The Yamaha MT-15, a streetfighter known for its aggressive styling and nimble handling, has captured the hearts of many riders, especially in the Asian market. However, like any motorcycle, it's not without its quirks. While the MT-15 offers a thrilling riding experience, potential buyers and current owners should be aware of some common issues that have been reported over time. Understanding these potential problems can help you make an informed decision or address issues more effectively.

Is the Yamaha MT-15 really worth the hype? Let's dive into the issues.

Common Gripes: What MT-15 Owners are Talking About

The MT-15, while undoubtedly fun, isn't perfect. Several recurring issues have been brought up by owners across various forums and reviews. These range from minor annoyances to potentially more significant mechanical concerns. Let's break them down:

  • Stiff Suspension: A common complaint revolves around the MT-15's suspension setup, particularly the rear monoshock. Many riders find it to be excessively stiff, especially on less-than-perfect road surfaces. This can lead to a jarring and uncomfortable ride, especially on longer journeys. While a stiffer suspension can improve handling on smooth roads and during aggressive riding, it compromises comfort for everyday use. The stiffness can be amplified by the relatively light weight of the motorcycle, making bumps and potholes feel more pronounced.

  • Engine Stalling Issues: Some MT-15 owners have reported instances of engine stalling, particularly at low speeds or when coming to a stop. This can be frustrating and even dangerous, especially in heavy traffic. The causes of stalling can be varied, ranging from issues with the fuel injection system to problems with the idle speed setting. Faulty sensors or even contaminated fuel can also contribute to stalling problems.

  • Chain Noise and Wear: The drive chain on the MT-15 seems to be prone to excessive noise and wear, requiring frequent lubrication and adjustment. This can be due to several factors, including the quality of the chain itself, the riding conditions, and the rider's maintenance habits. Aggressive acceleration and riding in dusty or muddy environments can accelerate chain wear. Neglecting regular cleaning and lubrication will also shorten the chain's lifespan.

  • Headlight Performance: While the MT-15 boasts a stylish LED headlight, some riders find its performance to be lacking, especially during night rides. The throw and spread of the light might not be sufficient for optimal visibility, particularly at higher speeds. This can be a safety concern, especially on poorly lit roads. The issue is often exacerbated by the headlight's design, which prioritizes aesthetics over functionality.

  • Build Quality Concerns: While generally well-built, some owners have reported minor issues with the MT-15's build quality, such as rattling panels, loose fasteners, and paint chipping. These issues are often cosmetic but can be irritating for owners who expect a higher level of fit and finish. The issues are more common on earlier models and may have been addressed in later iterations.

Digging Deeper: Exploring the Root Causes

Understanding the "what" is important, but knowing the "why" is even better. Let's delve into the potential root causes of some of these common MT-15 problems:

  • Suspension Stiffness: A Design Trade-off: The stiff suspension is likely a deliberate design choice by Yamaha to enhance the MT-15's sporty handling characteristics. A stiffer suspension allows for more precise control and reduces body roll during cornering. However, this comes at the expense of ride comfort. The MT-15 is positioned as a performance-oriented motorcycle, and the suspension reflects this focus. The relatively short wheelbase of the MT-15 can also contribute to the perceived stiffness, as it makes the ride more sensitive to road imperfections.

  • Engine Stalling: Fueling and Sensor Issues: Engine stalling can be a complex issue with multiple potential causes. One possibility is a problem with the fuel injection system, such as a faulty injector or a malfunctioning fuel pump. Another potential cause is a problem with the idle speed setting, which may be too low. Sensors, such as the throttle position sensor (TPS) or the crankshaft position sensor (CPS), can also fail and cause the engine to stall. Additionally, issues with the evaporative emission control system (EVAP) can lead to stalling.

  • Chain Noise and Wear: Material and Maintenance: The chain noise and wear issues could be related to the quality of the chain itself. Some aftermarket chains are known to be more durable and quieter than the stock chain. However, proper maintenance is also crucial. Regularly cleaning and lubricating the chain with a good quality chain lubricant can significantly extend its lifespan and reduce noise. Adjusting the chain tension according to the manufacturer's specifications is also essential.

  • Headlight Performance: Design vs. Functionality: The MT-15's headlight design prioritizes aesthetics over pure functionality. The small size and shape of the headlight may limit its ability to project a bright and wide beam of light. While LED headlights are generally more efficient and brighter than traditional halogen headlights, their performance can still vary depending on the design and quality of the optics.

