The Amazing Race 23, Episode 6 (FAQ: International Bicycle Travel)

Vienna (Austria) - Abu Dhabi (UAE)

FAQ: International Bicycle Travel

In this week’s episode, for the first time in 23 seasons (several of which have included visits to places where mosques are major tourist attractions), The Amazing Race visited a mosque. There’s a common misperception that non-Muslims aren’t allowed in mosques, but with the exception of the holy (to Muslims) cities of Mecca and Medina, that’s generally not true. I have yet to visit a mosque where respectful non-Muslim visitors weren’t welcome. (Unlike at many Mormon and some Hindu, Parsi, and other places of worship.)

Afghan-American cousins Jamal and Leo finished first in this episode, and emphasized how much “at home” they felt in Abu Dhabi. That might seem strange. They both say they speak only “a little” Arabic (at the mosque, they say their prayers in Farsi), and neither of them is of Arabian ethnicity or ancestry. But it makes more sense when you realize that Abu Dhabi, like most of the other apartheid monarchies of the Arabian Peninsula, isn’t predominantly an Arabian country by any demographic measure. Only about 20% of the population are citizens, and most of the “foreign” residents are non-Arabs, predominantly from South Asia. There’s a particular sort of cosmopolitanism to a place like Abu Dhabi, but only in part is it “Arab”.

In the real world, travellers are much more likely to use bicycles (or to consider doing so) than to ride in racing cars around an actual Formula One course, as the racers did this week in Abu Dhabi. In Montréal, for what it’s worth, you can ride your bicycle around such a track, as I did last summer. The Formula One racecourse in Montréal is open to bicyclists for most of the year as a public velodrome, whenever it isn’t in use for motorized racing.

In recent columns, I’ve talked generally about travel by bicycle and how to buy a touring bicycle. In response to comments, I’ve added some notes on a few specific models of new touring bikes to consider.

This week, I’ll look at some of the bicycling issues — including those related to transporting your own bicycle or procuring a bicycle locally to use while you are abroad, and choosing bicycles and components suitable for use while abroad — that are specific to international travel.

First, should you bring your own bike, rent one at your destination, or buy one at your destination? Each of these options has its own pros and cons:

Renting a bike at your destination

If you are only using a bike for local sightseeing, it usually makes the most sense to rent one locally. Almost anywhere you would want a bike for local use, you can find some sort of bike for rent. For short distances, it isn’t necessary (and may not even be desirable, in light of the risk of theft) to have a high-quality bike or one that fits you perfectly. If you rent a bike, it will probably be of a locally-common type, which is advantageous if it breaks down. I haven’t yet done a long-distance overseas bike tour, but I’ve rented bikes in many countries for local sightseeing.

Fit and reliability become more important, and renting a bicycle locally is less likely to be the best choice, if you want to travel longer distances by bicycle. It can be difficult or impossible to find a quality bicycle for rent, or one that fits you well. Unless you have a referral to a bike rental service from a knowledgeable and trusted friend, you may not be able to tell in advance what condition the bikes available for rent will be in, much less whether it will be possible to get them to fit you adequately. Because bicycle rental is mostly a local business, it’s much less common to be able to arrange to rent a bike in one place, and return it to another, than to do the same with a rental car.

For long-distance bicycle travel, except as part of a supported tour for which the tour operator provides the bicycles along with their other services, you’re more likely to need to find a way either to get your own bicycle to the starting point of your trip (and back again, unless you plan to sell or abandon it at the end of your ride), or buy a bike locally to use for your tour.

Buying a bike at your destination

If you have time, sufficient confidence in your bicycle knowledge, and ideally a local cycling Friend to help and advise you, you might consider buying a bike locally for an overseas tour.

This is essentially the cycling counterpart to the common practice of buying a second-hand motor vehicle for a road trip across North America or Australia, and selling it at the end of your trip. If you are both savvy and lucky, you might get a bike cheaply enough (even counting the cost of modifications, upgrades, and repairs), and recover enough of the price when you sell it, for your net outlay to be less than the cost of shipping a bike there and back home again.

