You will only make good time if you are in the first wave to leave Clapham Common, otherwise think of it in terms of pen 9 at FLM!
Last year it took me two hours just to clear central London. There is always an accident or two to hold things up as well. [sympathies to the accidentees].
I've only ever had a couple of water bottles on the bike and a couple of choccie bars. There are plenty of checkpoints along the way and they are generally very well stocked with all sorts of food - bbq's, sandwiches, cakes, fruit. Many are set up by scout and guide groups so the snacks are well priced. The pubs en route are obviously more expensive.
Being fit enough to peddle up hills is obviously a good thing, but there is likely to be 20 people in front of you on their trusty-rusty with shopping basket who have absolutely no hope of cycling up a ramped kerb, let alone a 1-in-5 hill, so you won't get the option either.
Don't let the ascent of Ditchling Beacon upset you - the ride down the other side at 45mph makes the pain worthwhile!!
It's a party - enjoy it!!
