C100 Drive Sprocket 17T

Brand: Mortch Motor
Product Code: MIC100-6041-17

Product Viewed: 190

Availability: Pre-Order

Weight: 0.13kg

Packing Size: 5.00 x 5.00 x 2.00cm

0 reviews / Write a review

US$1.30 5 SOLD

Shipping To：

More Quotes

C100 428 17 Teeth Steel Front Sprocket

🔗 Front Sprocket · Drive Sprocket · Countershaft Sprocket · Transmission Component

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

📋 Product Overview

This is the C100 428 17 Teeth Steel Front Sprocket, a critical component of the engine's drive system. It is suitable for Mopeds, Cub series, Dirty Bikes, and ATVs, and fits engines including 139FMB, 147FMD, 147FMF, 150FMG, and similar models.

The front sprocket (drive sprocket/countershaft sprocket) is mounted on the transmission output shaft and works with the rear sprocket and chain to transfer engine power to the rear wheel. Manufactured from high-strength steel with precision-machined and heat-treated teeth, it offers excellent wear resistance and impact strength. The 428 chain specification is the standard motorcycle drive chain size, and the 17-tooth design provides higher top speed and better fuel economy during highway cruising. This sprocket is the ideal replacement when the original shows signs of tooth wear, chipped teeth, or abnormal noise.

✨ Key Functions: Transmits power to rear wheel · Works with chain drive · Determines gear ratio · Wear resistant & impact resistant · Improves highway cruising economy

📐 Specifications

Product Name

428 17T Steel Front Sprocket

Engine Application

139FMB / 147FMD / 147FMF / 150FMG

Chain Size

428

Tooth Count

17 Teeth

Material

High-Strength Steel · Heat Treated

Position

Transmission Output Shaft

⚙️ Sprocket Tooth Count Performance Impact

📈 14T Front Sprocket

Better acceleration, strong low-end power, excellent hill climbing

✔ Ideal for city commuting
✔ Great for heavy loads and hills
✔ Quick throttle response

📉 17T Front Sprocket

Higher top speed, better fuel economy at highway speeds, lower engine RPM

✔ Ideal for long-distance riding
✔ Better highway fuel economy
✔ Lower engine noise
✔ Slightly reduced low-end acceleration

📌 Tooth Count Recommendation: The 17-tooth front sprocket provides higher top speed and better highway cruising economy, ideal for long-distance riders. For better acceleration, consider 14T front sprockets.

📊 Tooth Count Comparison (Based on 35T Rear Sprocket)

Front Sprocket	Rear Sprocket	Final Drive Ratio	Performance Characteristic
14T	35T	2.50	Strong acceleration, excellent hill climbing
17T	35T	2.06	Higher top speed, better highway fuel economy

💡 Note: A lower final drive ratio provides higher top speed and lower engine RPM at the same road speed; a higher ratio provides better acceleration. The 17-tooth front sprocket effectively reduces engine RPM during highway cruising, improving comfort and fuel economy.

🔧 Compatible Engine Models

This front sprocket fits the following engine models:

139FMB

147FMD

147FMF

150FMG

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 sprocket is designed for C100/universal countershaft spline specifications and uses 428 chain size. The 17-tooth design is ideal for riders seeking higher top speed and better highway cruising economy.

🛵 Compatible Vehicles

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

📌 Compatibility Note: This front sprocket is suitable for the engine models listed above. Before installation, please verify your vehicle uses 428 chain and the countershaft spline is C100/universal type. The 17-tooth design is ideal for long-distance riding and higher top speed.

⚙️ Importance of Front Sprocket

🔗 Power Transmission

Transmits transmission output power to the rear wheel via the chain.

⚙️ Gear Ratio Adjustment

The 17-tooth design provides a lower final drive ratio, increasing top speed and highway fuel economy.

🛡️ Wear Critical

The front sprocket has fewer teeth and spins faster, wearing faster than the rear sprocket.

🔧 Chain Compatibility

Precision tooth profile directly affects chain life and smooth power transfer.

⚠️ Front Sprocket Failure Symptoms: Drive system noise (clicking from chain area), jerky acceleration, chain jumping, worn teeth (hook-shaped), abnormal chain tension. If these occur, inspect and replace the front sprocket and chain.

⚠️ Common Failure Symptoms

Drive Noise: Rhythmic clicking or grinding from the chain area that changes with vehicle speed.
Jerky Acceleration: Power delivery feels uneven with shock during acceleration.
Chain Jumping: Chain runs unevenly on the sprocket, visible jumping.
Worn Teeth: Inspection reveals severely worn, hook-shaped, or pointed teeth.
Abnormal Chain Tension: Chain becomes loose quickly even after adjustment.
Broken Teeth: Severe cases may cause tooth breakage and power loss.

If you experience these symptoms, inspect the front sprocket and chain, and replace if necessary. For best results, replace the chain and rear sprocket simultaneously.

✨ Product Features

OEM Specifications: Manufactured to original tooth profile and dimensions for perfect chain engagement.
High-Strength Steel: Made from premium alloy steel with excellent strength and impact resistance.
Precision-Machined Teeth: Precision machining ensures accurate tooth profile for smooth engagement and low noise.
Heat Treated: Teeth are heat-hardened for superior wear resistance and long service life.
428 Chain Size: Standard motorcycle drive chain specification, widely compatible.
17-Tooth Design: Provides higher top speed and better highway cruising economy, ideal for long-distance riding.
Direct Replacement: Directly replaces worn or damaged original front sprocket without modification.

🔧 Installation Tip

1. Replacing the front sprocket requires removing the left engine sprocket cover; professional installation is recommended.
2. Clean the countershaft splines and sprocket mounting surface thoroughly before installation.
3. Inspect the countershaft splines for wear; have them repaired if damaged.
4. Align the sprocket with the locating tab or spline groove during installation.
5. Tighten the sprocket retaining nut or bolt to the specified torque.
6. It is recommended to replace the chain and rear sprocket simultaneously for optimal performance and longevity.
7. After installation, adjust chain tension to specification (typically 15-25mm free play).
8. Start the vehicle and check for abnormal noise; verify smooth chain operation.
9. After switching to a 17-tooth sprocket, you may need to adjust chain length to ensure sufficient adjustment range.

⚠️ Important Notice: This is a C100 428 17-tooth steel front sprocket, suitable for Mopeds, Cubs, Dirty Bikes, ATVs, and vehicles using 139FMB, 147FMD, 147FMF, 150FMG engines.
Specification Confirmation: Please verify your vehicle uses 428 chain and the countershaft spline is C100/universal type. The 17-tooth design provides higher top speed and better highway cruising economy, ideal for long-distance riders.
Important Note: After switching to a 17-tooth sprocket, acceleration will be slightly reduced. Choose the appropriate tooth count based on your riding needs. Pay attention to sprocket orientation and torque specifications. It is recommended to replace the chain and rear sprocket simultaneously. Images are for reference only. The actual product may vary.

🔧 Compatibility Notice

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 Disclaimer

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.

💰 Import Duties & Taxes

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.

📌 Order Confirmation: By completing your purchase, you acknowledge that you have read, understood, and agreed to all terms above. For any questions, please contact our support team prior to ordering.