Buying a bike on arrival is most likely to work out if (1) you have relatively “standard” proportions; (2) you are relatively tolerant of less than optimal bicycle sizing, fit, and component choices; and (3) you are spending some time at the start of your trip, before you plan to start riding, in a place where you have confirmed in advance (through that local Friend I just mentioned, or perhaps through a local bicycle touring club or the like) that suitable bikes, in suitable sizes (are you much larger or smaller than most people and bikes in the place where you are going?) are likely to be available for an acceptable price.

Ask locals where used bikes for sale are advertised: Craigslist in the USA, Gumtree in the UK, mailing lists and bulletin boards of cycle touring organizations like CTC in the UK or ACA in the USA, etc. Check sample prices and availability in advance, online and/or by phoning used-bike dealers.

Keep in mind that asking prices may be negotiable but that the condition of used bikes may be worse than you expect from advertisements that depict them in the most favorable light. The best prices may be for bikes that are available only on a cash-and-carry basis and have to be picked up in out-of-the-way places that are far from any city and hard to get to without a car.

Expect it to take some time — longer than it would at home, where you know where and how to look — to locate the right bike for sale at the right price, and to configure it and get all the necessary accessories. (Bring as many of these with you as you conveniently can.)

The ideal seller is someone who has just finished their own bicycle trip in the opposite direction, and is selling a completely equipped and “broken-in” touring bike rather than paying to take it home with them or on the next leg of their journey. You can’t count on finding a seller like this, but it’s not unusual to see ads in the hostels or on Craigslist in gateway cities like San Francisco from foreign visitors who are selling their bikes at the end of North American journeys, before flying on (without their bikes) to Australia, Asia, Latin America, or Europe. Someone like this is likely to sell you a bike that you can be ready to ride almost immediately, and may include racks, panniers, tools, spares, etc. for very little, if anything, more than the price of the bare bike.

Bringing or shipping your own bike

Most people who already have a touring bike they like would prefer to have it with them wherever they ride (unless local road conditions require a different bike, such as one with wider, softer tires for unpaved roads). Unfortunately, taking your bike by plane with you has gotten much more complicated and often much more expensive than it used to be. Worst of all, it has become impossible to predict how much that will cost.

Every airline has different rules and fees for transporting bicycles. Check directly with each airline for current rules and fees. Because these change often, all third-party summaries and sources of information about different airlines’ rules and fees for transporting bicycles are unreliable, and many authoritative-looking ones are wrong. Don’t rely on what someone else says they paid. Not only may the rules and/or fees have changed recently, but they can vary, even on the same airline, depending on the route, the direction of travel (like fares, fees can be different in opposite directions), and the fare paid.

Baggage fees — including fees for excess, oversized, or overweight items — are an increasingly important profit center for airlines, which are trying as hard as they can to make sure that they charge each passenger as much as they are willing to pay for their luggage, and no less. Airline rules and fees for carriage of bicycles are complex and ambiguous, especially where a single journey involves connecting flights operated by multiple airlines, or a codeshare flight ticketed with one airline’s flight number but operated by another.

Your interpretation of the tariff may not be same as that of the airline staff at the check-in counter. If you don’t pay what they demand, you and/or your bike won’t be transported. Once you have handed over cash or signed a charge authorization for the baggage fee, you have little chance of ever getting it back.

The worst case — for which you have to be prepared — is to be hit up for a substantial unexpected surcharge (US$200 would not be unusual, especially for an intercontinental flight, and it could be even more) when you go to check your bicycle in for your return flight.

In 1985, when I moved from Boston to San Francisco, I wheeled my bicycle up to the check-in counter at Logan Airport, turned the handlebars, and handed it over to People Express. At SFO, I straightened the handlebars and wheeled it away from the oversized baggage claim office. I think I paid a handling fee of US$5.

Some airlines, on some routes, still accept unboxed bicycles like this. Others only require bikes to be wrapped in giant plastic bags, which they provide. Most, however, require bikes to be packed in boxes of some specified maximum size, which size varies from airline to airline.

Boxing a bike to take on a plane is a nuisance at best, and requires some skill. How much you have to disassemble the bike varies with the size and style of the frame, size of the wheels, style and size of the racks and other protruding accessories, and size of the box.

