Packing List - Bike Repair
The range of tools to carry correlates with a cyclist's mechanical skills. No need to carry tools to rebuild a bottom bracket if you've never done that, and have no plans to learn. Instead, be prepared for common, and easily fixed, problems.
I like to keep these tools in my handlebar bar, or an outside pocket on my panniers where they can be quickly reached. These are for the most common of road problems; a flat tire. I prefer to use a good frame pump (like the Topeak Road Morph G), rather than CO2 cartridges. A multitool, such as Crank Brothers or the Topeak Alien II, will cover most small repairs. If you've had problems with broken spokes (in 30+ years of cycling I've had two), then an emergency spoke repair kit may be worth the space.
What? You don't carry tubes because you ride tubeless? Okay, sure, I'm still old-school on this one because it's just so darn easy to repair a flat. I also like the ability to quickly swap out tires depending on the nature of the tour. Once I standardized on high-quality touring tires, such as from Continental and Schwalbe, I managed several multiple-week rides free of any flats. My 29+ gravel bike does have tubeless tires, which are great since after more than two years of riding I've yet had to have a flat. Thankfully. Because I'm not looking forward to the convoluted process of sliming my tires.
But to be fair, others say it's an easy process to master. And if you're riding rough terrain with ample opportunity for nasty thorn damage, then tough tires filled with puncture-sealing ooze can be appealing. The folks at BikePacking.com have a FIELD GUIDE TO TUBELESS TIRE REPAIR AND SETUP, in which they state "In our opinion, tubes have long been dead." To illustrate the ease of tubeless repairs they provide more than ten paragraphs of background information, two YouTube videos, and a recommended 11-piece repair kit, which, ironically, includes a spare tube. What a great sense of humor those folks have.
In my opinion? If you're running tubeless - you're banking on NEVER having a flat.
For rides longer than a day or two, a few more tools are handy to have. At the end of the day, if I've had a flat, I'll repair the tube with a simple tire patch kit. I've never had a sliced tire, but if it happens a tire boot (or just a section of an old tube) will keep you on the road. Rather than carrying a whole stack of cone wrenches, I take a 15mm just in case I need to remove my pedals. Cone wrenches aren't heavily built - just make sure to loosen and then re-tighten pedals at home so that they're not frozen.
Broke spokes. Ugh. Most breaks are easy to repair - as long as you have the correct size of spoke on hand. But spokes on the drive side (back tire where the gears are) require the cassette to be removed, which means carrying a chain whip. A reasonable alternative is the Stein mini-cassette lockring tool. Around $40 and hardly weighs anything. Just make sure to review some YouTube videos before getting on the road - the included instructions aren't worth much.
For longer rides, or shorter ones in bad weather, it's good to spend some time keeping the chain and gears cleaned and lubed. An old toothbrush works well for cleaning out road debris. With enough miles, carrying spare spokes, cables, bolts, and tires may be appropriate.
From a somewhat unexpected source, Popular Mechanics has The 8 Best Bike Tool Kits for Quick Repairs on the Go, including a handy tool for plugging tubeless tires.
There's a...multitude...of multitools to choose from. GearLab rates The 6 Best Bike Multi-Tools of 2023
From the good folks at REI comes a general discussion of Bike Tool Essentials, covering both home and on-the-road repairs.
Wondering what other cyclists carry? Backpacking.com does and answers it with One Question, Five Voices: What's in Your Tool Kit?