Even the most reliable bicycle is subject to wear and tear during a tour and any part has the potential to fail and stop you on the road. Like most cycling tourists, I am not an experienced mechanic and in a dozens tours with different type of bikes I have so far completed, I mostly had to deal with fixing punctures and some basic gearing or brakes adjustments.
Although some people are doing exactly that, I would not recommend a Brompton bike for unsupported extreme expeditions or round the world trips where you will be spending weeks without the chance to access basic facilites or other forms of transportation should you need to.
Even if you were a skilled Brompton mechanic, the limitation on the amount of gear you can carry with you, means that you could easily find yourself without the right tools or spare parts to be able to fix it and continue.
Bromptons are mostly built with proprietary parts that are not easily accessed in remote areas and your run of the mill local bicycle shop might be at a loss in trying to get your bicycle back on the road.
Where this folding bike excels instead is
in multi-modal touring and short to medium tours where you will have access to alternative transportation in case of emergency and if possible access to shops where spare parts can be found. The latter is not a must provided that you are happy to take the risk of an unlikely failure that could stop you from cycling; even in this situation having a folding bike that you can easily pack away and a rucksack you can quickly put on your shoulders makes for a good chance that your touring holiday will not end in total frustration.
Before you set off on a tour, always make sure that your bike is in good conditions. Like I said above Brompton's are sturdy bikes but if you have the bad luck of running into a major failure, they are not as easy to fix as a regular mountain bike or racing bike. Before starting my tour I usually service my bike at a Brompton dealer, as they are the expert and know what are the parts that mostly need looking at for wear and tear. I am not sure it makes any difference, but I do mention to them that I am going on a tour and ask them to pay special attention to critical parts such as wheels, chain, etc.
In the last few years global popularity of Brompton bikes has rapidly grown meaning that dealers are now rapidly expanding and can be found more and more in towns and cities all over the world. Access to them while you are touring in your destination might not be as difficult as it used to. I usually take a flight to the starting point of my tour and as much as possible I pick a destination that will have a Brompton dealer available should I need to. I haven't had the unfortunate event of a bike damaged by airline transport but this is obviously a possibility and if you are not far from a Brompton dealer, once arrived you will probably be able to repair the bicycle without losing too much time or having to change plans. Further along these lines, if this is an option, do some research and know where easily accessible Brompton dealers can be found along your touring route should you need to get some spare parts, fix things or simply having a check on your bike during your tour.
The most likely repair you will have to carry out during your tour is a puncture tyre. The procedure for removing the tyre from the wheel and replacing or fixing an inner tube is the same that you would follow on any other bicycle. What is trickier on a Brompton is removing the rear wheel in order to replace the inner tube. I found the
Brompton Technical Guide youtube videos a valuable resource to learn to do so. Do not rely simply on watching the videos or read manuals though, as always practice only makes perfect! To be prepared start by removing the rear wheel at home where you have access to all your resources should anything go wrong. Once you are a little bit confident the next step is to take your Brompton for a day ride and do the same repair by the side of the road without having access to videos or manuals. That way you will be well prepared and much more confident once you start your tour and a puncture will be just a minor frustration and a good excuse to have a break and enjoy the scenery!
Replacing the tyres. Small wheels mean that your tyres will wear out much quicker than you think. Even the best of tyres if you are cycling past 1000 kilometres will start to show some wear and tear, especially in the rear wheel. After my first extended tour on a Brompton where I had to swap rear and front tyres half way through my journey I decided it is a good idea to bring two new tyres with me in case I need. Being small means that they are lighter and that they can be easily slid on the outside of my backpack, a perfect and unobtrusive way to carry them for any emergency. In my experience 16" tyres in most countries are associated with children bikes and even though you could access a bike shop easily you might not find a spare Schwalbe Marathon in that size and what is on offer might be completely unsuitable for your purpose.
Adjusting a Sturmy Archer gear cable. In order to have your gears perform well it is sometime necessary to adjust the little chain alignment. If you removed the back wheel you had to learn to losen that anyhow so it should be something you are familiar with already.
Lubricating the bike. This is straight forward but again a Brompton bike is built in a different way and it is important to know which parts need lubricating and which part don't. Any extended tour involves you cycling for days and chances that you will also encounter bad conditions such as rain or dust on the road means that your bicycle will need some more attention in this department too.
Learn to carry out basic safety checks. These are often found in the manual that came with your bike. Make sure you do this before you start your tour in order to assess the condition of the bike after it was transported to your destination. Get into the habit of having a quick check each day following the manual recommendations.
If you are inclined to, it will certainly help learning a few more advanced repairs.
Fixing a broken chain. I never had a chain failure on my trips but it does happen. If you have the right tools with you it could be the difference between being able to fix it there and then and continue cycling as opposed to having to itch a ride to the next town. The good thing about a broken chain is that you won't need a Brompton specialist to fix this, any local bike shop will be able to quickly offer help and repair it.
Fixing a broken spoke. Again not something I had to deal with on a Brompton so far. This is a tricky repair mostly due to the difficulty of truing a wheel once a spoke is replaced, an art in itself. If you can learn this it is something that again might save you a long walk to the next town. I haven't mastered it myself and for this reason, one thing I do make sure is that I carry spare spokes with me. This is important because like a chain every bike shop will be able to help you but might not have the right spoke sizes for your small wheels! Again children bike's spares are not always of the quality you need for your more 'grown up' bike!
Replacing braking pads. If you are going on a 2000 kilometres or longer tour you might have to swap your braking pads too. This is a straight forward procedure and even though I never did change them during a tour they are small and compact enough to carry and I always make sure I have a spare set just in case.
2 Spare 16" inner tube
2 Schwalbe Marathon Kevlar ( expensive but lighter and easier to replace )
Patches and glue for fixing tubes
Selection of Spokes ( rear and front wheel use different sizes )
1 set of Brake Pads
Brompton Front Carrier Block & Clip
1 Sturmey Archer Derailleur unit
Chain repair kit
Screws and Bolts
Brompton Pump
Wrenches: 8mm, 10mm, 15mm
Allen keys: 2mm; 2,5mm; 3mm; 4mm; 5mm; 6mm
Lubricating Oil
Tyre Levers
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All the right keys and wrenches sizes as well as tyre levers are included in the Brompton Toolkit. A little expensive but it fits inside the frame and is very compact and ideal for the job.
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Plastic Gloves ( why get your hands dirty! )
Chain Pusher ( if you know how to repair a chain )
Spoke Wrenches (if you can replace a broken spoke )