HONDA 18315-391-670 Muffler Exhaust Heat Shield Muff Protector

( Manufacturer Part Number: 18315-391-670 ), ( Mounting Style: Bolt-on ), ( Machine Type: Dual Sport Motorcycle ), ( Color: Black ), ( Material: Alloy Steel ), ( Vintage Part: Yes ), ( Placement On Vehicle: Exhaust ), ( Type: Muffler ), ( Oe/oem Part Number: 18315-391-670 Muffler Protector, 18315-391-670 Muffler, 8317-391-670 Heat Shield ), ( Features: Flat Black High Heat Ceramic Paint ), ( Finish: Matte ), ( Country Of Origin: Japan )

Review HONDA Xl 175 Oem Muffler Exhaust Heat Shield Muff Protector fits XL175 1976–1978

The **Honda 18315-391-670** is a meticulously crafted, high-performance exhaust system designed exclusively for the **1976 and 1978 Honda XL175 "XL"** models, ensuring an optimal blend of functionality, durability, and classic styling. This exhaust assembly features a **dual-tone, polished stainless steel construction**, combining a sleek, reflective finish with a protective heat shield to maintain both aesthetic appeal and longevity. The **muffler and muff protector** are engineered to minimize backpressure while maximizing flow efficiency, allowing the XL175 s reliable single-cylinder engine to breathe smoothly and deliver its characteristic smooth, throaty growl. The **heat shield** is strategically positioned to deflect heat away from critical components, reducing the risk of premature wear on surrounding parts and enhancing overall engine protection. Whether installed on a vintage trail bike meant for weekend rides or a restored classic for showroom display, this exhaust system ensures a balanced performance upgrade without compromising the bike s original character. Built to withstand the demands of off-road use, this genuine Honda part is constructed from premium materials, ensuring resistance to corrosion and wear, even under harsh conditions. Perfect for riders seeking both performance and authenticity, the **18315-391-670** exhaust system is a seamless fit for enthusiasts who appreciate the marriage of heritage engineering and modern reliability.

### **Pros and Cons of Buying a 1976-1978 Honda XL175 Muffler/Exhaust Heat Shield/Muff Protector (Part #18315-391-670)**

1. **Authentic Fit and Function** This is an original Honda part designed specifically for the XL175, ensuring a proper fit without modifications. It will integrate seamlessly with the stock exhaust system, maintaining proper function and performance.

2. **Durability and Longevity** Honda parts from this era were built to last, especially when properly maintained. The muffler and heat shield are made from stamped steel, which, while not as corrosion-resistant as modern coatings, is sturdy for its time.

3. **Sound and Performance Retention** Unlike aftermarket exhausts that may alter the bike s sound, this part keeps the stock tone of the XL175, which some riders prefer for its classic, understated growl.

4. **Ease of Installation** Since it s an OEM (Original Equipment Manufacturer) part, it should fit without requiring extensive modifications. Most riders with basic mechanical skills can install it themselves with standard tools.

5. **Resale Value Preservation** If you plan to sell or trade in the bike later, keeping original parts especially exhaust components can help maintain its collectible or vintage appeal.

6. **Compatibility with Classic Maintenance** The part is designed to work with the bike s original exhaust system, making it easier to perform routine maintenance like muffler checks, gasket replacements, or exhaust repairs without compatibility issues.

7. **Availability of Replacement Parts** While not as widely available as modern Honda parts, this component is still relatively easy to find through specialty motorcycle shops, eBay, or Honda parts dealers, especially if you re in a market with a strong vintage bike community.

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1. **Potential for Rust and Corrosion** Parts from this era were not treated with modern anti-corrosion coatings. If the original muffler or heat shield has rusted through, the new part may still be susceptible to corrosion if not properly maintained (e.g., regular cleaning, waxing, or rust inhibitors).

2. **Limited Aftermarket Support** Unlike newer Honda models, the XL175 has a smaller aftermarket, meaning fewer custom or upgraded options. If you re looking for performance-enhancing exhausts or modern materials, you ll need to source aftermarket parts separately.

3. **Sound May Not Be to Everyone s Taste** The stock exhaust sound on the XL175 is subtle and not as aggressive as modern or aftermarket exhausts. If you prefer a louder, sportier tone, this part won t alter the sound significantly.

4. **Potential for Gasket Failure** The gaskets in older exhaust systems can dry out or leak over time. While the part itself is solid, you may need to replace gaskets or clamps during installation to ensure a proper seal.

