HARLEY-DAVIDSON 42381-87 Rear Cover Master Cylinder

( Brand: Harley-davidson ), ( Manufacturer Part Number: 42381-87 ), ( Part Type: Cover ), ( Compatible Make: See Description )

Review HARLEY DAVIDSON Rear Master Cylinder Cover fits SPORTSTER

The **Harley-Davidson 42381-87 Rear Master Cylinder Cover** is a meticulously engineered component designed exclusively for the iconic Sportster lineup, ensuring both form and function in perfect harmony. Crafted from high-quality, durable materials, this cover is engineered to withstand the rigorous demands of daily riding, from spirited cruises to the most challenging off-road adventures. Its sleek, aerodynamic design not only enhances the aesthetic appeal of the Sportster s rear suspension area but also contributes to a streamlined, aggressive stance that reflects the bold spirit of Harley-Davidson s legacy. The cover is precision-fitted to the rear master cylinder, providing a seamless integration that minimizes air resistance while maintaining optimal cooling for the hydraulic system. Constructed with a robust, corrosion-resistant finish, it is built to endure the elements, ensuring longevity even in harsh weather conditions. Whether you re a seasoned rider seeking to preserve the pristine look of your Sportster or a performance enthusiast prioritizing functionality, this master cylinder cover delivers a perfect blend of style and reliability. Its precise engineering aligns with Harley-Davidson s commitment to craftsmanship, making it an essential accessory for maintaining both the visual integrity and mechanical efficiency of your motorcycle.

**Pros and Cons of buying a Harley-Davidson 42381-87 Rear Master Cylinder Cover (Sportster)**

The Harley-Davidson 42381-87 rear master cylinder cover is a genuine OEM (Original Equipment Manufacturer) part, which means it is designed specifically for your Sportster model. This offers several advantages:

1. **Perfect Fit and Functionality** Since it is manufactured by Harley-Davidson, the part is engineered to match the exact specifications of your bike, ensuring proper fitment and performance. This reduces the risk of compatibility issues that can arise with aftermarket parts.

2. **High-Quality Materials** Harley-Davidson parts are built to last, using durable materials that withstand the stresses of daily riding. The cover is likely made from sturdy plastic or metal, depending on the model, and is designed to protect internal components from dirt, debris, and moisture.

3. **Reliability and Durability** Genuine parts are less likely to fail prematurely compared to cheaper aftermarket alternatives. This can save you from unexpected repairs and downtime, especially if your bike is used for long rides or in harsh conditions.

4. **Warranty Coverage** Purchasing an OEM part may entitle you to warranty coverage from Harley-Davidson or the dealer where you buy it. This can provide peace of mind in case the part fails due to a manufacturing defect.

5. **Aesthetic Consistency** The part maintains the original look of your Sportster, which is important if you value the bike s classic or stock appearance. Aftermarket parts may not always match the factory design, which could affect resale value or personal satisfaction.

6. **Easier Maintenance and Repairs** When working on your bike, having genuine parts ensures that mechanics and DIYers can easily identify and install the correct components without confusion. This simplifies maintenance tasks like fluid changes or brake system servicing.

7. **Resale Value** If you decide to sell your Sportster in the future, having original or high-quality parts can make the bike more appealing to buyers who prefer stock or well-maintained motorcycles.

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1. **Higher Cost** Genuine Harley-Davidson parts are typically more expensive than aftermarket alternatives. The price may be significantly higher, especially if the part is no longer in active production or requires special ordering. This can be a financial burden for riders on a tight budget.

2. **Limited Availability** Some OEM parts, particularly older or discontinued models, may be hard to find. Harley-Davidson does not always stock every part indefinitely, which could lead to delays in obtaining the cover. You may need to order it from a dealer, a specialty parts store, or an online marketplace, which could take time.

3. **Longer Lead Times** Even if the part is available, ordering from a dealer or Harley-Davidson s official channels may result in longer wait times compared to aftermarket suppliers, which often have faster shipping options.

