It includes nine tools: seven hex bolts, one torx bolt (the star-shaped one), and a Phillips screwdriver (also the star-shaped one). Like Peter says in our guide, if you have a newer mountain bike or road bike it pays to take a quick look at what types of tools you need, as torx bolts are becoming more common. And a quick glance at the bottom of your shoes or derailleur bolts will confirm if a Phillips head is the right choice.
Spare tube: Sometimes, a tube is just too damaged to be patched, or has had a failure such as the valve stem breaking off which isn’t something that can be patched. To save weight and space, I usually keep a lightweight version of the right size tube for my bike. Since one of the first things I do with most bikes that I own is switch them over to heavy-duty thorn resistant tubes, I just take one of the originals and put that in the toolkit.
Basic first aid supplies: A few bandages of varying sizes. 6 Aspirin, or other OTC painkiller of choice. A few alcohol pads in sealed foil packs, useful for cleaning grease off grease and grit off of the bike, and also cleaning cuts on yourself if you take a spill. 1 day supply of any prescription drugs you need to take regularly. Wrap these up in tinfoil and tuck away. It might just save your day.
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:
Modern bottom brackets use a sealed bearing type construction that keeps water and debris locked out, so they seldom go wrong. Maintenance is impossible so they need replacing when they do wear out. Older style cup bottom brackets need to be re-greased every now and again, and occasionally will need to have their bearings replaced. There are a lot more teeth on the chainring cogs than those on the rear cassette, so need changing less regularly. Cranks usually a solid one piece construction so there is not much to go wrong.