CG 4Fir Main Shaft Transmission

CG 4 Speed Main Shaft Transmission

🔧 Transmission Main Shaft · 4 Speed Shaft · CG125/CG150 Engine · Transmission Component

For CG125 · CG150 4-Stroke Air-Cooled Engines · 4 Speed Transmission

This is the CG 4 Speed Main Shaft Transmission, a high-quality replacement for the transmission system in CG125 and CG150 4-stroke air-cooled engines. Specifically designed for CG series engines, this main shaft is suitable for motorcycles, ATVs, and various other vehicles, making it the ideal choice for transmission repairs or performance restoration.

The main shaft is a core component of the transmission, responsible for transmitting power from the clutch through the gear set to the countershaft, ultimately driving the rear wheel. Manufactured from high-quality alloy steel with precision machining and heat treatment, this main shaft offers excellent strength, wear resistance, and fatigue resistance, ensuring smooth shifting and reliable operation.

This 4-speed main shaft fits vehicles equipped with CG125 and CG150 4-stroke air-cooled engines, including but not limited to:

• High-Quality Alloy Steel: Manufactured from premium alloy steel for high strength and excellent toughness.
• Precision Machining: Shaft journals and gears precision-ground for accurate dimensions and smooth operation.
• Carburized & Hardened: Surface carburized and hardened for high hardness, excellent wear resistance, and superior fatigue strength.
• OEM Specification: Manufactured to exact CG series engine factory specifications for perfect replacement of worn original components.
• 4-Speed Configuration: Specifically designed for 4-speed transmissions, matching original gear configuration.
• Restores Performance: Replacing worn main shaft eliminates shifting issues and noise, restoring proper transmission function.

🔧 Installation Guide

1. Remove the engine from the frame.
2. Split the engine crankcase to access the transmission assembly.
3. Remove the shift mechanism, shift forks, and gear sets.
4. Remove the old main shaft and inspect bearings and gears for wear.
5. Clean the transmission case and inspect bearing bores for wear.
6. Install the new main shaft along with the associated gears and bearings.
7. Check gear mesh clearance and verify proper shift mechanism operation.
8. Assemble the engine crankcase and tighten case bolts to specified torque.
9. Reinstall the engine, add fresh engine oil, and start the engine to test shifting function.
Important Note: Transmission disassembly and assembly involve precision components. Pay attention to gear orientation and clearance during installation. Professional installation is strongly recommended.

⚠️ Important Notice: This is the CG 4 Speed Main Shaft Transmission, designed for CG125 and CG150 4-stroke air-cooled engines with 4-speed transmissions.
Spec Confirmation: Before purchasing, verify your engine model and transmission speed count (4 speeds) to ensure compatibility.
Installation Note: Transmission disassembly and assembly involve critical engine components and require specialized tools and expertise. Professional installation is strongly recommended. Pay attention to gear orientation and clearance during installation.
Recommended Parts: When replacing the main shaft, it is recommended to inspect the countershaft, gears, bearings, and shift forks for wear, and replace them if necessary to ensure overall transmission performance. Product images are for reference only; actual product may vary.