Any bike that gets ridden seriously as transportation or on long rides needs at least a basic tool/emergency kit, and the knowledge to use it, unless the rider is always in a position to call a friend with a car or a cab when their bike needs a quick fix on the road.  If you never travel more than a few miles, this can be overkill, and calling a friend or a cab may be just the ticket,  but if you want to be more self reliant, this is something you should seriously consider.  This list may sound like an awful lot of stuff to carry, but really, it only weighs a few lbs and fits in a small, under-seat bag that comes off quickly so I don’t have to leave it with the bike if theft is a concern.  If you always carry a regular rack top bag, you can also just put all this in a small nylon bag and throw it in there, but I prefer an under-seat bag.

Inside Student Union across from College Optical, the UCF Bike Repair Service is provided for students with bike problems. Students may come, free of charge, and have their bikes repaired with quality service by our Bike Repair Team. Service include: Inflate tires, change tubes, brake adjustments, tighten crankset, loose handlebars, adjust gears, and brake cable installation. Bikes can also be reserved here as part of the Bike Share program.
A plastic garbage bag, or $2 disposable poncho:  Just in case of an unexpected downpour or getting caught out after dark.   More than once, I’ve gone for a ride on a beautiful day with a perfect forecast, not taken a jacket and had the weather go south on me.  Being able to cover up can mean the difference between just mild discomfort or a freezing cold, shivering ride home!
I own the Lezyne CNC Chain Rod, which I’m a big fan of (yes, I know I’m partial to Lezyne here–they’re a local-to-me, San Luis Obispo company and they sponsored my collegiate team, so I got tons of gear) and it costs right around $30. But the truth is that even the cheapest of chain whips will likely do the job. In fact, I’ve found a dude who knows his stuff and shows you how to make this tool all by yourself. I would even go so far as to say that you probably have enough materials laying about your garage (if not, try your parents’ garage ? ) to put this together without spending anything. Check out the video below:
As you mentioned, it is surprising how often you can get multiple flat tires on while riding, particularly on longer sprints. The tip about bringing a patch kit in your bike repair kit can be incredibly helpful if you’ve already had one flat tire. I agree that all you listed seems like an awful lot to carry, but it’s always better to be safe than sorry, isn’t it?
Many bikes, including older models and track bikes, have bolts attaching the wheels to the frame instead of quick-release levers. If your wheels are bolted on, in most cases you’ll need a 15 mm wrench to remove it. We didn’t test wrenches, because there aren’t that many tiny 15 mm wrenches, but the GearWrench 15mm 12-Point Stubby Combination Wrench is perfect for stuffing into a flat kit and Amazon reviewers seem to think the same. Our experts also recommended the Surly Jethro Tule, but it’s expensive and harder to find.

There are two major types of headset- older, threaded headsets that have a quill that drops into the stem of the fork creating an interference connection, and newer threadless headsets that the stem is bolted and clamped on to. Flat handle bars are preferred by off road cyclists who can ride in a more upright postion whilst still having the controls at their fingertips, whereas drop handlebars offer more cycling positions and are favoured by road cyclists who typically spend more time in the saddle. The controls attached to the different styles of bar are operated and maintained in different ways.
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