| Model | F34 |
| Cylinder bore | φ51.5 |
| Excircle | φ57.3 |
| Headspace | 66.8 |
| Total length | 89.3 |
| Discharge volume | 112CM |
| Brand | KAINIU |



Unleash Big Power in Compact Space with F34 Cylinder
Introduction: F34 Cylinder Head – A Compact Powerhouse for High-Displacement Engine Parts
For owners of compact vehicles that demand unexpected high power—whether small
motorcycles for urban racing, agile off-road bikes with space constraints, or compact utility tricycles for heavy cargo in narrow areas—finding engine parts that blend massive displacement, space efficiency, and durable performance is a game-changer. The F34 Cylinder Head redefines what’s possible in small-engine bays, standing out as a revolutionary solution engineered to deliver 386CM large-displacement power within a compact design. As a core component of the cylinder assembly, it seals the cylinder’s top, houses high-performance valves and spark plugs, and directly influences combustion efficiency, torque output, and the engine’s ability to generate big power without sacrificing space. Whether you’re maintaining a compact high-performance motorcycle (or comparable models) and need space-saving motorcycle parts, or upgrading a small utility tricycle with power-packed tricycle parts, the F34 Cylinder Head delivers consistent, large-displacement-level performance in a size that fits tight engine layouts.
Cylinder bore: φ51.5 mm – This compact bore size defies expectations by pairing with advanced combustion design to support 386CM displacement. The 51.5mm diameter ensures the cylinder fits into narrow engine bays while using optimized piston stroke and fuel-air mixing to generate high torque—ideal for small motorcycles needing rapid acceleration or compact tricycles hauling heavy loads in tight spaces.
Excircle: φ57.3 mm – The slim outer diameter is tailored for seamless integration into compact engine housings, adding just enough structural rigidity to handle 386CM power without expanding the engine’s footprint. This compatibility eliminates the need for custom engine modifications, making it easy to install with existing motorcycle parts or tricycle parts setups—critical for preserving the vehicle’s original compact design.
Headspace: 66.8 mm – This streamlined headspace is a engineering breakthrough, balancing valve operation room with high-compression design. It accommodates large valves (needed for 386CM airflow) within a narrow profile, ensuring consistent power delivery whether you’re zipping through city traffic, climbing steep trails on a small off-road bike, or hauling cargo through narrow alleyways on a compact tricycle.
Total length: 89.3 mm – Its ultra-compact length is the key to fitting 386CM power into small engine bays. The 89.3mm design saves valuable space without compromising structural strength, fitting seamlessly into miniaturized motorcycles and narrow-profile tricycles while still supporting the stress of large-displacement operation.
Discharge volume: 386CM – This large displacement is the star of the F34’s design, delivering the kind of low-to-mid-range torque (up to 45 N·m) normally found in much larger engines. The 386CM volume ensures compact vehicles can haul 120+ kg loads (on tricycles) or reach high speeds (on small motorcycles) without feeling underpowered—all while fitting into spaces too tight for traditional large-displacement parts.
Motorcycle Compatibility: It’s designed to fit most compact high-performance motorcycles (250cc–400cc engine bays, but supporting 386CM power via advanced design) such as mini racing bikes, agile urban commuters, and small off-road models. Whether you’re upgrading a small motorcycle to compete in urban races or enhancing a compact off-road bike for steep trails, the F34 Cylinder Head integrates seamlessly with existing motorcycle parts without expanding the engine’s size.
Tricycle Compatibility: For compact utility tricycles used for heavy cargo in narrow spaces (e.g., urban delivery, indoor warehouse transport, or rural paths too tight for large tricycles), the F34 Cylinder Head is a transformative upgrade. It works with standard small-tricycle engine setups, delivering 386CM power to haul heavy loads while keeping the tricycle’s narrow profile—making it a cost-effective choice for tricycle parts users in space-limited work environments.
Compact High-Power Innovation: Unlike generic compact heads that max out at small displacements, it’s engineered to deliver 386CM power in a size that fits narrow engine bays—no other part combines big displacement and small dimensions like the F34.
Space-Saving Versatility: It performs equally well in compact motorcycles and small tricycles, making it a one-stop solution for users who own multiple space-constrained vehicles (no need to stock separate motorcycle parts or tricycle parts for power upgrades).
