Basic Motorcycle Knowledge: Summary of Motorcycle Knowledge When Choosing a Motorcycle (Engine Edition)

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What are the advantages and disadvantages of the riding quality of a motorcycle depending on the number of cylinders?

It's no exaggeration to say that motorcycle's riding quality is determined by its engine. The bigger the engine displacement, the more powerful it becomes, and the heavier the motorcycle is, the more imposing the ride becomes, as befits a larger motorcycle.

However, there is another important factor. It is the difference in the layout (arrangement) of the engines. Specifically, the number of cylinders and the arrangement. I would like to see what features and benefits each layout has.

Single-cylinder: If you want to enjoy simplicity and a sense of excitement.

The single-cylinder featured a one-shot explosion that clearly conveyed with a thudding exhaust sound. The riding quality is described as pleasant or idyllic, and the advantage is that a simple structure makes it a lightweight and slim body. Therefore, it is often used for small engine displacement and off-road models and is also widely used for practical motorcycles such as scooters and "Super Cub" because it can be made cheaply. In addition, this is a layout suitable for style-oriented neo-classics.

On the other hand, it is difficult to raise the rev and there is a limit to the amount of power, and the larger the engine displacement, the greater the vibration tends to be. Typical models include the SR400 and CRF250M.

SR400
YAMAHA SR400
CRF250M
HONDA CRF250M

2-cylinder: A standard balance of style and performance.

The 2-cylinder has an efficient and well-balanced layout. The exhaust sound is unevenly spaced or has a fine thudding sound, and it has a sense of "kicking off the road" or "excellent traction". It's hard to say this because the feeling varies greatly with the ignition sequence and ignition interval, but for example, the 270-degree crankshaft, which is popular in recent parallel twin-cylinders (parallel twin), is said that the use of unevenly spaced explosions enhances the feeling of pulse and traction (the sensation of the tires catching the road surface) like that of a V-twin.

There is also a minority "vertical engine", such as BMW and MOTOGUZZI, in which the crankshafts positioned vertically in relation to the motorcycle body. In this type of design, the cylinders are distributed to the left and right to achieve a low center of gravity, and since the crankshaft faces the same direction as the vehicle body, the inertia of the crankshaft makes it easier to tilt the engine to the left or right. The recoil of crank rotation (so-called torque reaction) tends to cause the body to tilt to the right or left when the accelerator is turned on, which is also a maniacal feature.

The 2-cylinder layout is widely used from small to large engine displacements, from sports models to cruisers, and it can be said that it has the widest variation among motorcycle engines. Typical models include the DUCATI and V-Strom series, which are famous for V-twins, as well as the new "Africa Twin" and "MT-07", which are parallel twin-cylinder models.

V-STROM650
V-twin SUZUKI V-Strom 650/XT
CRF1100L
Parallel twin-cylinder HONDA CRF1100L Africa Twin

3-cylinder: Taking the best combination of both 2-cylinder and 4-cylinder

The 3-cylinder is often referred to as a good combination of 2 and 4-cylinders, as it has an intermediate feeling between the 2 and 4-cylinder engines, and has a sense of both throbbing and a sense of rising smoothly. Parallel 3-cylinders are the mainstream, and the advantage is that it can be built more compactly with 4-cylinder power.

The output characteristic is basically flat and has torque in the mid-range, and the sound is thicker than a 4-cylinder and finer than a 2-cylinder, and there are many types of smoothness and fine throbbing in the middle. The main type of ignition interval is the 120-degree crank, which divides 360 degrees equally into 3 parts, and the smooth rotating feel of equally spaced explosions is very attractive. It is sometimes compared to a rotary engine.

Typical examples of this type of cruiser include the Triumph "Triple" series and the MT-09. Strangely, Rocket 3, which is also Triumph's largest cruiser in the world, uses 3 vertically arranged cylinders.

SPEEDTRIPLE
Triumph Speed Triple/Street Triple
MT-09
Yamaha MT-09

4-cylinder: The power to penetrate up to high rev is very attractive.

The 4-cylinder is characterized by a high-pitched, siren-like exhaust sound and rising sensation like chest-pounding. In general, the more cylinders you have, the smoother the rotation, and the more efficient the layout can be extracted at higher rev. The most common ignition interval is 180 degrees, with 2 of the 4-cylinders in the middle and 2 on each side of the set exploding at equal intervals. It is also synonymous with high-performance engines, and most high-performance machines, such as the Super Sport using 4-cylinders.

Japanese motorcycles have traditionally been strong, but the feeling is also quite different between a parallel 4-cylinder (inline-4) and a V-type V4 cylinder. Roughly speaking, the inline-4 has more high-revving power, while the V4 has superior mid-range torque. On the other hand, the V4 has the advantage of being able to make the width of the body narrower, but it also has the disadvantage of increasing the number of cylinders, which complicates the mechanism, increases weight, and increases production costs. This is why 4-cylinders are often used in large-displacement models and high-end models. The "Super Sports" and other representative models of various manufacturers are almost all 4-cylinder models.

CBR1000RR
HONDA CBR1000RR SP with parallel 4-cylinders
TuonoV4
V-type 4-cylinder Aprilia Tuono V4 1100 Factory

6-cylinder: Superb ride unique to Silky 6

The 6-cylinder is known as the Silky Six, and its rotational feel is smoother and softer than that of a 4-cylinder. Therefore, it is often used in large-displacement tourers such as BMW's K series, the former Z1300, and CBX1000. HONDA "GOLDWING" has traditionally followed the unique layout of an opposed 6-cylinder placing horizontally and vertically. As you can see from the 4-wheelers, the more cylinders you have, 6, 8, and 12, rather than 4, the more premium and upscale the model becomes.

However, since it becomes larger and heavier, there is a limit in the case of a motorcycle where a rider straddles and controls directly. So, the 6-cylinder is the largest class of current mass-production models, and it is only used in the aforementioned flagship tourer.

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▲Horizontally opposed 6-cylinder GOLDWING

You can choose according to your objective, purpose, and preference.

Even if the engine displacement is the same, the riding quality will change greatly depending on the number of cylinders, and its arrangement. It's interesting to consider not only the engine displacement and type of motorcycle but also the engine layout.

For example, middle-class motorcycles are very popular these days, but with the MT-07 (parallel 2-cylinder) and CB650R (parallel 4-cylinder) both having roughly similar displacements, many people are wondering which one is better for them. A hint is that the MT offers a spirited, responsive throbbing, easy power, and light handling, while the CB offers an exciting high-revving sound and the kind of power you'd expect from a big motorcycle, but with heaviness. You'll find that each one has its own unique appeal. Now you can choose your favorite motorcycle according to your own preference and objectives.

MT07
Parallel 2-cylinder YAMAHA MT-07
CB650R
Parallel 4-cylinder HONDA CB650R

See HONDA Moto Index Page
See YAMAHA Moto Index Page
See DUCATI Moto Index Page
See Accessories for HONDA CB650R
See Accessories for YAMAHA MT-07 (FZ-07)

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