4. **Overkill for Minor Repairs** If the rear master cylinder cover is damaged or worn but not critical to the bike s operation, some riders may opt for a cheaper aftermarket replacement or even a DIY fix (such as a repair kit) instead of investing in a full OEM part. In such cases, the cost may not justify the purchase.

5. **Potential for Overstock or Used Parts** When purchasing from dealers, there is a risk of buying a used or overstocked part that may have been previously installed or exposed to wear. While Harley-Davidson parts are generally reliable, used parts may not come with the same warranty or guarantee of newness.

6. **Environmental and Ethical Concerns** Some riders prefer to avoid supporting industries that may have environmental or ethical issues. While Harley-Davidson is a well-established company, purchasing OEM parts contributes to the demand for new manufacturing, which may not align with the values of eco-conscious riders.

7. **Aftermarket Alternatives May Be Sufficient** For many riders, aftermarket parts offer comparable quality at a fraction of the cost. Many reputable manufacturers produce high-quality replicas or improved versions of OEM parts that fit perfectly and perform just as well. If the cover is purely cosmetic or not a critical safety component, aftermarket options could be a practical choice.

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The Harley-Davidson 42381-87 rear master cylinder cover is an excellent choice if you prioritize **fitment, reliability, and long-term durability** for your Sportster. It is the safest and most consistent option for maintaining your bike s original integrity, especially if you plan to keep the motorcycle for years or sell it in the future. The part s high quality and warranty coverage make it a sound investment for riders who value performance and peace of mind.

However, if **budget constraints, availability issues, or the part s non-critical nature** are concerns, aftermarket alternatives may be a more practical solution. Aftermarket parts can offer similar performance at a lower cost, and for non-safety-related components like this cover, the difference in quality may be negligible for most riders.

Ultimately, the decision depends on your **priorities, budget, and how critical the part is to your riding experience**. If you can afford it and value OEM components, the Harley-Davidson part is the best choice. If you re looking to save money without sacrificing too much quality, a well-reviewed aftermarket alternative could be a viable substitute.

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- You want the absolute best fit and reliability for your Sportster.

- You plan to keep the bike long-term or intend to sell it with minimal modifications.

- You can afford the higher cost and are willing to wait for shipping if necessary.

- You value the aesthetic consistency of OEM parts.

- You are on a tight budget and can find a reputable aftermarket part with good reviews.

- The cover is not a critical safety component, and you prioritize cost savings.

- You can t find the OEM part easily or are willing to wait for it, and aftermarket options are readily available.

For most riders, the **OEM part is the best long-term choice**, but always weigh your options based on your specific needs and circumstances. If you decide to go with an aftermarket part, research thoroughly to ensure it meets your quality expectations.

Details:

The part number 42381-87 ensures compatibility with the specified make and year of Sportster model's, making it a reliable choice for motorcycle maintenance customization. Made by the manufacturer itself, this cover is a perfect fit for those seeking quality and authenticity in their motorcycle parts. The 42381-87 Rear Master Cylinder Cover is a genuine Harley-Davidson part specifically designed for Sportster motorcycles.

part #: 4238187 prices

• $9.95-$156.75

specifications cyclevintagee:

• for models: Sportster
• for makes: Harley
• brand: Harley-davidson
• mpn: 42381-87
• part type: Cover
• compatible make: See Description

returns cyclevintagee:

• policy: No Returns

seller cyclevintagee:

• city: Kenosha, Wisconsin
• # reviews: 63
• rating: 100.0%

payments cyclevintagee:

• wallet: Google-pay
• other
• credit card: Diners-club
• money order

offer cyclevintagee:

• sold: 0
• best offers: True
• options: Ship-to-home
• quantity: 1
• availability: In Stock
• started: March 7, 2026

shipping cyclevintagee:

• type: Calculated
• carrier: USPS
• transit: 5-11 Days
• service: USPS Ground Advantage
• cost: $5.07
• class: Standard

general cyclevintagee:

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

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