You have to pad the parts of the bike against rattling around and scraping or denting each other, as well as against getting crushed if the box is piled on its side under other luggage. The components most commonly damaged in shipping are, in order of frequency, rear derailleurs, rear derailleur hangers, brifters, and spokes. I strongly recommend always removing the rear derailleur for shipping. Wrap it well and zip-tie it inside the frame where it can’t shake loose or damage itself, the frame, or other parts. A bent derailleur hanger is common after shipping a bike. It’s scary, but usually pretty easy for a bike shop to bend back into alignment with the proper tools. (In a pinch, you can do it yourself with cruder tools, but don’t try it unless you know what you are doling!) I don’t recommend brifters for travel, because of their fragility and the difficulty of repairing them yourself on the road. But if you do ship a bike with brifters, remove them for shipping or pack them with as much protection as you can manage. Broken spokes are repairable, but likely to delay you while you wait for repairs if you can’t find a bike shop with the proper spokes in stock. Carry a Fiberfix or similar spoke repair kit; think about possible sources of spoke breakage as you arrange your frame, wheels, and other components in the bike shipping box; and consider boxing your wheels separately if they are especially fragile.

Because they contain large metal tubes that are obvious on x-ray images, bike boxes are often opened for “security” inspection — and carelessly or ineptly repacked. Unless you pay a fortune for insurance, airlines will only accept bicycles as luggage if you absolve the airlines, in advance, of any liability for damage in transit, even damage from their negligence.

Within the USA, this leads many cyclists to ship their bikes by Amtrak, UPS, or Fedex ground, rather than by air. Ground shipping is slower, obviously, but surface shipments are much less likely to be opened for inspection or damaged in transit.

If you don’t want to disassemble or reassemble your bike yourself, or don’t feel competent to do so, you can have a bike shop box (and ship) it for you, and/or ship it or take it to a bike shop to reassemble for you at your destination — for a price, of course.

With limited exceptions, as of this writing, you can only take bicycles with you on Amtrak, or ship them as unaccompanied Amtrak Express rail freight, between Amtrak stations with checked baggage service. Between stations with baggage service, however, Amtrak offers by far the best deal in the lower 48 US states for long-distance bicycle shipping, for two reasons:

First, Amtrak allows you to use larger boxes (which they supply for $15 at their baggage offices, although you need to reserve them in advance) than any airline. That means that even with larger bikes with fenders and racks, you probably won’t have to remove the wheels or do anything more than turn the handlebars and maybe remove the pedals.

Second, Amtrak charges less for bike shipping than any other shipping service. You can take a bike with you as luggage, between any Amtrak stations with checked baggage service in the lower 48 US states, for US $10 (plus the $15 cost of the box, if you don’t have your own box).

[Update: Amtrak discontinued all of its shipping services for unaccompanied packages or freight, including unaccompanied bicycles, during the COVID-19 pandemic, and as of 2024, has not resumed these services. Since 2020, you can only ship a bike by Amtrak as accompanied baggage. In the absence of Amtrak as an option, I’ve found Bikeflights.com to have the lowest prices for shipping boxed bicycles within the USA. Bikeflights.com has wholesale contract rates with UPS, Fedex, and other surface and air freight companies, and resells their services for significantly less than you would pay as a direct retail customer of the same carriers. I’ve used Bikeflights.com several times without problems, each time paying around US$100 to ship a boxed bike coast-to-coast in about a week.]

Break-apart and folding bicycles

Some bicycles are easier than others to transport on planes, trains, and buses than others.

Otherwise standard-sized bicycles can be built with couplers or fittings that enable them to be separated into two parts, to fit in significantly smaller boxes or cases. S & S couplers are available as an added-cost factory option with most custom-made steel frame bicycles and a small but growing number of production or semi-custom bicycle models. (They can also be retrofitted into existing frames, although that is rarely worth the expense.) A few frame builders use the alternative Ritchey breakaway system or other joining mechanisms to enable a full-sized frame to be separated in half for shipping.

Taking apart or putting together a break-apart bike isn’t a trivial task. I haven’t done it myself, but people with bikes like this report that even with practice it takes them 30-60 minutes to disassemble and pack, or unpack and reassemble, their bike.

