YAMAHA 401-15421-00-00 Chain Sprocket Cover 77-83

( Part Type: Cover Chain Sprocket ), ( Oe/oem Part Number: 55y-15431-00-00 ), ( Country Of Origin: Japan ), ( UPC: 401154210000 )

Review YAMAHA 77-83 Chain Sprocket Cover fits DT100 MX100 MX125 MX175 YZ125

The **Yamaha DT100 Chain Sprocket Cover (Part Number: 401-15421-00-00)** is a precision-engineered, high-performance component designed exclusively for Yamaha s classic dual-sport and off-road motorcycles, including the iconic **MX100, MX125, MX175, and YZ125** models produced between **1977 and 1983**. Crafted from durable, heat-resistant materials, this sprocket cover serves as a critical protective barrier, shielding the chain and sprocket assembly from abrasive debris, moisture, and the harsh elements encountered during aggressive riding, trail exploration, or competitive motocross. Its robust construction ensures longevity while maintaining optimal chain tension and alignment, reducing wear on both the sprocket and chain key factors in preserving the reliability and performance of these legendary engines. The cover s ergonomic design allows for seamless installation, fitting snugly over the rear sprocket without interfering with the chain s smooth operation, even under high-stress conditions. Whether you re restoring a vintage bike to its original glory or maintaining a well-loved classic for daily rides, this OEM-quality sprocket cover guarantees a secure, leak-free seal, minimizing the risk of chain stretch or premature sprocket damage. Perfect for enthusiasts who demand authenticity and durability, this part is a must-have for any Yamaha owner seeking to extend the lifespan of their drivetrain while preserving the timeless spirit of these engineering marvels.

### **Pros and Cons of buying a Yamaha DT100 Chain Sprocket Cover (Part #77-83 DT100, Compatible with MX100, MX125, MX175, YZ125)**

1. **Direct Compatibility** This sprocket cover is specifically designed for Yamaha DT100 engines and is also compatible with several Yamaha MX models (MX100, MX125, MX175) and a Honda YZ125. This makes it a versatile choice if you own multiple bikes or plan to upgrade parts across different models.

2. **Durability** Yamaha parts are generally built to last, and this sprocket cover is likely made from high-quality materials to withstand the rigors of off-road riding, including exposure to dirt, debris, and minor impacts.

3. **Easy Installation** Being an OEM (Original Equipment Manufacturer) part, it should fit seamlessly without requiring extensive modifications. Most riders report that it snaps or bolts into place without difficulty, especially if the original is worn or damaged.

4. **Protection for the Chain** The primary function of a sprocket cover is to shield the chain and sprocket from dirt, rocks, and other debris, reducing wear and extending the lifespan of these critical components. A well-fitted cover helps prevent premature chain stretch and sprocket damage.

5. **Cost-Effective Replacement** Compared to aftermarket alternatives, this OEM part may offer better long-term value, especially if you prioritize reliability and fitment. Aftermarket parts can sometimes be cheaper but may lack the same durability or precision engineering.

6. **Maintenance Convenience** A properly fitted sprocket cover makes chain lubrication and inspection easier by keeping debris out of the drivetrain area, reducing the frequency of cleaning and maintenance.

7. **Aesthetic Consistency** If you prefer keeping your bike looking like new or maintaining a uniform appearance, an OEM sprocket cover ensures visual consistency with the rest of the bike s components.

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1. **Limited Compatibility Beyond Yamaha Models** While it fits several Yamaha MX bikes and a YZ125, it is **not universal**. If you own a different brand (e.g., Kawasaki, Suzuki, or other Honda models), this part will not work. Always double-check compatibility before purchasing.

2. **Potential for Wear Over Time** Like any plastic or rubber component, the sprocket cover can degrade due to UV exposure, heat, or physical stress. Over time, it may crack, warp, or become brittle, requiring replacement.

3. **Price Compared to Aftermarket Options** OEM parts from Yamaha can be more expensive than aftermarket alternatives. While aftermarket covers may not always match the quality of OEM parts, they can offer a budget-friendly solution if you re willing to compromise slightly on fit or longevity.

4. **Availability and Lead Times** OEM parts, especially older-model ones, may not always be in stock at local dealers. Online retailers might have longer shipping times, which could be inconvenient if you need the part urgently.

5. **Installation Challenges for Non-Mechanics** While generally straightforward, some riders may find the process slightly tricky if they lack experience with bike maintenance. Improper installation (e.g., misalignment or loose fit) could lead to premature wear or failure.

6. **Potential for Counterfeit Parts** When purchasing online, there s a risk of receiving a counterfeit or low-quality replica, especially from untrusted sellers. Always buy from reputable dealers (e.g., Yamaha-authorized parts stores, trusted online marketplaces) to avoid this issue.

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### **Conclusion**

The **Yamaha DT100 sprocket cover (77-83 DT100, compatible with MX100/125/175 and YZ125)** is a solid choice for riders who prioritize **reliability, direct compatibility, and OEM quality**. It offers excellent protection for the chain and sprocket while maintaining ease of installation. However, its **limited compatibility outside Yamaha/Honda models** and **potential long-term wear** are drawbacks to consider.

If you own one of the compatible bikes and need a replacement, this is a **recommended purchase** for its durability and fit. For riders on a tight budget or those who own non-Yamaha bikes, exploring **aftermarket alternatives** (e.g., from brands like **Givi, DID, or OEM clones**) may be worth investigating, provided they meet your quality standards.

- You own a Yamaha DT100, MX100, MX125, MX175, or Honda YZ125.

- You prefer OEM quality and direct compatibility.

- You want a reliable, long-lasting solution for chain protection.

- You own a different bike brand and need a universal fit.

- You re on a tight budget and can find a high-quality aftermarket cover.

- You re unsure about installation and prefer a dealer or mechanic to handle it.

**Final Verdict:** For its intended applications, this sprocket cover is a **strong, practical choice** that justifies its cost with durability and ease of use. Always verify compatibility and source from trusted sellers to avoid issues.

Details:

Good OEM cover. No deep scratches. Removed from a 1978 DT100. Guaranteed as Described.

77-83 Yamaha DT100 Chain Sprocket Cover MX100 MX125 MX175 YZ125 401-15421-00-00.

part #: 401154210000 prices

• $59.99-$188.26

specifications cyclevintagee:

• for models: Dt100, Mx100, Mx125, Mx175, Yz125
• for makes: Yamaha
• part type: Cover Chain Sprocket
• oe/oem part number: 55y-15431-00-00
• country of origin: Japan
• upc: 401154210000

returns cyclevintagee:

• policy: Returns Accepted
• paid by: Buyer
• time: 30 Days

shipping cyclevintagee:

• cost: $0.00
• class: Standard, Expedited
• service: USPS Ground Advantage, USPS Priority Mail
• type: Calculated
• transit: 3-7 Days
• carrier: USPS

seller cyclevintagee:

• # reviews: 10543
• rating: 99.9%
• city: Sun City, California

offer cyclevintagee:

• options: Ship-to-home
• availability: In Stock
• started: June 11, 2026
• quantity: 1
• sold: 0

payments cyclevintagee:

• credit card: Diners-club
• other
• wallet: Paypal

general cyclevintagee:

• condition: Used
• Parts Accessories > Motorcycle Scooter Parts Accessories > Other Motorcycle Scooter Parts Accessories

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