| Model | F3 |
| Cylinder bore | φ83 |
| Excircle | φ89.1 |
| Headspace | 89.6 |
| Total length | 124.5 |
| Discharge volume | 386CM |
| Brand | KAINIU |



Unleash High-Performance Power with F3 Cylinder Head for Large-Displacement Engines
Cylinder bore: φ83 mm – This large-diameter bore is perfectly matched to 386CM displacement, enabling maximum piston movement and enhanced fuel-air intake volume within the cylinder. The 83mm diameter creates ample combustion space for generating high torque (ideal for hauling heavy cargo or accelerating large motorcycles) while maintaining efficient gas flow to prevent power loss at high RPMs.
Excircle: φ89.1 mm – The outer diameter is designed for a ultra-stable fit with large-displacement engine housings, adding structural rigidity to handle the intense vibrations and pressure of high-output operation. This compatibility eliminates the need for custom modifications, making it easy to integrate with existing motorcycle parts or tricycle parts setups—critical for minimizing downtime in industrial or high-use scenarios.
Headspace: 89.6 mm – This generous headspace is engineered to optimize compression ratio for large-displacement engines, accommodating larger valves and high-flow ports. It provides sufficient room for valve operation while boosting combustion pressure, ensuring consistent power delivery whether you’re cruising at highway speeds, climbing steep grades with a load, or accelerating rapidly on open terrain.
Total length: 124.5 mm – Its extended length is tailored to the larger engine bays of high-displacement vehicles, balancing space for high-performance components (like reinforced valve trains) with structural strength. The design fits seamlessly into heavy-duty motorcycles and industrial tricycles, without compromising handling or load capacity.
Discharge volume: 386CM – This large displacement aligns perfectly with the power needs of heavy-duty vehicles, ensuring the Cylinder Head works in harmony with the engine’s overall design. The 386CM volume delivers exceptional low-to-mid-range torque and high-top-end power—strong enough to haul 150+ kg loads (on tricycles) or power large motorcycles through long-distance tours without performance degradation.
Wide Compatibility – F3 Cylinder Head Fits Diverse Large-Displacement Vehicles
Motorcycle Compatibility: It’s designed to fit most large-displacement motorcycles (500cc–800cc, compatible with 386CM core displacement) such as touring bikes, heavy off-road models, and power cruisers. Whether you’re repairing a motorcycle used for cross-country tours or upgrading an older model to boost performance, the F3 Cylinder Head integrates seamlessly with existing motorcycle parts.
Tricycle Compatibility: For industrial-grade 386CM+ utility tricycles used for heavy cargo transport (e.g., construction materials, agricultural supplies) or commercial delivery (e.g., large-scale logistics), the F3 Cylinder Head is a reliable upgrade. It works with standard large-displacement tricycle engine setups, providing the extra durability and power needed for daily heavy hauling—making it a cost-effective choice for tricycle parts users in industrial sectors.
This compatibility ensures that no matter your large-displacement vehicle type, the F3 Cylinder Head is a plug-and-play solution that works in harmony with your existing engine parts.
Exceptional Torque for Heavy Loads: The φ83 mm cylinder bore and 386CM discharge volume work together to deliver massive low-end torque (up to 50 N·m), making it easy to haul 150–200kg loads (on tricycles) or accelerate large motorcycles from a stop without straining the engine. This torque ensures consistent performance even when the vehicle is under maximum stress.
Thermal Stability for Sustained Use: The copper-infused aluminum alloy and ceramic coating excel at heat dissipation, keeping engine temperatures in check even during sustained high-RPM operation (e.g., long highway stretches or continuous cargo hauling). This prevents overheating-related power dips and extends the lifespan of other engine parts (like pistons and gaskets).
