Here's the bike setup I am going with.
Trek Madone 5.2 carbon bike
Reynolds SixtySix clincher wheels
Tyres: Continental GP4000s (The best tyres ever made in my opinion. The front tyre on my tourer has done over 6000 miles and I've only had 8 flats. Incredible.)
Tri-bars for comfort and speed
A saddle bag and top tube bag for spares, wallet and phone etc.
Cycle GPS for navigation. Saves loads of time not having to mess around with maps.
Good lights for night cycling with at least 8 hours battery life if possible.
Two water bottles. It's likely you'll have to drink about 6 litres of water so will have to fill up a few times. Don't carry too much water as it's the heaviest thing to carry.
Clothing - I'm carrying only cycle kit so will have to take the train back a bit smelly but want to save weight.