1. Motorcycle Silencers, Mufflers & Baffles For Sale
  2. sku: 15559181113778603
  3. YAMAHA YMS400

YAMAHA YMS400 Exhaust Header Head Pipe Muffler Spark

fits model: Yz400, Yz400f. make: Yamaha. year: 1999–2001.

Yms400 Yamaha Exhaust Header Head Pipe Muffler Spark Yz400 Yz400f 1999 2000 2001 Oem

( Manufacturer Part Number: YMS400 ), ( Placement On Vehicle: Exhaust ), ( Type: Muffler ), ( Country Of Origin: Japan )

Review YAMAHA Exhaust Header Head Pipe Muffler Spark Oem fits YZ400 YZ400F 1999–2001

The **Yamaha YMS400 Exhaust Header Head Pipe Muffler Spark** is a meticulously engineered aftermarket exhaust system designed specifically for the **1999, 2000, and 2001 Yamaha YZ400/YZ400F**, offering a seamless blend of performance enhancement, durability, and attention to detail. Crafted from high-quality **409 stainless steel**, this exhaust system is built to withstand the rigors of off-road riding while delivering a noticeable boost in power and responsiveness. The **YMS400** features a **direct-fit head pipe and muffler assembly**, eliminating the need for modifications to the stock exhaust ports, ensuring a clean, straightforward installation that even intermediate mechanics can tackle with confidence. The system incorporates a **precision-welded design**, with smooth, polished internals that reduce turbulence and maximize airflow, allowing the engine to breathe more efficiently and extract every ounce of potential from the stock Yamaha powerplant.

At the heart of this exhaust system lies a **high-flow spark arrestor**, engineered to meet DOT and EPA regulations while maintaining optimal exhaust flow. The **muffler section** is constructed with a **dual-chamber design**, balancing power output with a deep, aggressive growl that turns heads on the trail. The **head pipe** is precision-machined to match the stock Yamaha exhaust flange, ensuring a perfect seal and preventing any exhaust leaks that could compromise performance or safety. The **spark arrestor** is not only compliant with legal requirements but is also built to last, featuring a **durable steel mesh** that resists clogging from debris while maintaining a consistent exhaust note.

One of the standout features of the **YMS400** is its **universal compatibility** with the YZ400/YZ400F, making it an ideal upgrade for riders looking to enhance their bike s performance without sacrificing reliability. The system is designed to handle the demands of aggressive riding, from steep climbs to high-speed descents, delivering a **noticeable increase in horsepower and torque** while also improving throttle response. The **stainless steel construction** ensures resistance to corrosion, rust, and heat, making this exhaust system a long-term investment that will maintain its performance and appearance even after years of hard use. Whether you're tearing up the trails, competing in motocross events, or simply looking to give your YZ400 a more aggressive sound and better power delivery, the **Yamaha YMS400 Exhaust Header Head Pipe Muffler Spark** is a premium choice that delivers on both performance and style.

### **Pros and Cons of Buying a Yamaha YMS400 Exhaust System for a 1999-2001 YZ400/YZ400F**

#### **Pros:**

1. **Performance Gains** The YMS400 is designed to improve exhaust flow, which can enhance horsepower and throttle response, especially when paired with a high-performance air filter or carburetor setup. Many riders report noticeable mid-range and top-end power increases.

2. **Lightweight Construction** Made from high-quality stainless steel, the YMS400 is lighter than stock headers, reducing unsprung weight and improving handling. This is particularly beneficial for motocross and off-road riding.

3. **Improved Exhaust Note** The system produces a deeper, more aggressive exhaust tone compared to the stock setup, which many riders prefer for both aesthetics and feedback.

4. **Durability** Yamaha s YMS series is known for its robust construction, capable of handling the stresses of aggressive riding without excessive wear.

5. **Compatibility** The YMS400 is specifically designed for the YZ400/YZ400F, ensuring a proper fit without modifications. It includes a head pipe, muffler, and headers in one package, simplifying installation.

6. **Aftermarket Support** The YMS400 is a well-documented system with available gaskets, clamps, and tuning recommendations from Yamaha and third-party sources.

7. **Potential for Further Modifications** The improved exhaust flow can allow for additional upgrades, such as a high-flow carburetor or intake system, to further enhance performance.

---

#### **Cons:**

1. **Cost** The YMS400 is more expensive than stock exhaust systems or basic aftermarket alternatives. For a complete system (headers, head pipe, muffler), prices can range significantly depending on condition and seller.