At current prices, S & S couplers add a minimum of US$600 to the price of a bike. That’s a lot, obviously. But if couplers enable you to fit your bike into a sufficiently smaller box or case to reduce the shipping charges substantially, they might pay for themselves in as few as two or three round-trips by air. Unfortunately, shipping charges are sufficiently uncertain that it’s difficult to predict whether couplers will turn out to have been worth the price.

If you are going to the trouble and expense of getting a custom-made touring bike, that’s probably the bike you will want to use for any overseas long-distance tour. I would consider having couplers included in any new custom or high-end touring bike, if they are an option.

If you want to be able to pack and unpack your bike more quickly, and fit it in an even smaller case or box, you can get a “folding” bike with smaller wheels and a hinged, compact frame. A folding bike typically fits into a case that’s small enough to be carried as a normal item of luggage, and can be folded and unfolded in just a few minutes. You can even carry some folded bicycles onto a train by hand, without a case, and stow them in the regular luggage racks.

Most folding bikes are designed and sold primarily for short-distance commuters, to carry on and off trains and buses to cover the “last mile”. A few folding bikes, however — including some of the models from Bike Friday, Birdy, and Moulton — fold almost equally small (if sometimes a bit more slowly, given their greater complexity) but are designed for long-distance touring, with fenders, racks for panniers, and a range of gears comparable to that of a full-sized touring bike.

I’ve test-ridden a Bike Friday, and didn’t find the ride remotely comparable to that of a full-sized bicycle. A small-wheeled bicycle cries out for a suspension, and the Birdy (expensive) and Moulton (even more expensive) I’ve tried out were much more comfortable and better handling. Your mileage may vary: I’ve met people who find their folding bicycles (including Bike Fridays) as comfortable for long-distance touring as any other touring bicycle. If you find the ride adequate, a folding bicycle makes it possible to travel in a very different way, mixing travel by bicycle, train, bus, and plane.

International differences in bicycles

Road and trail conditions and road-use cultures make different bicycles optimal in different countries. Are the roads you will be riding likely to be asphalt, gravel, or dirt? Do you have good enough maps to know whether a route you choose will turn out to be paved? Is something called a “bike path” likely to resemble a road for motor vehicles or a hiking trail?

Crazyguyonabike.com has a huge collection of bicycle travel journals from all over the world, so there’s a good chance that you can find someone else’s report on what type of bike they used, and what the roads and riding were like. As you read other travellers’ stories, keep in mind that tastes vary: Some people would choose a full-suspension balloon-tired “mountain” or “trekking” bike for a trip across the USA, while others would prefer a “road” bike with narrower, smoother, higher-pressure tires.

Other than that, the most important differences in bicycles from country to country are in terminology and in the sizes of wheels, rims, tires, and tubes.

La langue du vélo (“The tongue of the velocipede”, or the language of the bicycle)

Almost all bicycling hardware intended for international markets is labeled in English, French, and/or German. If you already know English, French bicycle lingo is the most important to learn. Most German (and Dutch, etc.) cycling gear is also labeled in English (and/or French), while a fair amount of cycling equipment is labeled only in French, reflecting the special place of cycling in French culture and of France in the cycling world.

The German word for bicycle is “Fahrrad”, which always makes me think of “far-ride” although I’ve read that the actual etymology is completely different. The Dutch word for bicycle is “fiets”, which I’ve read is derived from the word for a “surrogate” or “ersatz” horse.

I know enough French to be a bit more precise: bicycle travel is “cyclotourisme”, a touring or travel bike is a “vélo de voyage”, and the ideal shop for a bicycle traveller (few and far between, even in France, although ordinary bike shops are common), is a “magasin specialisé en vélos de voyage”.

