25 Motorcycle Engine types

As the Workshop Manager at Naked Racer Moto Co and with over 35 years of hands-on experience in the motorcycle industry, I’ve worked on everything from vintage classics to modern sport bikes, custom builds, and touring machines. Over the decades, I’ve seen how different motorcycle engine types shape the way a bike feels, performs, and connects with its rider. In this guide, I’ll share my knowledge of 25 distinct motorcycle engine designs, blending technical insight with stories from the workshop floor — whether you ride for racing, adventure, commuting, or the love of classic two-wheel engineering.

1. Single‑Cylinder (Thumper)

A single-cylinder engine, often called a “Thumper” due to its distinct rhythmic exhaust note, is the most basic type of motorcycle engine. As the name suggests, it contains only one piston inside one cylinder that moves up and down to power the motorcycle. This engine completes all four strokes (intake, compression, power, and exhaust) using just one cylinder.

Simplicity is its greatest strength. Fewer moving parts mean it's lighter, easier to maintain, and less expensive to build. Single-cylinder engines are widely used in entry-level motorcycles, off-road bikes, commuters, and classic motorcycles. While they don’t offer high top-end speeds or the smoothness of multi-cylinder engines, they deliver instant low-end torque, making them punchy and responsive in city traffic and dirt trails.

However, they can vibrate more at higher speeds and may feel a bit rougher compared to twins or inline-fours. That said, many riders appreciate the raw, mechanical feeling that a Thumper provides—making it a favorite among purists, adventurers, and practical daily commuters.

Key characteristics of single-cylinder engines:

Lightweight and compact
Simple maintenance and fewer parts
Strong torque at low RPMs
Ideal for dirt, trail, and beginner bikes
Common in 50cc to 650cc motorcycle classes

Historic and popular motorcycles with single-cylinder engines:

Harley‑Davidson F‑head Single (1903–1909)
Triumph Model H “Trusty” 550 cc (1915–1923)
Indian Single 303 cc (1907)
BMW R24 / R25 Single (1948–1953)
BMW R27 247 cc Shaft-Drive (1960–1966)
Honda XR650L (1993–Present)
KTM 690 Enduro R (2008–Present)
Royal Enfield Himalayan 411 (2016–2024)
Suzuki DR-Z400S (2000–Present)
Yamaha XT500 (1976–1989)

2. Parallel Twin (Inline Twin)

A parallel twin engine, also known as an inline twin, features two cylinders mounted side by side in a single row. Both pistons move up and down together or in alternate patterns depending on the crankshaft configuration. This design offers a good balance between simplicity, smoothness, and power, making it one of the most widely used engine layouts in modern motorcycling.

Parallel twins are compact and easier to fit into various motorcycle frames, especially compared to wider V-twins or inline fours. They typically offer more power and refinement than single-cylinder engines while remaining lighter and more affordable than larger multi-cylinder designs. Engine smoothness can vary depending on crankshaft setup—such as 180°, 270°, or 360°—each offering different performance and sound characteristics.

This engine type is favored in commuter bikes, touring machines, modern classics, and even beginner sport motorcycles. It’s a practical middle ground offering versatility and strong mid-range performance, with decent fuel efficiency and reliability.

Key characteristics of parallel twin engines:

Two cylinders mounted side by side
Compact and fuel-efficient
Smoother than single-cylinder engines
Flexible for touring, city, and sport use
Crankshaft type affects vibration and character

Historic and popular motorcycles with parallel twin engines:

Triumph Speed Twin 500 (1938–1966)
Norton Dominator 88 (1952–1966)
Honda CB500T (1975–1976)
Kawasaki KZ400 (1974–1984)
Yamaha XS650 (1968–1985)
Kawasaki Ninja 650 (2006–Present)
Yamaha MT-07 / FZ-07 (2014–Present)
Royal Enfield Interceptor 650 (2018–Present)
Honda Rebel 500 (2017–Present)
CFMOTO 650NK (2012–Present)

3. V‑Twin (Transverse)

The V‑Twin (Transverse) engine features two cylinders arranged in a V shape, typically set at angles between 45° and 90°, mounted across the frame (perpendicular to the direction of travel). This layout positions the cylinders side to side, exposing them to airflow for cooling and giving the engine a distinctive appearance and sound.

Transverse V‑Twins are most famously associated with American cruiser motorcycles, where the engine layout has become an iconic visual and performance feature. This configuration delivers strong low-end torque, ideal for relaxed highway cruising and laid-back riding styles. However, the transverse mounting can cause uneven cooling in air-cooled models, as the rear cylinder may receive less airflow.

The layout is compact side-to-side but taller vertically, allowing for a lower center of gravity compared to inline-fours. The firing interval and crankpin configuration often result in a unique, throaty exhaust note that many riders find appealing.

