C100 Main Shaft Assy - Manual
- Brand: Mortch Motor
- Product Code: MIC100-6039
- Product Viewed: 61
- Availability: Pre-Order Pre-Order
- Weight: 0.80kg
- Packing Size: 13.00 x 8.00 x 8.00cm
¥41.28
| Shipping To: |
C100 Main Shaft Assembly - Manual Clutch Type
⚙️ Main Shaft · Manual Transmission Input Shaft · Transmission Component
For Moped, Cub & ATV · Fits 139FMB, 147FMD, 147FMF, 150FMG engines
This is the C100 Main Shaft Assembly - Manual Clutch Type, a core power transmission component of the engine's transmission. It is suitable for Mopeds, Cub series, and ATVs, and fits engines including 139FMB, 147FMD, 147FMF, 150FMG, and similar models.
The main shaft assembly (manual clutch type) is installed in the transmission, meshing with the countershaft gears to distribute power from the clutch to each gear. Manufactured from high-strength alloy steel with precision-machined and heat-treated gears, it offers excellent wear resistance and fatigue strength. The manual clutch type main shaft works with the manual clutch, allowing the rider to control power engagement and disengagement via the clutch lever. This assembly is the ideal replacement when the original main shaft shows signs of gear wear, bearing damage, bending, or abnormal noise.
✨ Key Functions: Transmits power to transmission · Supports gear sets · Manual clutch compatible · Precision gear meshing · Smooth shifting
Product Name
Main Shaft Assembly - Manual Clutch Type
Engine Application
139FMB / 147FMD / 147FMF / 150FMG
Material
High-Strength Alloy Steel
Type
Manual Clutch Main Shaft
Heat Treatment
Carburizing · Surface Hardening
Gear Count
4-Speed (Standard)
⚠️ Important: Different engine displacements may use different main shaft configurations and gear counts. Please select the correct specification based on your engine model!
70cc / 90cc Specification
Displacement: 70cc / 90cc
Gear Count: 4-Speed
Shaft Length: Standard
Engine Models: 139FMB, 147FMD (Manual Clutch)
110cc / 125cc Specification
Displacement: 110cc / 125cc
Gear Count: 4-Speed
Shaft Length: Standard
Engine Models: 147FMF, 150FMG (Manual Clutch)
📌 Size Selection Guide: Different engine displacements may use different main shaft configurations and gear counts. To ensure accurate fitment, it is recommended to verify your original main shaft specifications or contact customer service.
This main shaft assembly fits the following engine models:
Engine Reference Information:
- 139FMB: 1P39FMB / 1P39QMB · 50cc-125cc universal engine
- 147FMD: 1P47FMD · 70cc-110cc engine
- 147FMF: 1P47FMF · 90cc-110cc engine
- 150FMG: 1P50FMG · 125cc-150cc engine
Note: This is the manual clutch version main shaft assembly. Please verify your transmission type is manual clutch before purchasing.
- Mopeds - Various 50cc-150cc manual clutch moped models (underbones, dirt bikes, etc.)
- Cub Series - Honda Cub and clone models with manual clutch
- ATVs - Small-engine manual clutch quad bikes / kids ATVs
- Dirt Bikes - Small manual clutch off-road motorcycles
- Other vehicles using 139FMB, 147FMD, 147FMF, 150FMG engines with manual clutch transmission
📌 Compatibility Note: This main shaft assembly is suitable for the manual clutch version of the engine models listed above. Please verify your transmission type is manual clutch before purchase.
🖐️ Manual Clutch Type
Rider controls clutch engagement/disengagement via clutch lever
✔ Strong driving feel
✔ Ideal for off-road and racing
✔ Rider controls shift timing
⚙️ Automatic Clutch Type
Centrifugal clutch operates automatically, no manual input required
✔ Easy operation
✔ Ideal for city commuting
✔ No clutch lever needed
💡 Purchase Tip: Please verify whether your vehicle has manual or automatic clutch, and select the corresponding main shaft assembly. They are not interchangeable.