General-purpose phrasebooks don’t usually include cycling-specific vocabulary. If you are travelling by bike abroad with any sort of electronic device, I would download and take with me all of the following. They overlap in part, but each has some words and phrases the others lack:

• Sheldon Brown’s English-French and French-English bicycle dictionaries
• Sheldon Brown’s English-Spanish and Spanish-English bicycle dictionaries
• Vocabulaire panlatin du vélo from the “Office québécois de la langue française”, the Québécois counterpart of the Académie Francaise (includes all the major Latinate/Romance languages, even Catalan, Romanian, Galician, etc.)
• ADFC (German cycle touring club) dictionaries: English-German, German-English, French-German-English (much better for German than French, naturally)
• Park Tool’s Bicycle Mechanic Languages Spreadsheet (not always as accurate, but includes German and Dutch among other non-Latinate languages)

What sizes of wheels, rims, tires, and tubes are best for international travel?

If you don’t want to read the rest of this section, here’s the short answer:

The only bicycle rims and tires that are readily available worldwide are the ISO 559 (26”) size that is standard on “mountain” bikes. The most common tires in this size are nominally 2.25 inches wide, so make sure your rims will fit tires of this width if you want the best chances of finding a replacement. Almost all common tubes for bikes this size use larger-diameter Schrader (not the narrower Presta) valves. So make sure that the valve stem holes in your rims are large enough for Schrader valve stems, even if you normally use Presta valves.

Beyond that, things get complicated and confusing.

The specifications and labeling of bicycle wheels, rims, tires, and tubes are ambiguous and inconsistent. Five incompatible sizes are labeled and sold as 26” tires, for example. You might find two of them side-by-side at Walmart! The only unambiguous denominations are the ISO (International Organization for Standardization) or ETRTO (European Tyre and Rim Technical Organisation) numbers, but not all labeling, packaging, or product listings include the ISO/ETRTO numbers. For the gory details, see Sheldon Brown’s definitive treatise on bicycle rim and tire sizing and labeling.

To make matters worse, a lot of authoritative-seeming advice about bicycle tire availability, even in otherwise reliable books and Web sites, is simply wrong. Most often, that happens because bicycle experts, who buy their bicycles and bicycle tires at bike shops, forget that the overwhelming majority of bikes and bike tires, in the USA or abroad, aren’t sold at bike shops.

There are good reasons to dismiss, or at least to recommend against buying, department-store bikes, as I discussed last week in my FAQ on buying a touring bicycle. But when it comes to spare tires or replacement rims or wheels in case of a breakdown, what matters most is what’s in stock at mass-markets retail outlets.

If I blow a tire in the middle of Nebraska, or shred it on a piece of broken metal that fell off a truck onto the shoulder of the road, I don’t want to have to hitchhike 200 miles (300 km) to the nearest bike shop. I want to know whether I can find a replacement tire (or, in case of a more serious problem, a replacement rim or wheel) at the local Walmart, Kmart, Target, or the like.

Mass-market bikes often use different wheel and tire sizes than bike-shop bikes. Bikes last a long time, and mass-market retailers stock tires and tubes for the bikes people ride. That includes sizes for bikes that are no longer being made and that bike shops consider “obsolete” but that were produced in large numbers and remain in common use. People who don’t regularly ride a bike with 27” (old road and touring bikes) or 650A (Raleigh three-speeds) wheels may have no idea what tires are available in those sizes, or how easy they are to find.

So far as I can tell, for example, no new bikes with 27” wheels have been made or sold, anywhere in the world, for about 20 years. Millions of bikes like this, perhaps ten million, are still in use, however, and you can buy replacement tires for them in any Walmart in the USA, Canadian Tire in Canada, or Halfords in the UK and Ireland. You can get cheap Chinese store-brand tires in this size, or anything up to the highest-quality Japanese or German tires. (My favorite 27” tires for touring are Continental Gatorskins, which ironically are made in Germany but unavailable in Germany except by mail or by special order.) A few years ago a Chinese company tooled up to start making quality replacement rims in this size.

Since I couldn’t find an international table of bicycle tire-size availability, I’ve compiled the one below. For each country, group of countries, or region, I’ve listed bicycle tire diameters in order from the most commonly available to the hardest-to-find. I welcome criticism and suggested additions and amendments in the comments.