Key characteristics of transverse V‑Twin engines:

Two cylinders in a V shape (usually 45–90 degrees)
Mounted across the frame (transversely)
Strong low-end torque
Distinctive sound and character
Common in cruisers and American-style bikes

Historic and popular motorcycles with transverse V‑Twin engines:

Harley-Davidson Knucklehead 61 ci (1936–1947)
Indian Chief 1200 (1922–1953, revived in 1999–Present)
Ducati Monster 696 (2008–2014)
Honda Shadow 750 (1983–2020)
Yamaha Virago XV750 (1981–1997)
Kawasaki Vulcan 800 Classic (1995–2005)
Suzuki Intruder VS800 (1985–2009)
Victory Vegas 8‑Ball (2005–2017)
Indian Scout Bobber (2018–Present)
Harley-Davidson Sportster 1200 (1988–2020)

4. Longitudinal V‑Twin

A longitudinal V‑Twin engine also features two cylinders in a V configuration, but unlike the transverse layout, the cylinders are aligned front-to-back with the crankshaft running in line with the motorcycle frame. This means the cylinder heads point toward the front and rear wheels instead of sticking out sideways.

This layout is often used in motorcycles with shaft drive systems, as it aligns naturally with the drive shaft’s rotational direction. It helps reduce mechanical losses and simplifies power transmission to the rear wheel. However, due to the cylinder layout, it can result in less effective cooling for the rear cylinder in air-cooled setups.

Longitudinal V‑Twins are most famously used by brands like Moto Guzzi and certain older Honda models. These engines are known for their unique side-to-side rocking motion when throttled due to torque reaction, which adds a characteristic feel many riders enjoy.

Key characteristics of longitudinal V‑Twin engines:

V-Twin layout aligned with the frame
Optimized for shaft drive motorcycles
Compact and torquey with good balance
Produces unique torque-induced rocking motion
Efficient drivetrain power transfer

Historic and popular motorcycles with longitudinal V‑Twin engines:

Moto Guzzi V7 Sport (1971–1974)
Moto Guzzi California 1100 (1994–2001)
Moto Guzzi V85 TT (2019–Present)
Moto Guzzi Le Mans 850 (1976–1988)
Honda CX500 (1978–1983)
Honda GL500 Silver Wing (1981–1982)
Ural Retro 750 (2003–Present)
Moto Guzzi Eldorado 1400 (2015–2018)
Royal Enfield KX Concept (prototype, 2019)

5. Boxer Twin (Flat Twin)

The Boxer Twin, also known as the Flat Twin, features two cylinders that lie flat on opposite sides of the engine and move in and out simultaneously like a boxer's fists — hence the name. This layout offers excellent mechanical balance and a low center of gravity, improving handling and ride stability.

Boxer engines are air- or liquid-cooled and are known for their smooth operation and unique horizontal configuration. The design allows both cylinders to be fully exposed to airflow, which helps with cooling, especially in air-cooled engines. The symmetrical layout also reduces engine vibrations, providing a comfortable riding experience.

This engine type is most famously used by BMW, beginning in the 1920s and continuing to this day in their R-series touring and adventure motorcycles. The design has also appeared in other manufacturers' lineups, though it remains most closely associated with BMW Motorrad.

Key characteristics of Boxer Twin engines:

Horizontally opposed two-cylinder layout
Very low center of gravity
Smooth and balanced engine operation
Excellent cooling performance (especially in air-cooled versions)
Wider engine profile across the frame

Historic and popular motorcycles with Boxer Twin engines:

BMW R32 (1923–1926)
BMW R75 (World War II military motorcycle)
BMW R90S (1973–1976)
BMW R100RS (1976–1984)
BMW R1150GS (1999–2004)
BMW R1200RT (2005–2013)
BMW R nineT (2014–Present)
BMW R1250GS (2018–Present)
Ural Gear Up 750 (Russian adventure motorcycle)
Chang Jiang 750 (Chinese military variant based on BMW design)

6. Inline‑Triple (Three‑Cylinder)

The inline-triple engine — or three-cylinder engine — features three cylinders mounted side-by-side in a single bank. This design delivers a perfect blend of torque-rich performance, smooth power delivery, and a distinct exhaust note, making it one of the most exciting and versatile motorcycle engine configurations.

Inline-triples offer better low-end torque than inline-fours while revving higher than most twins. They provide excellent balance between size, weight, and performance, making them ideal for both sporty and touring motorcycles. The engine produces a unique growl that’s popular among enthusiasts, often described as deeper than a four and smoother than a twin.

Though less common than twins or fours, the inline-triple has been used successfully by brands like Triumph, Yamaha, and MV Agusta. Triumph, in particular, is renowned for championing this layout since the 1960s and continues to use it in many of their modern bikes.