  • Build Quality: Cost Optimization: Minor build quality issues, such as rattling panels and loose fasteners, are often a result of cost optimization measures during manufacturing. While Yamaha is known for its overall quality, some compromises may have been made to keep the MT-15's price competitive. These issues are typically cosmetic and do not affect the motorcycle's performance or reliability.

Troubleshooting and Solutions: What You Can Do

So, you're facing one of these issues? Don't panic! Here are some potential solutions you can try:

  • Stiff Suspension:

    • Adjust the preload: If your MT-15 has adjustable preload on the rear shock, try reducing it to soften the ride.
    • Consider an aftermarket shock: Replacing the stock shock with an aftermarket unit designed for comfort can significantly improve the ride quality. Options from brands like Ohlins, YSS, and Nitron are available.
    • Lower tire pressure (slightly): Reducing tire pressure by a small amount (within the manufacturer's recommended range) can improve comfort, but be careful not to go too low, as this can affect handling and tire wear.

  • Engine Stalling:

    • Check the fuel: Ensure you're using good quality fuel and that there's no water or debris in the tank.
    • Inspect the spark plug: A fouled or worn spark plug can cause stalling. Replace it if necessary.
    • Clean the fuel injectors: Clogged fuel injectors can restrict fuel flow and cause stalling. Consider using a fuel injector cleaner additive or having them professionally cleaned.
    • Consult a mechanic: If the stalling persists, it's best to take the bike to a qualified mechanic to diagnose the underlying cause and perform any necessary repairs.

  • Chain Noise and Wear:

    • Clean and lubricate the chain regularly: Use a good quality chain cleaner and lubricant.
    • Adjust the chain tension: Ensure the chain tension is within the manufacturer's specifications.
    • Consider an aftermarket chain: If the stock chain is wearing prematurely, consider replacing it with a more durable aftermarket chain.

  • Headlight Performance:

    • Adjust the headlight beam: Ensure the headlight beam is properly aimed.
    • Consider auxiliary lights: Adding auxiliary lights, such as fog lights or driving lights, can significantly improve visibility.
    • Upgrade the headlight bulb (if possible): If your MT-15 uses a replaceable headlight bulb, consider upgrading to a brighter bulb.

  • Build Quality:

    • Tighten loose fasteners: Regularly check and tighten any loose fasteners.
    • Use thread locker: Applying thread locker to fasteners can help prevent them from loosening over time.
    • Address rattling panels: Use foam tape or rubber shims to dampen vibrations and reduce rattling.

Preventative Measures: Staying Ahead of the Curve

Prevention is always better than cure. Here are some tips to help you avoid common MT-15 problems:

  • Regular Maintenance: Follow the manufacturer's recommended maintenance schedule. This includes regular oil changes, filter replacements, and chain maintenance.
  • Proper Riding Habits: Avoid aggressive acceleration and braking, as this can put extra stress on the engine and drivetrain.
  • Quality Fuel and Lubricants: Use good quality fuel and lubricants that meet the manufacturer's specifications.
  • Proper Storage: If you're storing your MT-15 for an extended period, take steps to protect it from the elements and prevent corrosion.
  • Early Detection: Pay attention to any unusual noises or vibrations and address them promptly.

Frequently Asked Questions

  • Is the MT-15 reliable? The MT-15 is generally considered reliable, but it's not without its quirks. Regular maintenance and addressing issues promptly can help ensure its long-term reliability.

  • Is the suspension too stiff for everyday riding? Many riders find the suspension too stiff for everyday riding, especially on rough roads. Consider adjusting the preload or upgrading to an aftermarket shock for improved comfort.

  • What causes the engine to stall? Engine stalling can be caused by various factors, including fuel issues, sensor problems, or idle speed settings. Consulting a mechanic is recommended for accurate diagnosis.

  • How often should I lubricate the chain? Lubricate the chain every 300-500 miles, or more frequently if riding in dusty or wet conditions. Use a good quality chain lubricant for optimal performance.

  • Is the headlight bright enough for night riding? Some riders find the headlight lacking in brightness for night riding. Consider adjusting the beam or adding auxiliary lights for improved visibility.

Conclusion: Making an Informed Choice

The Yamaha MT-15 is a fun and stylish motorcycle that offers a thrilling riding experience. While it has some common issues, these are generally manageable with proper maintenance and preventative measures. By being aware of these potential problems and taking steps to address them, you can enjoy your MT-15 for many years to come. Consider your riding style and needs, and weigh the pros and cons before making a purchase or investing in modifications to address the mentioned issues.