🔄 Power Distribution
Transmits power from the clutch to all gear sets, serving as the core transmission shaft.
⚙️ Gear Support
Supports all gear sets, ensuring proper meshing and smooth power transfer.
🖐️ Manual Clutch Compatible
Designed for manual clutch systems, works with clutch assembly for rider-controlled shifting.
🛡️ Shift Quality
Gear precision directly affects shifting smoothness and riding comfort.
⚠️ Main Shaft Failure Symptoms: Transmission noise (gear whine or knocking), difficult shifting, gear jumping, uneven power delivery, noise changes with clutch lever operation. If these occur, inspect and replace the main shaft assembly and matching gears.
- Transmission Noise: Rhythmic gear noise or knocking from the transmission area that changes with engine RPM.
- Difficult Shifting: Stiff or rough shifting, difficulty engaging gears.
- Gear Jumping: Unexpected disengagement from gear during acceleration or deceleration.
- Uneven Power Delivery: Delayed or jerky power response during acceleration.
- Clutch-Related Noise: Noise reduces or disappears when clutch lever is pulled; noise returns when lever is released.
- Gear Wear or Damage: Inspection reveals worn, pitted, or chipped gear teeth, or damaged bearings.
If you experience these symptoms, inspect the main shaft assembly and countershaft assembly, and replace if necessary.
- OEM Specifications: Manufactured to original gear parameters and dimensions for perfect fitment.
- High-Strength Alloy Steel: Made from premium alloy steel with excellent strength and toughness.
- Precision-Machined Gears: Precision hobbing and grinding for smooth engagement and low noise.
- Carburizing & Hardening: Gear teeth undergo carburizing and hardening for high surface hardness and superior wear resistance.
- Manual Clutch Design: Specifically designed for manual clutch transmissions, works with manual clutch assembly.
- Direct Replacement: Directly replaces worn or damaged original main shaft assembly without modification.
🔧 Installation Tip
1. Replacing the main shaft assembly requires disassembling the engine transmission; professional installation is recommended.
2. Thoroughly clean the transmission case and inspect bearing bores for wear before installation.
3. Inspect countershaft gears for wear; it is recommended to replace the countershaft assembly simultaneously.
4. Use proper tools to install bearings; avoid hammering to prevent damage.
5. Pay attention to gear orientation during installation; ensure shift fork grooves are properly aligned.
6. Tighten bearing retaining bolts and shift mechanism screws to the specified torque.
7. After installation, manually rotate the main shaft to check smooth gear engagement through all gears.
8. Add appropriate transmission oil, start the engine, and verify normal operation in all gears.
9. Adjust clutch cable free play to the specified value.
Specification Confirmation: Before purchase, please verify your transmission type is manual clutch. Manual clutch and automatic clutch main shafts are not interchangeable. Contact customer service if you have any questions.
Installation Notes: Pay attention to gear orientation and proper bearing installation. It is recommended to inspect the countershaft assembly simultaneously. Images are for reference only. The actual product may vary.
- Please verify that this part fits your specific vehicle model and year. Many vehicles share similar names but use different components depending on year or market region.
- We strongly recommend cross-checking with your vehicle's owner's manual or contacting us for confirmation before placing your order.
- Product images, measurements, and descriptions are for reference only. Slight variations in color or appearance may occur due to manufacturing batches or photography lighting—functional specifications remain identical to the ordered part.
- Professional installation is mandatory. Mortch Motor assumes no liability for damages, injuries, or losses resulting from improper installation, misuse, unauthorized modification, or abnormal operation.
- All listed prices EXCLUDE shipping costs, import duties, taxes, and customs clearance fees. These charges (if applicable) are determined and collected by your local customs authority and are solely the buyer's responsibility.
- In case of return due to unpaid duties/taxes or refusal to clear customs, the buyer shall bear the original shipping cost, return shipping fees, and any associated administrative charges deducted from the refund.


Thank You