Key characteristics of inline-triple engines:

Three cylinders in a single row
Balanced power, torque, and compact size
Unique, raspy exhaust sound
Smoother than a twin, more torque than a four
Great for sporty, naked, and touring motorcycles

Historic and popular motorcycles with inline-triple engines:

Triumph Trident T150 (1968–1975)
Kawasaki H1 Mach III 500 Triple (1969–1975)
Yamaha XS750 (1976–1979)
Triumph Speed Triple 955i (1999–2004)
Triumph Street Triple 675 / 765 (2007–Present)
MV Agusta Brutale 800 (2012–Present)
Triumph Tiger 900 (2020–Present)
Yamaha MT‑09 / FZ‑09 (2014–Present)
Triumph Rocket 3 (2458cc triple – 2019–Present)

7. Inline‑Four

The inline-four engine features four cylinders arranged in a straight line, mounted across the motorcycle frame. Known for its high-revving capability, silky smooth operation, and explosive top-end power, this layout became a benchmark in modern motorcycling — especially in sport and superbikes.

Inline-fours are extremely refined, offering linear power delivery and low vibration. They tend to be wider than other engine types but make up for it with top-tier performance, smoothness, and durability. Most inline-four engines use liquid cooling and multi-valve heads, contributing to higher RPMs and horsepower.

The layout rose to global dominance after Honda introduced the revolutionary CB750 in 1969 — the world’s first “superbike.” Since then, inline-fours have powered some of the fastest, most advanced motorcycles on the road and racetrack.

Key characteristics of inline-four engines:

Four cylinders in a single straight line
Exceptionally smooth and high-revving
Top-end power and sporty character
Wider engine width across the frame
Common in sportbikes, naked bikes, and sport touring

Historic and popular motorcycles with inline-four engines:

Honda CB750 Four (1969–1978)
Kawasaki Z1 900 (1972–1976)
Yamaha FJ1100 / FJ1200 (1984–1996)
Suzuki GSX-R750 (1985–Present)
Honda CBR600RR (2003–Present)
Kawasaki Ninja ZX-10R (2004–Present)
Yamaha YZF-R1 (1998–Present)
BMW S1000RR (2009–Present)
Suzuki Hayabusa GSX1300R (1999–Present)
Honda CB650R (2019–Present)

8. V4 Engine

The V4 engine consists of four cylinders arranged in two banks of two, forming a "V" shape. It combines the compactness of a V‑twin with the performance of an inline‑four, making it a top-tier engine layout used in high-end sport, touring, and racing motorcycles.

V4 engines are known for their incredibly smooth power delivery, strong midrange torque, and thrilling exhaust note. Because of their symmetrical firing order and inherent balance, they produce very little vibration, making them ideal for long-distance rides or aggressive performance use. The layout also allows for mass centralization, which improves handling in performance machines.

While the V4 is more complex and expensive to manufacture, it’s often reserved for premium motorcycles that prioritize performance, refinement, and engineering excellence. It's been used in both legendary race bikes and advanced road bikes from manufacturers like Honda, Ducati, Aprilia, and Yamaha.

Key characteristics of V4 engines:

Four cylinders in a compact V-shaped layout
Smooth, balanced, and powerful across the rev range
Often mounted longitudinally in premium bikes
Rich, unique engine sound
Expensive to build and maintain

Historic and popular motorcycles with V4 engines:

Honda VF750F Interceptor (1983–1985)
Yamaha V-Max 1200 (1985–2007)
Honda VFR750F / VFR800 (1986–2013)
Honda RC30 VFR750R (1987–1990)
Aprilia RSV4 (2009–Present)
Ducati Panigale V4 / V4 S (2018–Present)
Honda RC213V-S (2015–2016)
Yamaha FZR750R OW01 (1989–1991)
Honda Magna V65 (1983–1986)
Aprilia Tuono V4 1100 (2015–Present)

9. L‑Twin (90° V‑Twin)

The L‑Twin engine is a special type of 90-degree V‑Twin layout where one cylinder is mounted horizontally and the other vertically, forming an “L” shape when viewed from the side. This configuration is most famously associated with Ducati, which has used it as a trademark design across their lineup.

L‑Twin engines offer excellent primary balance and smooth power delivery. The wide 90-degree angle helps minimize vibrations, while the layout allows for a compact frame and centralized weight — key advantages in both racing and street riding. Ducati pairs this layout with Desmodromic valve systems, which use cams instead of springs to close valves, allowing for precise and high‑revving performance.

While it shares similarities with traditional V‑Twins, the L‑Twin is typically mounted longitudinally with the front cylinder nearly horizontal. This unique setup also contributes to its iconic deep exhaust note and visual design, easily identifiable in most Ducati models.

