Head-To-Head: Brompton vs. Road Bike

Commuting via bicycle in a large urban area often makes quick work of an otherwise dull journey. Added benefits include exercise and fresh air as you coast seamlessly down the packed boulevards or empty side streets.  

Then, reality begins to set in as you struggle to find a place for your bike on the train or bus. Paranoia creeps up as you walk away from your locked bike, uncertain if it will be there when you return. These reasons explain the soaring popularity of the Brompton bicycle. These nifty little folding bikes make urban commuting a breeze and make transitioning to the train or office a simple task. 

Even at a glance, one can see that riding a folding bike is an entirely different experience. You’ve been commuting with your road bike for years, and know precisely how it rides. You’re a little unsure about how a tiny folding bike might handle the ride that you’re so familiar with.

Just how vast is the difference between riding a compact folding bike versus a full-sized road bike? Let’s add up the main differences between the two types of bikes and see who comes out on top and under which circumstances.

Folding and Compact Size

Folding is the bread and butter of the Brompton bicycle. These bicycles are consistently ranked the best folding bikes on the market.  Crafted in London using lightweight high-quality parts in an incredibly small package is what earns their praise. Wherever you go, so too does your Brompton bicycle, whether that be the office, classroom, or an airplane. 

Road bikes, on the other hand, are not known for their folding ability. Single speeds, high or low-end road bikes, and TT bikes are all large and flashy. Trying to squeeze them on a train draws the ire of all those around you during rush hour. Bringing your road bike inside can be obnoxious due to just how much space it takes up. 

In contrast, the Brompton comes equipped with tiny wheels which are only 16 inches. Road bike rims are almost double (622 mm vs. 349 mm) the diameter of the Brompton bike. This difference has a significant effect on the riding style due to a few physical principles. 

Speed

The Brompton bicycle won’t win any road races, but it isn’t the slowest bike on the road either. Small tires have the advantage of making it effortless to get going from a complete stop. This is due to smaller wheels having a lower moment of inertia, which makes accelerating quick and easy. So, the Brompton excels at continually starting and stopping at red lights. Only a little bit of energy is required to get the Brompton off the line and comfortably moving along.  

These tiny wheels also carry much less momentum than full-size tires, however.  To maintain a higher speed, you need to keep pedalling. If you stop turning the crank to coast on a flat road, you’ll notice how quickly you lose speed. With that said, the Brompton can go as fast as they are geared — just because they can fold does not make them slow. 

Road bikes have large wheels and greater momentum, giving them the opposite effect of the Brompton. Starting from a complete stop is slower and takes much more energy. After you spin up, keeping that speed is done without much effort due to this momentum and the fact that most road bikes (excluding single speeds) are geared much higher. 

Aerodynamics also plays a vital role in speed. Aerodynamics can change depending on the form of a rider. On a Brompton, you are most likely to be sitting upright and comfortable which is a less aerodynamic position. On a road bike, especially with drop handlebars, an aero or forward-leaning position is favoured. While not playing a huge role, this difference may have an effect on speed, especially at higher cadences. 

Handling

Once again, the small wheels on the Brompton influence the way the bike handles. There’s a much more focused area of contact with the road. This results in a smaller area of weight distribution within the wheel. The sum of all this technical jargon is that the handling is very sensitive. Weaving in and out of traffic is fine, but it would be wise to keep both hands on the handlebars at all times. Speed amplifies the problem, so the faster you go, the more twitchy the handling becomes. 

Handling a road bike is much more stable due to larger wheels. Zigzagging around traffic and all over the road may not be as easy as on a Brompton. This only applies to small spaces though, since a road bike isn’t difficult to manoeuvre at all. The incredible stability the large wheels offer allows you to be comfortable on the handlebars even at high speeds. If you have to deal with a lot of hills and higher velocities, a road bike may be a safer option. 

Ride Quality

The Brompton’s tiny wheels amplify the road’s imperfections — a big pothole may pose an actual threat on a Brompton. These problems are offset by being equipped with a suspension system. The suspension consists of a polyurethane block that smooths out some of the lumps and bumps. Still, you may notice a bit of a sore back as you get used to riding your Brompton folding bike.

Despite not having a suspension system, road bikes can handle most small bumps on the road. A sizeable pothole will still do some damage, but you’re more likely to come out of it in one piece on a road bike. Depending on the handlebars, sitting in an aero position or leaned over your drops may not be the most pleasant way to ride. 

Wrapping It Up

The most significant difference between the Brompton folding bike and road bikes is the size of the wheels. This size difference slightly changes the riding characteristics that you might be used to. Each riding style has its advantages and disadvantages depending on the situation. 

On a road bike, you will most likely be riding with friends, getting Strava KOMs, and setting records. On a Brompton bike, you’ll be casually traveling to meet with friends or commute to work. What works best depends on the situation, and both riding styles reflect that idea completely.