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  3. WPS N100.604-102.5

WPS N100.604-102.5 Mikuni Jet

fits model: Ttr125e. make: Yamaha. year: 2003–2009.

N100.604-102.5 Wps Mikuni Main Jet For Yamaha Ttr125e 2003-2009

( Brand: Wps ), ( Manufacturer Part Number: N100.604-102.5 ), ( Part Type: Jet ), ( Country Of Origin: Us ), ( Oe/oem Part Number: N100.604-102.5 4/pk14da-2cc13b ), ( Item Length: 0.400 )

Review WPS Mikuni Main Jet Yamaha fits TTR125E 2003–2009

The **Mikuni N100.604-102.5 jet** is a precision-engineered, high-performance carburetor designed specifically for the Yamaha TTR125E models produced between 2003 and 2009, offering an ideal balance of reliability, throttle response, and fuel efficiency for off-road and trail riding. Crafted from durable materials, this jet features a robust stainless steel body and a high-quality piston assembly, ensuring long-lasting performance even under demanding conditions such as dusty trails, steep climbs, or aggressive riding styles. The **100.604 main jet** and **102.5 pilot jet** combination is meticulously calibrated to deliver optimal fuel-air mixture ratios, providing smooth acceleration, better throttle control, and improved engine efficiency without compromising power or stability. Whether tackling rough terrain, navigating tight corners, or cruising at higher speeds, this carburetor enhances the TTR125E s responsiveness while reducing fuel waste and emissions, making it a standout choice for riders seeking both performance and longevity. Its compatibility with Yamaha s fuel injection system ensures seamless integration, allowing for easy installation with minimal tuning required, while its robust construction resists clogging from dirt and debris, a common issue in off-road applications. Ideal for both stock and modified setups, this Mikuni carburetor is a trusted upgrade for riders who demand precision, durability, and consistent performance from their Yamaha TTR125E.

### Pros and Cons of buying a **N100.604-102.5 Mikuni Jet for Yamaha TTR125E (2003 2009)**

#### **Pros:**

1. **Improved Throttle Response** The Mikuni jet kit is designed to optimize fuel delivery, resulting in a more responsive throttle, especially at low and mid-range RPMs. This can make the TTR125E feel more engaging and easier to control in traffic or during acceleration.

2. **Better Fuel Efficiency** Properly tuned jets can improve combustion efficiency, potentially reducing fuel consumption compared to the stock carburetor setup, which may be slightly outdated or less optimized for modern fuel blends.

3. **Smoother Power Delivery** The stock carburetor on the TTR125E can sometimes exhibit a jerky or uneven powerband, particularly at higher RPMs. The Mikuni jets are known for providing a more linear and consistent power curve, which can make the bike feel more refined.

4. **Compatibility with Modern Fuel** Older carburetors (like the stock Yamaha unit) may struggle with modern fuel formulations (e.g., higher ethanol content). Mikuni jets are often better suited to handle these changes, reducing the risk of running rich or experiencing fuel-related issues.

5. **Easier Maintenance** Mikuni carburetors are generally more straightforward to service and adjust compared to some aftermarket alternatives. The jets are also easier to replace if they become clogged or worn over time.

6. **Enhanced Performance in All Conditions** The Mikuni setup can help the TTR125E perform better in both cold starts and high-altitude conditions, where stock carburetors may struggle with fuel delivery.

7. **Aesthetic Appeal** If you prefer a cleaner look, Mikuni carburetors are often considered more visually appealing than the stock Yamaha unit, especially when paired with a Mikuni air filter or other aftermarket intake components.

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#### **Cons:**

1. **Cost** While not excessively expensive, the Mikuni jet kit (including jets, gaskets, and sometimes an air filter) will add to your budget. For a bike like the TTR125E, which is already a budget-friendly adventure bike, this may be seen as an unnecessary expense if you re not planning to modify much else.

2. **Installation Complexity** If you re not experienced with carburetor work, installing the jets may require some patience. You ll need to adjust the idle mixture screws (H and L) carefully to avoid running too lean or rich, which can cause rough idling, stalling, or even damage to the engine if not done correctly.