Key characteristics of L‑Twin engines:

90-degree V‑Twin layout in an “L” configuration
Excellent torque and smooth balance
Compact, performance-focused design
Deep, throaty exhaust sound
Typically paired with Desmodromic valve systems

Historic and popular motorcycles with L‑Twin engines:

Ducati Pantah 500SL (1980–1983)
Ducati 900SS (1991–1998)
Ducati Monster 696 / 796 / 821 (2008–2020)
Ducati Hypermotard 1100 (2007–2012)
Ducati 1198 Superbike (2009–2011)
Ducati Multistrada 1200 (2010–2017)
Ducati Scrambler Icon 800 (2015–Present)
Ducati ST4S (2001–2006)
Terra Modena 198 Supermoto (Limited 2005)
Cagiva Elefant 900ie (1993–1997)

10. Flat‑Four (Boxer Four)

The Flat‑Four engine, also known as the Boxer Four, features four horizontally opposed cylinders—two on each side of the crankshaft. This layout offers an exceptionally low center of gravity and outstanding engine balance, resulting in a smooth, stable, and comfortable ride—ideal for long-distance touring motorcycles.

By positioning the pistons opposite each other, the flat-four design cancels out vibrations naturally and provides a uniquely stable engine character. It also helps centralize mass and lowers the bike’s center of gravity, contributing to a planted, confidence-inspiring feel, especially at highway speeds.

Flat‑Fours are most famously used in Honda’s Gold Wing models and a few other large-displacement touring motorcycles. These engines are built for smooth power delivery and quiet performance, making them favorites among touring riders who prioritize comfort, reliability, and refinement.

Key characteristics of Flat‑Four engines:

Four horizontally opposed cylinders
Extremely smooth and well-balanced
Low center of gravity for enhanced stability
Ideal for touring motorcycles
Known for quiet operation and longevity

Historic and popular motorcycles with Flat‑Four engines:

Honda GL1000 Gold Wing (1975–1979)
Honda GL1100 Gold Wing (1980–1983)
Honda GL1200 Gold Wing (1984–1987)
Honda Valkyrie 1500 (1996–2003)
Moto Guzzi V1000 Convert Prototype (1975, concept)
Honda CBX Flat-Six (related inline inspiration, 1978–1982)
Custom Café Racer Gold Wing Builds (GL1000/GL1100 variants)

11. Inline‑Six

The inline-six engine features six cylinders arranged in a single straight row, mounted transversely across the motorcycle frame. It is one of the smoothest-running engine configurations ever created due to its perfect primary and secondary balance. These engines deliver exceptional top-end power and a turbine-like riding experience.

Inline-six engines are mechanically complex, wide, and often heavier than other configurations, which limits their use to select high-performance and touring motorcycles. However, the reward is ultra-smooth operation, linear power delivery, and a signature wailing exhaust sound that stands out among all engine types.

This layout was famously introduced in production motorcycles by Honda with the CBX1000 in the late 1970s. Today, BMW continues the legacy with its K1600 series. Inline-sixes remain highly respected for their refinement and are often found in flagship machines built for luxury or speed.

Key characteristics of Inline‑Six engines:

Six cylinders in a single straight row
Exceptionally smooth and balanced
High power output and linear delivery
Wide engine profile (side-to-side)
Used in top-tier performance or touring bikes

Historic and popular motorcycles with Inline‑Six engines:

Honda CBX1000 (1978–1982)
Kawasaki KZ1300 (1979–1989)
Benelli Sei 750 / 900 (1973–1989)
BMW K1600GT / K1600GTL (2011–Present)
Horex VR6 Roadster (2012–2019, narrow-angle 6-cylinder)
Custom-built inline-six Café Racers (CBX-based)
Benelli 504 Sport (related to 6-cylinder legacy)

12. Flat‑Six (Boxer Six)

The flat-six engine, also known as the boxer-six, features six horizontally opposed cylinders — three on each side of the crankshaft. This configuration offers a perfect mechanical balance, leading to incredibly smooth and quiet engine operation. It provides excellent mass centralization and a low center of gravity, which enhances stability and comfort over long distances.

Flat-six engines are wide, but their low profile allows them to sit low in the frame, helping balance and handling on large motorcycles. These engines are typically liquid-cooled and tuned for low-end torque and smooth acceleration, making them ideal for touring applications.

The most famous use of the flat-six in motorcycling is the Honda Gold Wing, which evolved from a flat-four to a flat-six in the late 1980s. The layout has also appeared in rare custom or limited-production bikes due to its complexity and cost, but it remains the gold standard in luxury motorcycle touring.

Key characteristics of Flat‑Six engines:

Six horizontally opposed cylinders (boxer layout)
Extremely smooth and vibration-free
Low center of gravity improves stability
Broad, flat power delivery — perfect for touring
Most common in high-end luxury motorcycles

Historic and popular motorcycles with Flat‑Six engines:

Honda Gold Wing GL1500 (1988–2000)
Honda Gold Wing GL1800 (2001–2017)
Honda Gold Wing GL1800 DCT / Tour (2018–Present)
Honda Valkyrie Rune (2004–2005)
Honda F6B (2013–2017)
Custom Gold Wing baggers and touring builds
Rare sidecar builds based on Gold Wing platforms

13. Square Four

The Square Four engine is a unique four-cylinder configuration created by combining two parallel-twin engines—mounted one behind the other—with two crankshafts geared together. It forms a “square” shape when viewed from above, hence the name. This layout was developed to deliver the power of four cylinders in a compact form.

