Here's a quick guide on what to pack when you ride. Everything pictured is exactly what I take with me on rides that are more than an hour. Although food/fuel IS essential, it's really a rider's personal choice on what they'd like to take with them.
1.) Hydration System - plain English? - WATER! The more the better, especially for the long "epic" rides. These systems are commonly known as "Camel Backs" due to the industry's leader - Camel Back. However, there are many alternatives, at a much lower price and will ultimately give you the same outcome - water in mouth. This particular one(pic above) carries a 70 oz bladder with a few tight pockets to shove the rest of my tools in. I also have another one, that's more like a small backpack with a 100 oz bladder and space for everything you can need for a day long trip. Gotta be careful though and NOT over-pack or you may regret carrying all that extra weight unnecessarily. A water bottle is great for carrying your fuel-based or other "High Activity" repleneshing or power drink, but usually never enough by itself.
2) Flat tire repair kit - a collection of tools that will get you out of 99% of your flat tire scenarios. You've got to have your Dual-Action mini pump which makes pumping air as efficient as possible by pushing air on both the up & down stroke. Preferrably one that fits both Presta & Schrader valves so an attachment isn't needed. This one is ok, but there's much better on the market today for around $30-$50 that should last you for years. Also pictured are 2 Tire Levers($2-$5), 2(you can never have enough) - patch kits($2-$5), 2 Schraeder valve stem nuts and a Cap(these last 2 items you would get from a spare inner tube). Learn how to fix flats since this will be your #1 issue when riding. I've gone months without a flat, riding on some of the roughest terrain around and then I've hit a streak where I get a flat almost every ride(most ever in a ride for me? 5!, no lie, it sux! . There's really so much you can do to prevent flats, tire liners/green slime tubes/thicker lined tubes, and I've found that keeping the tires properly inflated will eliminate most flats. With some practice, it will take about 12-15 minutes including the exhausting pump action. Or you can get a CO2 cartridge and fill it up in 30 seconds. I don't have one because I've simply gone through too many of them and honestly, the mini-pump is always ready to go....for free! :)
In the event your tire gets torn open, instead of the usual poke, simple patches may not work. Items like folded dollar bills or scrap pieces of tire walls can help seal the tear long enough to get you back home. It's happened to me and believe me it works! Check out the pics below...
Other Essential Tools for the ride
Everyone needs to get a Multi-Tool which is the Swiss-Army knife for the mountain biking world. The one above is a TOPEAK - McGuyver and has everything, and some, that I have ever needed. That wear you see on the chain breaker tool(lower left) is legit; I've probably had to use it 5 times and it has prevented having to call in a search party for me. :)
Make sure your Multi-Tool has the essentials: Allen Wrench in the usual 4 sizes; Chain Breaker Tool; Small Knife; Pliers; Phillips Screwdriver. Anything else is great, but I haven't found it to be as necessary.
That's pretty much it as far as what to carry on every ride.
*Food, like I mentioned, is really up to you. There are certain foods that sit better with some riders than with others, so you need to try them out. I'm going to write a post about what I eat and take with me later on.
I will end with suggesting you practice using these tools so they're not foreign objects to you if and when you need them. Check out my YouTube videos for a few tutorials on "How to..." and get started.
To epic rides & weather!!!
Juan