• USA, Canada, UK, and Ireland:
  
  Available at Walmart, Canadian Tire, Halfords (UK and Ireland), and other toy stores, department stores, etc.:
  
  1. ISO 559 (26”) - “Mountain” bikes (also available at bike shops)
  2. ISO 406 (20”) - Most BMX bikes and many other children’s bikes (also used on some folding and recumbent bikes)
  3. ISO 630 (27”) - Most 1970s-1980s “ten-speeds” and other road/racing and touring bikes (more common in the USA and Canada, but also available in the UK and Ireland)
  4. ISO 590 (650A, 26” × 1 3/8”) - Formerly used on Raleigh 3-speeds and many other bikes sold through the 1970s, and still used on many wheelchairs (more common in the UK and Ireland, but also available in the USA and Canada)
  5. Various other sizes used on children’s bikes
     
     Available only through bike shops (or by mail):
     
  6. ISO 622 (700C or 29”) - The most common size for new “road” (racing/sport) and some touring and “mountain” bikes (beginning to be available at Walmart and the like, but only to a limited degree, and only in knobby styles and sizes too wide for most touring bikes)
  7. ISO 451 (20”) - Much less common BMX wheel size (also used on some folding and recumbent bikes)
  8. Other sizes (650B, etc.) - Rarely in stock but anything is available by mail order
     
     
• Continental Europe:
  1. ISO 559 (26”) - “Mountain” bikes (available everywhere)
  2. ISO 622 (700C or 29”) - Available at all bike shops, but generally only at bike shops
  3. Other locally popular (or formerly so) variants
  4. Other sizes available by special or mail order
     
     
• Japan:
  1. ISO 590 (650A, 26” × 1 3/8”) - Used on most mamachari and many other utility, road, and randonneur bikes
  2. ISO 559 (26”) - “Mountain” bikes
  3. ISO 622 (700C or 29”) - “Road” (racing/sport) and some touring and “mountain” bikes
  4. Other sizes available by special order
     
     
• China, India, Africa, and the rest of Asia (except Japan):
  1. ISO 635 (700B or 28 1/2”) - Chinese, Indian, and English single-speed “roadsters”
  2. ISO 559 (26”) - “Mountain” bikes
  3. ISO 622 (700C or 29”) - Sometimes available at bike shops in major cities
  4. Any other size is likely to involve international mail ordering (e.g. from the USA or Europe), and potential long delays, import duties, and customs hassles
     
     
• Mexico and Central and South America:
  1. ISO 559 (26”) - “Mountain” bikes
  2. ISO 622 (700C or 29”) - Sometimes available at bike shops in major cities
  3. Any other size is likely to involve international mail ordering (e.g. from the USA), and potential long delays, import duties and customs hassles.
     
     

Overwhelmingly the most common bicycle wheel and tire size in use in the world today is the ISO 635 (700B or 28 1/2”) size used on single-speed “roadsters”. Perhaps a billion bikes with wheels this size have been turned out over the last century by vast vertically-integrated manufacturers including Flying Pigeon (Tianjin), Forever (Shanghai), and Phoenix (also Shanghai) in China, Hero Cycles (Ludhiana, Punjab) in India, and Raleigh (Nottingham, England) in the UK. Perhaps a hundred million of these bikes are still in use today, and tires for them are available in every village shop in countries where they are common. But there are other vast areas of the world where bikes or tires like this are utterly unknown.

The only bicycle tire and wheel size you can count on finding in any country worldwide is ISO 559 (26”), the size used on most “mountain” bikes from the cheapest to the most expensive. [I’ve been told that the ISO 406 (20”) size that’s the most common for BMX and other children’s bikes is also available anywhere there are child-sized bicycles, although I haven’t done enough research to be sure about this.]

All these details could change. Eventually, tires in sizes in which no new bikes are being made, such as ISO 630 (27”) will get harder to find. Other tire size may be resurrected or become more common. 700C wheels, once used only on high-end skinny-tired racing bikes, are now being used on some “29er” mountain bikes and are beginning to enter the mass market on “hybrid” bikes. ISO 584 (650B) rims and tires have recently acquired a niche following for randonneur and touring bikes, and are beginning to be tried out on mountain bikes. (Some people have argued persuasively that it would have made more sense for evangelists of 650B to promote the very close, but incompatible, 650A size, which is currently much more widely available. But that hasn’t happened.) These trends may or may not continue and lead to more widespread availability of tires in these or other sizes.