The Square Four was notably designed by Edward Turner in the early 1930s and became famous through its use in the Ariel motorcycles. It offered more power and refinement than traditional twins of the time while retaining a narrow profile. However, it was mechanically complex, heavy, and ran hot, especially in the rear cylinders.

Although the engine layout saw limited use, the bikes that featured it became collector icons due to their innovation, sound, and British engineering heritage. Today, Square Four engines are rare and admired for their mechanical uniqueness and historical importance.

Key characteristics of Square Four engines:

Four cylinders arranged in a square pattern
Two crankshafts geared together
Narrow design for a four-cylinder engine
High torque with smooth power delivery
Complex and heavy compared to inline-fours

Historic motorcycles with Square Four engines:

Ariel Square Four 500cc (1931–1936)
Ariel Square Four 600cc OHV (1936–1948)
Ariel Square Four Mark I 997cc (1949–1953)
Ariel Square Four Mark II 997cc (1953–1959)
Custom-built Square Four café racers (rare collector builds)

14. Rotary (Wankel)

The rotary engine, also known as the Wankel engine, is a completely different internal combustion engine design that uses a rotating triangular rotor instead of traditional pistons. It operates on the same four-stroke cycle—intake, compression, power, and exhaust—but completes it using an eccentric rotating motion within an oval-like chamber.

This design allows the rotary engine to be extremely compact and lightweight compared to piston engines with similar power output. It revs freely, runs smoothly, and produces a unique, high-pitched sound. However, rotary engines tend to run hot, consume more fuel and oil, and are harder to seal, which has limited their widespread use in motorcycles.

Despite its drawbacks, the rotary engine captured attention for its innovation and was used by a few bold manufacturers. Most notably, Suzuki released the RE5 in the 1970s, and Norton created rotary-powered race bikes and limited production models. These motorcycles remain cult classics and rare collector’s items.

Key characteristics of Rotary (Wankel) engines:

No pistons — uses a spinning rotor
Compact and lightweight design
High-revving with a unique engine sound
Low vibration and smooth power delivery
Higher fuel and oil consumption

Historic and rare motorcycles with Rotary (Wankel) engines:

Suzuki RE5 (1974–1976)
Hercules W-2000 (1974–1977)
Norton Interpol 2 (1984–1992 – Police use)
Norton F1 Sport / F1 Classic (1990–1996)
Van Veen OCR 1000 (1978 – Limited Dutch production)
DKW Wankel Prototype (1960s – Experimental)
Custom rotary cafe racers based on Mazda engines (rare builds)

15. Tandem Twin

The Tandem Twin engine features two cylinders aligned one behind the other (front-to-back) along a single crankshaft axis. This compact design allows the engine to remain narrow while delivering the power of a twin-cylinder setup, making it ideal for racing motorcycles where frontal aerodynamics and central weight distribution are critical.

Unlike parallel twins, which place both cylinders side-by-side, the tandem layout stacks them longitudinally, saving width and allowing a shorter, more streamlined frame. This configuration was primarily used in high-performance two-stroke Grand Prix motorcycles during the 1970s and 1980s, where lightweight and explosive power were essential.

Although rare in production motorcycles due to its complexity and limited street practicality, the tandem twin is a fascinating example of engineering creativity focused on competition performance.

Key characteristics of Tandem Twin engines:

Two cylinders aligned front-to-back on one crankshaft
Extremely narrow and compact layout
Primarily used in two-stroke race bikes
Explosive power and lightweight construction
Rare in road-legal motorcycles

Historic motorcycles with Tandem Twin engines:

Kawasaki KR250 (1984–1990)
Kawasaki KR350 GP bike (1978–1982)
Yamaha TZ250 (early 1980s versions)
Custom two-stroke tandem twin race builds (track only)
Experimental Bimota and Italian GP two-strokes (limited use)

16. Opposed Twin

The Opposed Twin engine is a type of flat twin design where two cylinders face away from each other in a horizontal, 180-degree layout. Each piston moves in opposition to the other, providing excellent engine balance and reducing vibration. This configuration is particularly known for its smoothness, cooling efficiency, and mechanical durability.

While the term "Boxer Twin" is often used today (especially by BMW), "Opposed Twin" was a common description in earlier decades and among other manufacturers. It has been used in motorcycles, aircraft, and military vehicles, where reliability and simplicity were essential.

Opposed twin engines gained fame through BMW’s pre-war and post-war motorcycles, including models used during World War II. The layout’s low center of gravity and direct shaft-drive compatibility made it ideal for both road touring and rugged terrain.

