Factory-backed forged pistons, connecting rods, crankshaft assemblies, and cylinders — engineered for the next generation of championship-winning motorcycles. From concept to production, we deliver world-class quality for racing brands worldwide.
Forged Pistons · Connecting Rods · Crankshafts · Cylinders
We do not simply manufacture parts — we engineer complete rotating assembly solutions for racing motorcycles. Our 20+ years of experience span material science, precision forging, CNC machining, thermal treatment, and quality assurance — all integrated under one roof.
"Most suppliers can make a piston. Few can engineer a complete rotating assembly — piston, rod, crank, and cylinder — as a matched system, optimized for a specific engine platform and power goal. That is the difference between a parts vendor and a true engineering partner."
In-house forging, CNC machining, heat treatment, shot peening, MPI inspection, and surface coating — full control of the entire production chain. No outsourcing, no compromise on quality.
2618-T6 / 4032-T6 forged pistons · 4340 / 300M / Titanium connecting rods · 40Cr forged crankshafts · 20CrMo rods · Ni-SiC electro-ceramic cylinder plating. Each material selected and validated for its specific application.
FEA analysis · 3D modeling · Prototype machining · Testing support. 10-set minimum for custom specs. Engineer-direct consultation — your concept to production drawing in 3–7 days.
From individual components to complete rotating assemblies — our manufacturing capability covers the full spectrum of high-performance motorcycle engine parts.
Every component passes through our integrated production line, with quality verification at every stage — from raw material to finished product.
Precision hot forging of aluminum and steel alloys. Optimized grain flow structure for maximum component strength and fatigue life.
High-accuracy CNC machining maintaining tolerances down to ±0.003mm. Multi-axis capability for complex geometries and custom profiles.
T6 solution & aging for aluminum alloys. Carburizing, nitriding, and through-hardening for steel components. Fully controlled in-house.
Shot peening · MPI crack detection · 100% dimensional inspection · Hardness testing · Metallurgical analysis · Full batch traceability documentation.
Every component is engineered to perform as part of an integrated rotating assembly — not as an isolated part. This system-level approach is what sets our engineering apart.
High-strength 40Cr forged crankshaft webs with induction-hardened crank pins. Precision balanced for high-RPM racing engines up to 14,000+ RPM. Full stroke customization and multi-piece assembly options available.
OEM-grade alloy steel connecting rods engineered for fatigue resistance. Fracture-split cap design for precise bearing alignment. Shot-peened fillets reduce stress concentration. Available with ARP2000 / L19 / 625+ bolts.
High-silicon AC9B cast pistons for OEM-grade durability and 2618/4032 forged pistons for extreme performance applications. Multiple ring pack configurations, coating options, and compression ratios available.
Advanced nickel-silicon carbide electro-ceramic plated cylinders providing exceptional wear resistance, lower friction, and superior heat transfer versus traditional cast iron liners. Race-proven in off-road, motocross, and enduro environments.
What makes JA-Modified the right partner for racing motorcycle brands seeking world-class engine components.
Pistons, rods, cranks, and cylinders — matched as a system from one engineering team. No cross-brand compatibility issues, optimized together for maximum performance.
Components tested in motocross, enduro, track, and off-road environments. From 85cc mini bikes to 1000cc+ superbikes — proven reliability at the limit.
Custom orders from just 10 sets. Ideal for prototype development, limited-edition models, and racing programs. Engineer-direct communication from concept to delivery.
World-class engineering and quality standards, with the responsiveness and flexibility of a direct factory partnership. No middlemen, no minimum volume commitments.
Concept to drawing in 3–7 days. Production in 4 weeks for custom orders. Rapid iteration for development programs where time-to-track matters.
Full material certification with mill certificates. Every batch documented with dimensional inspection, MPI crack detection, and hardness testing results.
We have developed and manufactured components for a wide range of motorcycle engines. If your platform is not listed, our engineering team can develop a custom solution tailored to your specifications.
Whether you are developing a new race platform or upgrading an existing model — our engineering team is ready to partner with you. Contact us to discuss your project requirements.
Contact Our Engineering Team →