We spoke to a broad spectrum of cyclists—from a pro racer to a bike messenger turned mechanic to a touring cyclist who has logged thousands of miles throughout Europe—to find out what items they find indispensable. We sorted through 40 tire levers, almost 30 different kinds of patches, 120 different hand pumps, and 57 seat bags before we narrowed our choices for testing. And then we changed and patched tires more than 50 times, using four different bikes, five different wheels, six different tires, and almost 10 different sizes of tubes. After 96 hours of combined testing, we agree these essentials are some of the best you can buy.
These guys are awesome.  After work, I got to my bike to discover my back tire was completely flat.  It had a slow leak, so I was able to pump it up enough to make it to their shop.  I got there 10 minutes before closing and they were able to fit me in.  They replaced my tube and picked all of the glass shards out of my tire.  Awesome customer service and they saved me from having to do this myself in the dark and the cold.

I just got a tune up on my bike and it rides so much better now! It takes half as much effort to petal, it is like a new bike. The guys who work there are so nice and always make you feel like your time is important. They don't overcharge or sell you things you don't need. I thought for sure I needed a new chain, but as it turns out, it's fine! He gave me some extra foam for my bike helmet, free of charge! I'll definitely come back here for all my bike needs!
If you’re going to use the chain whip you just made, you’ll also need a way to get that cassette off. A lockring remover is a must-have; unless you use one of the shady removal methods I’ve seen on the internet—which I wouldn’t necessarily recommend unless you don’t care much about the condition of the wheel after you use them. I recommend Park Tool’s iterations here that cost about $6, but you’ll need to buy the specific one for your brand/type of cassette. (By the way, I’m assuming you already have an adjustable wrench laying around somewhere to use with this tool. If you don’t, well, you’ll need one of those too.)

All multi-tools are not created equal, but most with a plethora of features will get plenty of the jobs done. I personally like, and use often, the Lezyne RAP-21 LED tool, which will run you around $30. I like it because not only is it a high quality construction, but it has just about everything you’ll need, plus a sweet mini light. This will give you a chain breaker, spoke wrench, disc brake wedge, and all the most often used Allen keys and drivers. We’re talking a decent number of tools for 1/4 of what they would cost buying them separately.

Friction gear systems are a lot simpler to adjust, because the movement of the derailer cable can be modulated as you ride, every time you change the gear- they require less cycle maintenance. Modern index shifting systems are a little more complicated because each ‘click’ must release the exact right amount of cable to allow the derailer to move the correct distance to move the chain from one gear to another. Setting up and adjusting a derailer is not difficult and requires only basic tools, but there is a methodical procedure to follow.