Key characteristics of Opposed Twin engines:

Two cylinders mounted horizontally opposite each other
Smooth, balanced performance with low vibration
Great cooling from exposed cylinder heads
Common in vintage and military applications
Ideal for shaft-driven motorcycles

Historic and popular motorcycles with Opposed Twin engines:

BMW R12 (1935–1942 – WWII German military use)
BMW R75 (1941–1944 – with sidecar)
BMW R50 / R60 series (1950s–1960s)
Steib Sidecar + BMW R69S (1955–1969)
Ural M72 (1950s Soviet copy of BMW design)
Chang Jiang CJ750 (Chinese clone of the BMW R71)
Zündapp KS750 (German flat twin – WWII)

17. T‑Plane Crank Triple

The T‑Plane Crank Triple is a modern variation of the inline-three-cylinder engine featuring a staggered (T-plane) crankshaft. This setup spaces the crank pins unevenly to deliver irregular firing intervals — creating traction-friendly torque pulses more akin to a twin, while still retaining the mid-range power and character of a triple.

Traditional inline-triples use a 120° crankshaft for smooth and even firing. In contrast, the T‑Plane setup (usually 180°–90°–270°) gives the engine a more rugged feel, better traction under low grip conditions, and a distinctive exhaust note. This layout is engineered to mimic the advantages of a twin-cylinder off-road bike with the added performance of a triple.

Triumph popularized the T‑Plane crank with their Tiger 900 and 1200 series, targeting riders who want adventure-bike performance, tractable power, and characterful engine response. The result is an engine with more “bite,” ideal for both road and trail use.

Key characteristics of T‑Plane Crank Triple engines:

Three-cylinder engine with uneven firing intervals
Increased traction and throttle control at low speeds
Blend of twin-like feel and triple performance
Unique exhaust note and engine feedback
Focused on off-road and adventure applications

Modern motorcycles with T‑Plane Crank Triple engines:

Triumph Tiger 900 GT / Rally / Pro (2020–Present)
Triumph Tiger 1200 Explorer / GT / Rally (2022–Present)
Prototype triple-crankshaft designs (exclusive to Triumph currently)

18. Big‑Bang Inline‑Four

The Big‑Bang Inline‑Four engine is a variant of the traditional inline-four layout that uses uneven firing intervals to mimic the torque delivery characteristics of a V‑Twin or T‑Plane triple. Instead of evenly spaced combustion pulses (e.g., 180° apart), the Big‑Bang setup fires multiple cylinders closer together, followed by a longer gap — like a “bang-bang-rest” rhythm.

This configuration enhances rear wheel traction and throttle control, especially during corner exits, by allowing the tire a brief moment to recover between power pulses. Originally developed for MotoGP racing, the Big‑Bang concept has made its way into select high-performance road bikes to provide better ride feel and usable torque delivery.

While traditional inline-fours are known for high revs and peak power, Big‑Bang variants trade a bit of that top-end speed for better mid-range drive and traction. It offers the benefits of modern engine management with a more connected and confidence-inspiring feel.

Key characteristics of Big‑Bang Inline‑Four engines:

Four-cylinder engine with uneven firing intervals
Improved traction and smoother power delivery
Better corner exit control, especially in racing
Heavily used in MotoGP and advanced sportbikes
Produces a unique, deeper exhaust tone

Motorcycles using Big‑Bang Inline‑Four or derived technology:

Yamaha YZR-M1 MotoGP bike (2002–Present)
Yamaha YZF-R1 Crossplane Crank (2009–Present)
Honda RC213V MotoGP bike (2003–Present)
Aprilia RS-GP (MotoGP variant with firing order tweaks)
Yamaha R1M / R1 GYTR (Track-focused editions)

19. Reverse Inline‑Four

The Reverse Inline‑Four engine is a modern evolution of the traditional inline‑four, where the cylinders are tilted backward instead of forward. This layout shifts the engine’s mass toward the center of the motorcycle, improving balance, agility, and weight distribution — especially under hard braking and aggressive cornering.

Originally used in MotoGP prototypes, the reverse inline‑four made its way into production motorcycles with Yamaha’s YZF‑R1 in 2015. By slanting the engine rearward and moving the air intake toward the front, this layout allows for a shorter and more efficient intake path, better aerodynamics, and a more compact chassis design.

Though not mechanically different in terms of cylinder firing or count, this engine configuration represents a major step in handling optimization for high-speed track riding. It’s primarily used in high-end sportbikes where weight centralization is critical.

Key characteristics of Reverse Inline‑Four engines:

Four cylinders tilted backward toward the rider
Mass centralized for improved handling
Front-mounted air intake for better airflow
More compact and aerodynamic chassis design
Developed from MotoGP technology

Motorcycles featuring Reverse Inline‑Four engines:

Yamaha YZF-R1 (2015–Present)
Yamaha YZF-R1M (Track-focused, 2015–Present)
Yamaha M1 (MotoGP platform inspiration)
Yamaha YZF-R6 GYTR (race builds, adapted concepts)
Concept superbikes from Yamaha R&D

20. Electric Motor (Brushless)

The brushless electric motor is a revolutionary step in motorcycle propulsion, replacing internal combustion engines with magnetically driven, zero-emission power. These motors use no pistons or crankshafts and instead rely on electromagnetic fields to generate rotational force. The result is instant torque, near-silent operation, and incredibly smooth acceleration.

