C100 Timing Chain

C100 Timing Chain

🔗 Timing Chain · Cam Chain · Valve Train

For Moped, Cub & ATV · Fits 139FMB, 147FMD, 147FMF, 150FMG engines

This is the C100 Timing Chain, a critical component of the engine's valve train. It is suitable for Mopeds, Cub series, and ATVs, and fits engines including 139FMB, 147FMD, 147FMF, 150FMG, and similar models.

The timing chain (cam chain) is installed between the crankshaft sprocket and camshaft sprocket, transmitting rotational power from the crankshaft to the camshaft with precision, ensuring valves open and close at the correct times. Manufactured from high-strength alloy steel, the chain links are precision-stamped and heat-treated for excellent tensile strength, wear resistance, and fatigue resistance. Built to OEM specifications, it is the ideal replacement when the original timing chain is worn, stretched, or broken.

This timing chain fits the following engine models:

• Mopeds - Various 50cc-150cc moped models (underbones, scooters, etc.)
• Cub Series - Honda Cub and clone models
• ATVs - Small-engine quad bikes / kids ATVs
• Dirt Bikes - Small off-road motorcycles
• Other vehicles using 139FMB, 147FMD, 147FMF, 150FMG engines

• Unusual Noise: Rattling, grinding, or slapping sound from the timing chain area that changes with engine RPM.
• Chain Stretch: Chain appears loose upon inspection; tensioner is fully extended but cannot maintain proper tension.
• Power Loss / Poor Acceleration: Chain stretch causes timing deviation, leading to incorrect valve timing and reduced power output.
• Rough Idle / Hard Starting: Incorrect timing affects ignition timing and valve overlap.
• Chain Jump or Breakage: Severe wear or fatigue may cause chain jump or breakage, potentially resulting in catastrophic engine damage.
• Timing Marks Misalignment: Crankshaft and camshaft timing marks cannot be aligned properly.

If you experience these symptoms, inspect the timing chain and related components (sprockets, tensioner, guides) and replace as necessary.

• OEM Specifications: Manufactured to original dimensions and pitch for perfect meshing with timing sprockets.
• High-Strength Alloy Steel: Made from premium alloy steel with precision stamping and heat treatment for excellent tensile strength.
• Precision Roller Structure: Rollers and link plates are precisely matched for smooth operation, low noise, and minimal wear.
• Wear & Fatigue Resistant: Surface treatment provides excellent wear resistance and fatigue life for long service durability.
• Direct Replacement: Directly replaces worn or stretched original timing chain without modification.

🔧 Installation Tip

1. Replacing the timing chain requires removing the engine side cover, magneto, timing chain tensioner, and other components; professional installation is recommended.
2. Thoroughly clean the timing chain chamber to remove sludge and debris before installation.
3. It is recommended to inspect and replace the timing sprockets, tensioner, and guides simultaneously to ensure complete timing system reliability.
4. During installation, carefully align the crankshaft and camshaft timing marks to ensure correct valve timing.
5. Before installing the tensioner, compress and lock it according to specifications, then release tension after proper installation.
6. After installation, manually rotate the crankshaft several times to verify timing marks remain aligned and the chain runs smoothly without noise.
7. Start the engine and listen for any abnormal noise from the timing area to confirm proper tension.

⚠️ Important Notice: This is a C100 timing chain suitable for Mopeds, Cubs, ATVs, and vehicles using 139FMB, 147FMD, 147FMF, 150FMG engines. Proper alignment of timing marks is critical during installation to prevent engine damage. As link counts may vary across different engine batches, please verify your original chain specifications before purchase. Images are for reference only. The actual product may vary.