There are actually two questions here. What bike kit do I need can mean, what BIKE do I need? And also, what bike KIT do I need?
We saw some really expensive bikes on the ride. I mean really expensive. My brother, who is an amature cyclist, said to me “see that bike over there? the wheels alone are worth 1500 GBP.”
We also saw people on kids bikes, and I mean 12″ bikes doing the ride as well. We saw someone on what looked like a large modern penny farthing, plus a lot of tandems.
There were all sorts of brands as well, everything that you could possible imagine. Some I recognised, others that were obviously very specialist and expensive…
All I would suggest is that the bike has to be in good condition. Ideally, if its an old bike get a service done on it (assuming its not been looked after for a while) as they can align the gears, sort out loose breaks, align the wheels and ensure the chain is in good working order. This can be expensive though after they start to charge for the bits that they see need replacing.
You can service your own bike, again, checking breaks, gear alignment and making sure the chain is in good order and oiled.
If you want to get a new bike, then really think about what you are going to use it for. I have always had mountain bikes, up until I got a hybrid bike. I bought one which was designed for road, but had suspension and could go off road as well…
If you do get a new bike with suspension, try to get one with a lock off. Rear and front suspension is fine when you are going down a muddy hill in a forest, but when you are going up Ditchling Hill, a lot of your energy is lost into that suspension (you weight pushing down pushes the suspension, not just the pedals, so not all energy is transfered to the bike wheels!). A lock off is HIGHLY recommended.
Tyres are important, as is tyre pressure. I would recommend, if you are using a mountain bike, buying tyres that are NOT knobberly. Getting some road tyres can really help reduce rolling resistance and make the ride easier. Plus again, you get energy loss with large bouncy tyres.
When it comes to a bike, just make sure that you do what you can to mitigate ending up getting stuck half way round with a (heavy) bike that you have to carry to the finish because the chain has broken, or the crank has gone…
Kit is important but again, you can spend as little or as much as you want. A bike pump, a spare inner tube and a bike widget to take the tyre off if (or should I say when) you get a puncture. I suggest a new inner tube as that is much quicker, easier and more reliable than trying to fix a puncture whilst out on the ride.
All of those bits combined would cost less than 20 quid.