Brushless motors are highly efficient, compact, and require minimal maintenance. With no oil changes, fuel systems, or exhausts, they’re environmentally friendly and ideal for city commuting, off-road exploration, and even racing. Many electric motorcycles use regenerative braking to recharge the battery while riding.

The performance spectrum has rapidly grown, from light commuter EVs to powerful machines that rival 1000cc superbikes. Although battery range and charging infrastructure are still developing, electric motorcycles continue to gain popularity as both a practical and thrilling alternative.

Key characteristics of Electric Brushless motors:

Silent and vibration-free operation
Instant torque with no lag
No oil, fuel, clutch, or gear shifting
Low maintenance and high efficiency
Zero tailpipe emissions

Popular motorcycles with Electric Brushless motors:

Zero SR/F (2019–Present)
Harley-Davidson LiveWire / LiveWire ONE (2019–Present)
Energica Ego / Eva Ribelle (2015–Present)
KTM Freeride E-XC (off-road electric)
CAKE Kalk OR / INK (2020–Present)
NIU MQi GT EVO (urban smart scooter)
Damon Hypersport (prototype, 2023+)
Arc Vector (high-performance electric, UK-based)
Sur-Ron Light Bee X (lightweight e-moto)
BMW CE 04 (electric urban scooter)

21. Gas Turbine

A gas turbine engine operates similarly to a jet engine. It compresses air, mixes it with fuel, and ignites the mixture to produce high-velocity exhaust gases that spin turbine blades — generating power. In motorcycles, this creates an extremely powerful and exotic propulsion system, rarely seen outside of prototypes or special builds.

Gas turbines offer incredible power-to-weight ratios and can produce immense horsepower in a relatively compact form. However, they come with trade-offs: high operating temperatures, poor fuel economy, slow throttle response, and intense noise. These engines are more at home in aircraft or tanks — but a few daring innovators have put them on two wheels.

The most famous gas turbine motorcycle is the MTT Y2K — a street-legal superbike powered by a Rolls-Royce jet engine. Only a handful of gas turbine motorcycles exist, but their performance and sound are nothing short of jaw-dropping.

Key characteristics of Gas Turbine engines:

Jet engine-style power system
Unmatched power-to-weight ratio
Extremely high exhaust temperatures
Distinctive jet-like sound
Rare and mostly experimental

Historic and notable motorcycles with Gas Turbine engines:

MTT Y2K Turbine Superbike (2000–Present)
MTT 420RR (427 hp upgrade of the Y2K, 2017–Present)
Turbinator 2 (land speed record streamliner)
Rover Jet Bike (experimental UK concept, 1950s)
Whitelock Tinker Toy (Rolls-Royce Allison engine custom build)
Custom jet-powered drag bikes (limited and handmade)

22. Diesel Engine

A diesel engine operates through compression ignition — compressing air until it's hot enough to ignite fuel without a spark plug. Known for their durability and high torque at low RPMs, diesel engines are common in trucks and heavy-duty vehicles, but rarely used in motorcycles due to weight, vibration, and slower revving nature.

In motorcycles, diesel engines offer excellent fuel economy and range, making them ideal for long-distance or utility-focused applications. They're also better suited for harsh environments due to their robust design and lower flammability risk. Military forces have experimented with diesel motorcycles for logistical advantages and the ability to use a common battlefield fuel.

Though not mainstream, diesel motorcycles have a niche following, and several companies have produced limited models or custom conversions. Some adventure riders have also built their own diesel machines for remote overland travel.

Key characteristics of Diesel motorcycle engines:

High torque at low RPMs
Superior fuel efficiency and long range
Built for durability and longevity
Heavier and slower revving than petrol engines
Rare in consumer motorcycle markets

Motorcycles with Diesel engines (production or experimental):

Royal Enfield Taurus Diesel (1980s–2000s – India only)
Hayes M1030M1 (Kawasaki KLR650 diesel conversion for U.S. military)
Sommer Diesel 462 (Germany – based on Enfield design)
Track T800 CDI (2009–2012 – Dutch-built adventure diesel)
Neander Turbo Diesel (Germany – prototype cruiser)
Custom diesel Enfield conversions (enthusiast builds)
Kawasaki KLR D650 (military diesel test mule)

23. Radial Engine

A radial engine features multiple cylinders arranged in a circle around a central crankshaft, much like engines used in old-school propeller airplanes. Each cylinder fires in sequence to spin the crankshaft, resulting in a unique torque delivery and an unmistakable sound. In motorcycles, this layout is incredibly rare and mostly used for custom builds or engineering showcases.