2. **Installation Complexity** While not overly difficult, installing the YMS400 requires removing the stock exhaust, which involves heat treatment of the head pipe to prevent warping. This may require professional help or careful DIY work.

3. **Tuning Required** Simply bolting on the YMS400 may not yield optimal results without adjusting the carburetor (e.g., switching to a larger jet or using a power valve). Neglecting tuning can lead to rough idle, poor low-end power, or even engine damage if the mixture is too rich.

4. **Weight Transfer and Handling** While the YMS400 is lighter than stock, some riders report slight changes in weight distribution, particularly if the muffler is mounted differently. This is usually minor but worth considering for competitive riders.

5. **Noise Regulations** Depending on local laws, the louder exhaust note from the YMS400 may require additional muffling or compliance with noise ordinances, which could negate some of the performance benefits.

6. **Potential for Leaks** Like any aftermarket exhaust, the YMS400 can develop leaks at gaskets or welds over time, especially if not properly maintained. Regular inspections are recommended.

7. **Stock vs. Upgraded Trade-Off** If the bike is otherwise stock, the gains from the YMS400 may be modest unless paired with other modifications (e.g., clutch, crankshaft, or suspension upgrades).

---

### **Conclusion:**

The Yamaha YMS400 is a high-quality, performance-focused exhaust system that offers measurable gains in power, weight reduction, and exhaust tone for the 1999-2001 YZ400/YZ400F. It is particularly well-suited for riders who prioritize aggressive riding, competitive performance, or a more aggressive exhaust sound. However, the cost, installation effort, and necessity for tuning must be carefully considered.

For riders who are already running other performance upgrades (e.g., clutch, crankshaft, or suspension), the YMS400 will likely provide the most noticeable benefits. For stock or lightly modified bikes, the gains may be modest, and the expense may not be justified unless exhaust tone and minor power improvements are the primary goals.

---

### **Recommendation:** - **Buy the YMS400 if:**

- You are running or plan to run other performance upgrades (e.g., clutch, crankshaft, or high-flow carburetor).

- You prioritize a deeper exhaust note and improved throttle response.

- You are willing to invest in tuning (carburetor adjustments, power valve, or ECU flashing if applicable).

- You prefer a lightweight, durable exhaust system that enhances handling.

- **Avoid or consider alternatives if:**

- You are on a tight budget and only want minor power gains.

- You are not comfortable with installation or tuning.

- Your local noise laws restrict loud exhausts, as the YMS400 is significantly louder than stock.

- You prefer a simpler, lower-cost upgrade (e.g., a header-only setup or a basic aftermarket muffler).

For those who decide to proceed, purchasing from a reputable dealer or seller with a warranty is highly recommended to ensure quality and avoid counterfeit or damaged parts. Additionally, consulting with experienced riders or mechanics familiar with the YZ400 platform can provide valuable insights on tuning and installation tips.

Details:

Removed from 1999 Yamaha YZ400F. Used with a few minor dings and scratches but overall good usable condition. Spark Arrest screen is clean and in good shape.

part #: yms400 price

  • $149.99

specifications cyclemufflermo:

  • for models: Yz400, Yz400f
  • for makes: Yamaha
  • for years: 1999-2001
  • mpn: Yms400
  • placement on vehicle: Exhaust
  • type: Muffler
  • country of origin: Japan

offer cyclemufflermo:

  • sold: 0
  • started: April 13, 2026
  • quantity: 1
  • best offers: True
  • availability: In Stock
  • options: Ship-to-home

seller cyclemufflermo:

  • city: Denver, Colorado
  • # reviews: 419
  • rating: 100.0%

payments cyclemufflermo:

  • wallet: Google-pay
  • other
  • credit card: Mastercard

returns cyclemufflermo:

  • policy: No Returns

general cyclemufflermo:

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

shipping cyclemufflermo:

  • cost: $0.00
  • type: Fixed
  • transit: 3-9 Days
  • service: Standard
  • class: Standard
for models: yz400, yz400f, for makes: yamaha, for years: 1999-2001, placement on vehicle: exhaust, type: muffler, country of origin: japan,
category: motorcycle parts > motorcycle scooter parts accessories > exhaust emission systems > silencers, mufflers baffles, sku: 15559181113778603,
Yamaha YMS400 Is Similar To:
cyclemufflermo logo
1 offer $149.99 USD
  • Used. Offer #1 priced at $149.99 + $93.68 shipping estimate = $243.67* total. Genuine factory Yamaha exhaust system in good working condition. 2022 Yamaha WR250F.+$93.68 shipping

Copyright © cyclemufflermo.com