Only the ISO specifications are unambiguous. For example, a mountain bike wheel, rim, or tire described as 27 1/2” is probably a 650B. Such a 27 1/2” mountain bike wheel is in between the mountain bike wheel sizes described as 26” (ISO 559) and 29” (ISO 622). But 27 1/2” and 29” mountain bike wheels are both smaller than 27” (ISO 630) road and touring bike wheels.

Tubes and valves: Presta or Schrader?

As you would expect, tubes are typically available to fit whatever sizes of tires are most common, as tabulated above. Local availability of tubes is far more important than that of tires. High-quality tires last a long time, and you can usually tell when they are beginning to show wear and you need to start looking for a replacement. A damaged tire can usually (although not always) be rendered rideable, at least for long enough to get a replacement delivered or get to a place where one is available. Tubes, on the other can, can get cuts so large that they are impossible to patch, or fail at the valve or valve stem. In my experience, flats tend to come in bunches: I can go months without a flat, then get four in a day.

Tubes stretch, so you can use a tube that’s made for a smaller wheel or narrower tire in a slightly larger or fatter tire. So, for example, you can use 700C x 25mm tubes in larger diameter and width 27 × 1 1/4” tires, or 26” mountain-bike tubes (if they are narrow enough) in 650B tires. A stretched tube gets a little thinner and easier to puncture, but it’s not a big deal.

It doesn’t work the other way, however: If you try to fit a larger tube in a smaller tire, it’s likely to get bunched up in such a way as to cause pinch flats. You can’t fit a tube made for a 700C x 45mm comfort or hybrid bike or a “29er” mountain bike (the only type opf Presta-valve tube you are likely to find at Walmart) into a 700C x 32mm touring-bike tire.

Travelling bicyclists most often have problems finding tubes if either (1) they have narrower tires than any of the locally-available tubes, or (2) their rims are drilled for Presta valves, but the only available tubes have Schrader (or Woods/Dunlop) valves.

Schrader valves are the type used on car and truck tires. Presta valves have narrower stems and a different type of valve and fitting. Each type has advantages and disadvantages. I have bikes with both types. For international travel, the decisive thing is that you can use Presta tubes (with tiny metal or rubber adapter sleeves, or without the adapters in an emergency) in rims drilled for Schrader valves, but you can’t fit a Schrader valve stem through the smaller hole in a rim designed for Presta valves without drilling out the hole.

If your pump breaks — and bicycle tire pumps can and do fail without warning — you can use a gas-station air pump to inflate Shrader valve tubes, as long as you are very careful not to over-inflate them. You can only inflate Presta-valve tubes with a gas-station air pump if you have the proper adapter. Presta-to-Shrader adapters are small and inexpensive, but they are rarely available locally in places where you might need them. Carry one or two if you are touring with Presta-valve tubes.

It’s not unusual for a desperate cyclist to have to drill out their rim in the field if they run out of patchable Presta tubes and find that only Schrader-valve replacements are available locally. If you might have to have your rims drilled, better to plan for that and have it done carefully before you leave. Your local bike shop might think that it’s heresy to deliberately do something that will weaken your rims, but it’s actually a common practice to drill out rims before a tour in a region where Presta tubes may not be readily available.

Enlarging the valve hole weakens the rim, obviously, so make sure you start out with a sufficiently wide and strong rim, preferably with a “boxy” cross section so the valve doesn’t need a long stem. Deep V-shaped rims that require long-stemmed tubes may not be usable with Schrader valves even if they are drilled out to Schrader diameter, since most Schrader-valve tubes have short valve stems.

Most tubes made for 700B single-speeds or Japanese 650A bikes, as well as many Dutch bikes, use a third type of valve, the Woods or Dunlop valve. I’ve ridden bikes with these valves, but I’ve never had to fit a new tube of this type. In a pinch, I’ve read that you can fit one of these tubes (if it’s close enough to the right size) in a rim that’s drilled large enough for Schrader valves, and inflate it with a pump that’s made for Presta valves or by using a Presta-to-Schrader adapter.

Bonne voyage, et bonne randonnée (happy riding)!