds or unnecessary drag. It just may mean that an overhaul is required.
If this is your first long distance ride - always, always, always - train for the distance you are challenging to do. A good weight training program coupled with regular bicycling bouts before D-day often makes the difference between success and failure, no matter how short or long the journey is.