Reduced Maintenance for High-Use Scenarios: The reinforced materials and precision seal minimize wear on critical components, cutting down on unexpected repairs in industrial or high-mileage use. For business owners or enthusiasts who rely on their large-displacement vehicles for daily use, this means more time on the road and less money spent on replacement parts.
| Model | F3 |
| Cylinder bore | φ83 |
| Excircle | φ89.1 |
| Headspace | 89.6 |
| Total length | 124.5 |
| Discharge volume | 386CM |
| Brand | KAINIU |



Unleash High-Performance Power with F3 Cylinder Head for Large-Displacement Engines
Cylinder bore: φ83 mm – This large-diameter bore is perfectly matched to 386CM displacement, enabling maximum piston movement and enhanced fuel-air intake volume within the cylinder. The 83mm diameter creates ample combustion space for generating high torque (ideal for hauling heavy cargo or accelerating large motorcycles) while maintaining efficient gas flow to prevent power loss at high RPMs.
Excircle: φ89.1 mm – The outer diameter is designed for a ultra-stable fit with large-displacement engine housings, adding structural rigidity to handle the intense vibrations and pressure of high-output operation. This compatibility eliminates the need for custom modifications, making it easy to integrate with existing motorcycle parts or tricycle parts setups—critical for minimizing downtime in industrial or high-use scenarios.
Headspace: 89.6 mm – This generous headspace is engineered to optimize compression ratio for large-displacement engines, accommodating larger valves and high-flow ports. It provides sufficient room for valve operation while boosting combustion pressure, ensuring consistent power delivery whether you’re cruising at highway speeds, climbing steep grades with a load, or accelerating rapidly on open terrain.
Total length: 124.5 mm – Its extended length is tailored to the larger engine bays of high-displacement vehicles, balancing space for high-performance components (like reinforced valve trains) with structural strength. The design fits seamlessly into heavy-duty motorcycles and industrial tricycles, without compromising handling or load capacity.
Discharge volume: 386CM – This large displacement aligns perfectly with the power needs of heavy-duty vehicles, ensuring the Cylinder Head works in harmony with the engine’s overall design. The 386CM volume delivers exceptional low-to-mid-range torque and high-top-end power—strong enough to haul 150+ kg loads (on tricycles) or power large motorcycles through long-distance tours without performance degradation.
Wide Compatibility – F3 Cylinder Head Fits Diverse Large-Displacement Vehicles
Motorcycle Compatibility: It’s designed to fit most large-displacement motorcycles (500cc–800cc, compatible with 386CM core displacement) such as touring bikes, heavy off-road models, and power cruisers. Whether you’re repairing a motorcycle used for cross-country tours or upgrading an older model to boost performance, the F3 Cylinder Head integrates seamlessly with existing motorcycle parts.
Tricycle Compatibility: For industrial-grade 386CM+ utility tricycles used for heavy cargo transport (e.g., construction materials, agricultural supplies) or commercial delivery (e.g., large-scale logistics), the F3 Cylinder Head is a reliable upgrade. It works with standard large-displacement tricycle engine setups, providing the extra durability and power needed for daily heavy hauling—making it a cost-effective choice for tricycle parts users in industrial sectors.
This compatibility ensures that no matter your large-displacement vehicle type, the F3 Cylinder Head is a plug-and-play solution that works in harmony with your existing engine parts.
Exceptional Torque for Heavy Loads: The φ83 mm cylinder bore and 386CM discharge volume work together to deliver massive low-end torque (up to 50 N·m), making it easy to haul 150–200kg loads (on tricycles) or accelerate large motorcycles from a stop without straining the engine. This torque ensures consistent performance even when the vehicle is under maximum stress.
Thermal Stability for Sustained Use: The copper-infused aluminum alloy and ceramic coating excel at heat dissipation, keeping engine temperatures in check even during sustained high-RPM operation (e.g., long highway stretches or continuous cargo hauling). This prevents overheating-related power dips and extends the lifespan of other engine parts (like pistons and gaskets).
Reduced Maintenance for High-Use Scenarios: The reinforced materials and precision seal minimize wear on critical components, cutting down on unexpected repairs in industrial or high-mileage use. For business owners or enthusiasts who rely on their large-displacement vehicles for daily use, this means more time on the road and less money spent on replacement parts.