3. **Potential for Over-Tuning** If the jets are too aggressive for your riding style or local conditions (e.g., high altitude, cold climates), you might end up with a bike that s harder to start, runs poorly at low RPMs, or even stalls frequently. The stock jets are already tuned for a balance of drivability and performance, so upgrading may require fine-tuning.

4. **Limited Power Gain** The TTR125E is not a high-performance bike to begin with, and the power increase from Mikuni jets will likely be modest (perhaps 2 5 hp at best). If you re looking for significant performance gains, you might need to consider other modifications (e.g., exhaust, clutch, or even a different engine setup).

5. **Ethanol Compatibility Concerns** While Mikuni jets are generally better suited for modern fuel, some riders report that high-ethanol fuels (e.g., E15 or E30) can still cause issues like clogged jets or fuel system problems over time. Regular maintenance (e.g., carburetor cleaning) will be necessary.

6. **No Guarantee of Reliability** Like any aftermarket part, there s a small risk of quality control issues. While Mikuni is a reputable brand, a poorly installed or mismatched jet kit could lead to problems, especially if the bike is already several years old.

7. **May Void Warranty (If Applicable)** If your TTR125E is still under warranty, installing aftermarket carburetor jets could void coverage, especially if the manufacturer considers it a "modification" rather than a maintenance item.

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### **Conclusion:**

The **N100.604-102.5 Mikuni jet kit** is a worthwhile upgrade for the **Yamaha TTR125E (2003 2009)** if you re looking to improve throttle response, fuel efficiency, and overall drivability without committing to major modifications. It s a relatively simple and cost-effective way to modernize the bike s carburetor setup, especially if you re already running other aftermarket components (like an air filter or exhaust).

However, the benefits are incremental, and the modification requires careful tuning to avoid negative side effects. If you re not comfortable adjusting carburetors or don t want to deal with potential fine-tuning issues, the stock setup may suffice for casual riding.

For riders who prioritize **reliability, simplicity, and modest performance gains**, the Mikuni jets are a solid choice. For those seeking **dramatic power increases or a more aggressive setup**, other modifications (e.g., a different carburetor, exhaust, or even a different engine) would be more appropriate.

### **Recommendation:**

- **If you re already modifying the bike** (e.g., adding an aftermarket air filter, exhaust, or suspension upgrades), the Mikuni jets are a logical next step to complement those changes.

- **If you re on a tight budget**, consider starting with simpler upgrades (e.g., a high-quality air filter or exhaust) before investing in carburetor work.

- **If you re not experienced with carburetors**, seek guidance from a mechanic or experienced rider to ensure proper installation and tuning.

- **For best results**, pair the Mikuni jets with a **high-quality fuel** (preferably a premium or synthetic blend) and perform regular maintenance (e.g., carburetor cleaning every 2 3 years).

**Final Verdict:** The Mikuni jet kit is a **good upgrade** for the TTR125E if used correctly, but it s not a game-changer. It s best suited for riders who want a slightly more refined and efficient bike without major modifications.

Details:

Specifications: Brand: Mikuni, MPN: N100.604-102.5 4/PK, OE/OEM Part Number: 4/PK14da-2cc13b, Item length : 0.4 Quantity: Menu Mikuni N100.604-102.5 Main Jet For Yamaha TTR125E 2003 -2009: N100.604 Series Jet: Replacement main jet for fuel system tuning and carburetor service. Features: Genuine Mikuni replacement part. Precision-machined brass construction.

Image Reference Dimensions: Approx. Untitled Document. This is a single unit listing for one jet, ideal maintenance, repair, or jetting adjustments. Sold as 1 individual jet.

N100.604-102.5 main jet specification. Designed for consistent fuel metering and tuning performance.

specifications intakefuelmotorcycle:

  • for models: Ttr125e
  • for makes: Yamaha
  • for years: 2003-2009
  • brand: Wps
  • mpn: N100.604-102.5
  • part type: Jet
  • country of origin: Us
  • oe/oem part number: N100.604-102.5 4/pk14da-2cc13b
  • item length: 0.400

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for models: ttr125e, for makes: yamaha, for years: 2003-2009, part type: jet, country of origin: us, oe/oem part number: n100.604-102.5 4/pk14da-2cc13b, item length: 0.400,
category: motorcycle parts > motorcycle scooter parts accessories > air intake fuel delivery, sku: 23339704441980723,
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