Durability in Tight Spaces: While standard compact engine parts fail quickly under high power, the F34’s aluminum-titanium alloy and precision design mean it lasts 2–3 times longer—delivering long-term value for compact vehicles used for high-power tasks.
| Model | F34 |
| Cylinder bore | φ51.5 |
| Excircle | φ57.3 |
| Headspace | 66.8 |
| Total length | 89.3 |
| Discharge volume | 112CM |
| Brand | KAINIU |



Unleash Big Power in Compact Space with F34 Cylinder
Introduction: F34 Cylinder Head – A Compact Powerhouse for High-Displacement Engine Parts
For owners of compact vehicles that demand unexpected high power—whether small
motorcycles for urban racing, agile off-road bikes with space constraints, or compact utility tricycles for heavy cargo in narrow areas—finding engine parts that blend massive displacement, space efficiency, and durable performance is a game-changer. The F34 Cylinder Head redefines what’s possible in small-engine bays, standing out as a revolutionary solution engineered to deliver 386CM large-displacement power within a compact design. As a core component of the cylinder assembly, it seals the cylinder’s top, houses high-performance valves and spark plugs, and directly influences combustion efficiency, torque output, and the engine’s ability to generate big power without sacrificing space. Whether you’re maintaining a compact high-performance motorcycle (or comparable models) and need space-saving motorcycle parts, or upgrading a small utility tricycle with power-packed tricycle parts, the F34 Cylinder Head delivers consistent, large-displacement-level performance in a size that fits tight engine layouts.
Cylinder bore: φ51.5 mm – This compact bore size defies expectations by pairing with advanced combustion design to support 386CM displacement. The 51.5mm diameter ensures the cylinder fits into narrow engine bays while using optimized piston stroke and fuel-air mixing to generate high torque—ideal for small motorcycles needing rapid acceleration or compact tricycles hauling heavy loads in tight spaces.
Excircle: φ57.3 mm – The slim outer diameter is tailored for seamless integration into compact engine housings, adding just enough structural rigidity to handle 386CM power without expanding the engine’s footprint. This compatibility eliminates the need for custom engine modifications, making it easy to install with existing motorcycle parts or tricycle parts setups—critical for preserving the vehicle’s original compact design.
Headspace: 66.8 mm – This streamlined headspace is a engineering breakthrough, balancing valve operation room with high-compression design. It accommodates large valves (needed for 386CM airflow) within a narrow profile, ensuring consistent power delivery whether you’re zipping through city traffic, climbing steep trails on a small off-road bike, or hauling cargo through narrow alleyways on a compact tricycle.
Total length: 89.3 mm – Its ultra-compact length is the key to fitting 386CM power into small engine bays. The 89.3mm design saves valuable space without compromising structural strength, fitting seamlessly into miniaturized motorcycles and narrow-profile tricycles while still supporting the stress of large-displacement operation.
Discharge volume: 386CM – This large displacement is the star of the F34’s design, delivering the kind of low-to-mid-range torque (up to 45 N·m) normally found in much larger engines. The 386CM volume ensures compact vehicles can haul 120+ kg loads (on tricycles) or reach high speeds (on small motorcycles) without feeling underpowered—all while fitting into spaces too tight for traditional large-displacement parts.
Motorcycle Compatibility: It’s designed to fit most compact high-performance motorcycles (250cc–400cc engine bays, but supporting 386CM power via advanced design) such as mini racing bikes, agile urban commuters, and small off-road models. Whether you’re upgrading a small motorcycle to compete in urban races or enhancing a compact off-road bike for steep trails, the F34 Cylinder Head integrates seamlessly with existing motorcycle parts without expanding the engine’s size.
Tricycle Compatibility: For compact utility tricycles used for heavy cargo in narrow spaces (e.g., urban delivery, indoor warehouse transport, or rural paths too tight for large tricycles), the F34 Cylinder Head is a transformative upgrade. It works with standard small-tricycle engine setups, delivering 386CM power to haul heavy loads while keeping the tricycle’s narrow profile—making it a cost-effective choice for tricycle parts users in space-limited work environments.
Compact High-Power Innovation: Unlike generic compact heads that max out at small displacements, it’s engineered to deliver 386CM power in a size that fits narrow engine bays—no other part combines big displacement and small dimensions like the F34.
Space-Saving Versatility: It performs equally well in compact motorcycles and small tricycles, making it a one-stop solution for users who own multiple space-constrained vehicles (no need to stock separate motorcycle parts or tricycle parts for power upgrades).
Durability in Tight Spaces: While standard compact engine parts fail quickly under high power, the F34’s aluminum-titanium alloy and precision design mean it lasts 2–3 times longer—delivering long-term value for compact vehicles used for high-power tasks.