5. **Higher Cost Relative to Aftermarket Alternatives** While not excessively expensive, an OEM muffler/heat shield may cost more than a generic aftermarket replacement. However, the trade-off is authenticity and reliability.

6. **Weight** Older exhaust systems are heavier than modern lightweight alternatives. This may not affect performance much on a 175cc bike, but it s worth noting if you re concerned about weight distribution.

7. **Limited Warranty or No Warranty** Unlike new Honda parts, this used or reconditioned part may not come with a warranty. If it fails prematurely due to manufacturing defects, you ll be responsible for replacement costs.

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Buying the **1976-1978 Honda XL175 muffler/exhaust heat shield/muff protector (18315-391-670)** is a solid choice if you prioritize **authenticity, ease of installation, and long-term reliability** for your classic bike. It s ideal for riders who want to maintain the stock character of their XL175 without compromising function. However, if you re dealing with rust, corrosion, or prefer a louder exhaust, you may need to supplement this part with additional maintenance or aftermarket upgrades.

For most vintage enthusiasts, this is a **practical and cost-effective solution** especially if you re restoring or maintaining an original bike. If you re open to aftermarket options for sound or performance, you could explore alternatives, but the OEM part remains the safest bet for a seamless fit.

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- **Buy it if:** You want an **authentic, reliable, and easy-to-install** replacement for your XL175 s exhaust components. It s the best choice for preserving the bike s originality while ensuring proper function.

- **Consider alternatives if:** You re dealing with severe rust, want a louder exhaust, or are open to aftermarket parts for performance upgrades. In those cases, research **aftermarket mufflers with corrosion protection** or **modern exhaust systems** designed for the XL175.

- Inspect the part for **rust, cracks, or damage** before purchasing, especially if buying used.

- Replace **gaskets and clamps** during installation to prevent leaks.

- Apply a **corrosion inhibitor** (like CRC Rust Proofing) to extend the part s lifespan.

- If the bike sees off-road use, consider a **heavier-duty heat shield** for added protection.

For most riders keeping a **stock-sounding, well-maintained XL175**, this is the **best available option**.

Details:

Nice OEM HONDA part. The exhaust gasket appears to be in the muffler inlet. Like all my parts this part is guaranteed as described. 1976 - 1978 HONDA XL175 OEM Exhaust Muffler with Stainless Heat Shield Muff Protector.

Please look at the photos carefully, it is clean and ready to use now. Painted with two coats of High Temp Ceramic flat black paint. Photo of part number before paint, compliant with and US Forestry laws for spark arrest requirements. Not a cheap Chinese Rep, this is quality HONDA part made in Japan.

Packed carefully and ready to ship now. Removed from my 1976 Honda XL175. OEM HONDA parts. This part is guaranteed to work as described.

This vintage part is in good condition, clean and complete. No rust holes, dents or damage repair to muffler. Shipped UPS Ground or FedEx due to shipping size and weight. Please look at attached photos.

Guaranteed to be clean and delivered you as described. More parts if needed. Stainless Heat shield has a crack near the upper right side that is shown in photos, bolts up tight along with inner heat.

part #: 18315391670 prices

• $109.99-$155.00

specifications cyclemufflermo:

• for models: Xl175
• for makes: Honda
• for years: 1976-1978
• mpn: 18315-391-670
• mounting style: Bolt-on
• machine type: Dual Sport Motorcycle
• color: Black
• material: Alloy Steel
• vintage part: Yes
• placement on vehicle: Exhaust
• type: Muffler
• oe/oem part number: 18315-391-670 Muffler Protector, 18315-391-670 Muffler, 8317-391-670 Heat Shield
• features: Flat Black High Heat Ceramic Paint
• finish: Matte
• country of origin: Japan

shipping cyclemufflermo:

• class: Economy
• carrier: UPS, FedEx
• cost: $33.30
• service: UPS Ground Saver, FedEx Ground Economy
• type: Calculated
• transit: 9-13 Days

general cyclemufflermo:

• Motorcycle Scooter Parts Accessories > Exhaust Emission Systems > Silencers, Mufflers Baffles
• condition: Used

seller cyclemufflermo:

• rating: 100.0%
• city: Ponte Vedra, Florida
• # reviews: 656

returns cyclemufflermo:

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

payments cyclemufflermo:

• wallet: Apple-pay
• credit card: Discover
• other

offer cyclemufflermo:

• quantity: 1
• options: Ship-to-home
• started: May 9, 2026
• sold: 0
• availability: In Stock

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