Best bike multi-tools: Well-equipped bicycle tools, tested and reviewed

In short, yes. 

It's a really good idea to carry at least a basic tool that allows you to adjust your bike and tighten bolts down. Components can work loose and move due to vibrations from the road or even fail from time to time. If something prevents you from continuing a ride that could have been easily solved with a multi-tool or Allen key then it's probably worth carrying one. It could also help a fellow rider who is stranded or in trouble, especially in isolated areas. 

A bike multi-tool is a compact and versatile tool designed specifically for carrying out emergency roadside repairs or quick on-the-fly adjustments during your ride. They’re always portable, small enough to carry in a pocket or saddle bag and combine various tools into a single unit, like a Swiss army knife or Leatherman tool. 

Typically, a multi-tool will come with a range of Hex keys in different sizes, which are used for tightening and loosening bolts and screws. These make it possible to adjust your saddle height, or tighten a loose and rattling bottle cage or mudguard, for example. They also tend to feature Philips and flathead screwdrivers, as a minimum. 

Other tools included vary from model to model, making some better suited to certain uses than others. Whether or not you want a multi-tool that comes with tubeless tyre repair parts, a chain breaker tool, or Torx wrenches, is totally up to you and your individual needs.

A good place to start is to make a list of the sizes and types of fasteners and bolt sizes on your bike/s. There are almost certainly going to be 2/4/5mm hex keys and perhaps 6/8mm for your disc thru-axles if you have them and pedals. These are the essentials to make basic adjustments and tweaks. 

If you own more than one bike, see which sizes are most common and look for the tool that matches the majority. 

Then depending on how much you want to spend and carry you could add more features like a chain tool - this is always useful. And things like spoke keys, valve core tools etc. 

No one wants to be loaded down with a full tool kit while riding, so cyclists often carry a multi-tool that fulfils most of the duties that are likely to be required. More often than not these are small adjustments to seat posts and the like, but also you want cover for worst-case scenarios.

While many cyclists will also carry a puncture repair kit of sorts, some of the best bike multi-tools come with elements to help with this, such as tyre levers or even tubeless tyre repair kits. 

Regular home maintenance can help keep your bike running smoothly, and hopefully prevent some of the most common issues from happening in the first place. If there is a specific component you have been having trouble with, you could always bring out the particular tool you know will help you to adjust it. If for example you know you'll be adjusting your new cleats on a ride, take a full-size 4mm Allen key with you for the shakedown ride.

The majority of your bike can be disassembled with a 4mm and 5mm Allen key so, at the very least, the best bike multi-tools should have Allen keys with these two sizes. It’s also worth having a 6mm. While some tools may have an 8mm or 10mm bit, quite often they aren't much use because the tool doesn’t offer enough leverage to break a bolt that size loose. An 8mm is a useful size though when travelling for installing pedals. 

Some bikes also use Torx bolts, usually in a T25 and sometimes a T30, and a small Phillips head screwdriver also comes in handy for derailleurs. 

The other tool we prioritise on a bike multi-tool is a chain splitter. Even if you have a quick link in your spare tyre kit, you’ll need a chain tool to pop the old link off. Quite often the chain tool will also have spoke wrenches built into the lever.

And along with the rise of tubeless tyres comes the need for new tools. A valve core remover isn't something many will need to use at the roadside, but if you don't have one at home (or if you lost it again), then it's good to know there's one built into your multi-tool. 

Multi-tools also now include tubeless repair tools and if you ride with a tubeless setup on most of your bikes it's a good idea to get a tool with tubeless plugs, an insert tool or a CO2 inflator.

Yes, of course, plenty of cyclists have been carrying the same multi-tool for many years in their saddle bag or pocket. You can use whatever works for you. I still have an old multi-tool I was given years ago that's small and fits the bolts on my bikes, it even has crash damage from sliding on the road. 

If you prefer a Leatherman-style tool or anything for that matter, use what works for you. 

Some more extensive bike multi-tools have extras such as tyre levers, torque wrenches and bottle-openers. While a torque wrench can be useful out on the road, primarily if you're dealing with carbon components, the rest is a matter of personal opinion – do you think it's worth carrying the extra grams? 

Ultimately, tyre levers only weigh a few grams, and even an expensive set doesn't cost all that much or take up much space in your pocket. When it comes to multi-tools with fun additions such as knives, pliers and bottle openers, they might be used once in a blue moon but are they really going to be useful for your Sunday club ride? Once again, it all comes back to considering your own specific needs.