Change and a $20 bill:   In case your cell phone’s battery dies, it’s nice to still be able to use a payphone if you need to.   Also, the $20 is a great thing to have in case you lose your wallet or have some other mishap.   I’d rather be able to sit in a coffee shop or fast food restaurant when it starts raining while I’m waiting for my friend or cab ride, and a hot cup of tea or coffee or the beverage of your choice and a snack makes it all the more pleasant.  Just try to remember, this is for emergencies, and if you use it, replace it ASAP!
A multitool is a highly versatile piece of repair equipment that can address most of your maintenance needs. Ideally, you should use it before a ride to tighten and adjust everything properly, but sometimes it’s necessary on a ride as well. If you encounter a loose screw, realize your saddle height is not right, or that your brakes need tightening, you will be happy to have it.
The Pedro’s lever slipped only once throughout testing, though that may have been my fault because I was spaced out after changing 16 different tires. So they’re not foolproof, but they are far and away more reliable than the next closest competitor, from Park Tool, because the small, rounded tip on that one is hard to keep seated under the tire. Not impossible, but I wouldn’t choose it over Pedro’s.
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.)
This is the shop I hoped to find when I began commuting two years ago. I'm a daily commuter and I love knowing that these guys will help me almost anytime that I need it. Andy, Jake and Brad listen and make sure to help me as best they can and are always speedy about it. Additionally, they encourage me to do my own work on my bikes when I have the time/when they know I'm capable and I really appreciate that encouragement.
Broadly speaking there are two major wheel sizes – 700c for road bikes and 26 inch off-road wheels. However there are a whole variety of older, less common wheel sizes and of course fold up bikes have much smaller wheels altogether. Repairing a puncture is not an emergency! It’s a basic procedure that every cyclist should be able to to perform, but doing it correctly involves more steps than many people realise. Wheel building is often seen as the most artful skill in bicycle maintenance, and separates the professionals from the amateurs but that doesn’t mean you should consider it out of reach. Truing a slightly misaligned wheel is a cycle maintenance job that almost any cyclist can perform.
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