The radial engine is mechanically complex and physically large, making it impractical for mass-produced motorcycles. However, a few wild and fully functional radial-engine motorcycles have been built over the years, typically by hand and as passion projects. Their appeal lies in their sheer mechanical presence, historical aviation roots, and visual spectacle.

Despite their impracticality for everyday riding, radial motorcycles have gained legendary status in the custom bike world — often featured at major shows or museums. Their rumbling, low-RPM operation and steampunk aesthetic make them unforgettable.

Key characteristics of Radial engines in motorcycles:

Multiple cylinders arranged in a circle
Originally designed for airplanes
Heavy, wide, and mechanically complex
Rare and mostly custom-built
Incredible visual and audible presence

Notable motorcycles with Radial engines:

Megola Touring Motorcycle (Germany, 1921–1925 – 5-cylinder radial front wheel)
Redrup Radial Motorcycle (UK, 1919 – experimental 3-cylinder radial)
Rotec Radial Motorcycle (Australia, 7-cylinder aircraft engine custom build)
JRL Cycles Lucky 7 (U.S., 2007 – 7-cylinder radial V-twin hybrid)
Ironhead Engineering custom radial projects (show builds)
Radial-powered choppers (various private builds)

24. Hybrid Engine (ICE + Electric)

A hybrid motorcycle engine combines a traditional internal combustion engine (ICE) with an electric motor. The two power sources work together to improve fuel efficiency, reduce emissions, and enhance performance. Depending on the design, hybrid systems can run on electric-only power at low speeds and switch to gasoline at higher speeds — or use both for performance bursts.

This configuration allows motorcycles to benefit from the instant torque of electric motors while retaining the longer range and refueling ease of gasoline engines. Hybrids also support regenerative braking, capturing energy during deceleration and feeding it back into the battery system.

Although hybrid motorcycles are still rare in the commercial market, several manufacturers are exploring or prototyping them. The goal is to reduce environmental impact without compromising on the thrill and range expected from motorcycles.

Key characteristics of Hybrid motorcycle engines:

Combination of petrol (ICE) and electric motors
Lower emissions and improved fuel economy
Electric-only mode available at low speeds
Enhanced performance via dual power sources
Still under development in mainstream motorcycle markets

Examples and prototypes of Hybrid motorcycles:

Piaggio MP3 Hybrid (2009–2014 – hybrid scooter)
Yamaha Gen-Ryu Concept (2005 – hybrid sport-touring prototype)
Honda PCX Hybrid Scooter (Japan/Asia – 2018–2021)
Kymco Ionex Hybrid Concepts (2022+)
Kawasaki Hybrid Electric Motorcycle Prototype (announced 2022)
Rokon Trail-Breaker (hybrid-style auxiliary power system)
Custom EV + ICE conversions by builders and universities

25. Steam Engine

The steam engine is one of the earliest types of powerplants used in motorcycle development. Unlike modern engines that burn fuel inside a cylinder, a steam engine uses heated water to create pressurized steam, which drives a piston or rotary mechanism. These engines were bulky, complex, and slow to start — but they laid the groundwork for motorized transport.

Steam-powered motorcycles appeared in the late 1800s, well before internal combustion engines became practical. They were experimental and rare, often handcrafted by inventors pushing the limits of technology at the time. While not efficient or convenient by today’s standards, steam motorcycles were instrumental in proving the concept of powered personal transport.

Today, steam-powered motorcycles are historic artifacts and museum pieces, with a few functioning replicas built by enthusiasts to preserve early engineering ingenuity.

Key characteristics of Steam engines in motorcycles:

Powered by pressurized steam from boiling water
Low-speed operation with long startup time
Bulky design and heavy chassis
Fascinating mechanical movement and sound
Rare, historic, and manually intensive to operate

Historic steam-powered motorcycles:

Roper Steam Velocipede (USA, 1867–1869 – one of the first motorcycles ever built)
Michaux-Perreaux Steam Bicycle (France, 1868 – earliest known steam two-wheeler)
Daimler Petroleum Reitwagen (1885 – often cited as a successor to steam designs)
Sylvester Roper Steam Motorcycle (later models, 1894 exhibition)
Modern steam bike replicas (museum or enthusiast-built)

Special thanks to the Naked Racer Moto Co team for support in collecting information.

Chris Wells

July 29, 2025

Motorcycle Restore Motorcycle Review

Chris WellsAuthor posts

Chris Wells is a Workshop Manager at Naked Racer Workshop, with over 35 years of experience as a motorcycle mechanic. For the past 10 years, he has been a key figure at Naked Racer, specializing in custom motorcycle builds, engine tuning, and fabrication. His expertise spans vintage restorations, performance upgrades, and frame modifications, making him a go-to professional in the world of custom motorcycles.

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