The Yamaha RXG, a name that still evokes a certain nostalgia among Indian motorcycle enthusiasts, was a sporty and powerful machine in its heyday. However, like any classic, the RXG has its share of quirks and potential problems that owners, both past and present, need to be aware of. Understanding these issues can help you troubleshoot, maintain, and ultimately enjoy the ride for years to come.

The All-Too-Common Carburetor Conundrum

One of the most frequent complaints leveled against the RXG, and indeed many older two-stroke motorcycles, revolves around the carburetor. This crucial component is responsible for mixing air and fuel in the correct ratio for optimal combustion. Over time, the carburetor can become clogged with dirt and debris, leading to a variety of issues.

  • Starting Problems: A dirty or improperly adjusted carburetor can make starting the RXG a real pain, especially in cold weather.
  • Poor Idling: The engine might idle roughly, stall frequently, or idle too high.
  • Hesitation or Stuttering: When accelerating, the engine might hesitate or stutter, indicating an incorrect air/fuel mixture.
  • Reduced Fuel Efficiency: A rich mixture (too much fuel) will significantly decrease your mileage.

The Fix: Regular cleaning and maintenance of the carburetor are essential. This involves disassembling the carburetor, cleaning all jets and passages with carburetor cleaner, and reassembling it carefully. You might also need to adjust the air/fuel mixture screw to fine-tune the engine's performance. If the carburetor is severely damaged or worn, replacement might be necessary.

The Oiling System: A Two-Stroke's Lifeline

The Yamaha RXG, being a two-stroke engine, relies on a crucial oiling system to lubricate the engine's internal components. Unlike four-stroke engines, two-strokes don't have an oil sump; instead, oil is mixed with the fuel or injected directly into the engine. Problems with this system can lead to catastrophic engine damage.

  • Oil Pump Failure: The oil pump can fail due to wear and tear or clogging, resulting in insufficient lubrication. This is a serious issue that can cause the piston to seize in the cylinder, leading to major engine damage.
  • Clogged Oil Lines: The oil lines can become clogged with old oil or debris, restricting oil flow to the engine.
  • Incorrect Oil Mixture: If you're manually mixing oil with the fuel (pre-mixing), using the wrong oil ratio can be detrimental. Too little oil, and you risk engine seizure; too much oil, and you'll experience excessive smoke and poor performance.

The Fix: Regularly inspect the oil pump and oil lines for any signs of leaks or damage. Ensure you're using the correct two-stroke oil and mixing it at the recommended ratio (usually around 2-3% for pre-mix systems). If you suspect the oil pump is failing, have it inspected and repaired or replaced by a qualified mechanic. Some owners prefer to convert to a pre-mix system for simplicity and reliability, but this requires careful attention to the oil ratio.

Ignition Issues: Sparking the Trouble

The ignition system is responsible for generating the spark that ignites the air/fuel mixture in the cylinder. Problems with the ignition system can prevent the engine from starting or cause it to run poorly.

  • Faulty Spark Plug: A worn or fouled spark plug is a common culprit.
  • Weak Ignition Coil: The ignition coil can weaken over time, resulting in a weak spark.
  • Problems with the CDI Unit: The Capacitor Discharge Ignition (CDI) unit controls the timing of the spark. A faulty CDI unit can cause the engine to misfire or not start at all.
  • Wiring Issues: Damaged or corroded wiring can disrupt the flow of electricity to the ignition components.

The Fix: Start by checking the spark plug. Clean it, gap it correctly, or replace it if necessary. If the problem persists, test the ignition coil and CDI unit. Use a multimeter to check the resistance of the coil. If the CDI unit is suspected, it's best to have it tested by a professional. Inspect all wiring connections for corrosion or damage and repair or replace them as needed.

Suspension Woes: A Bumpy Ride

The suspension system plays a vital role in providing a comfortable and stable ride. Over time, the suspension components of the RXG can wear out, leading to a less-than-ideal riding experience.

  • Worn Fork Seals: The fork seals can leak, causing the front suspension to become soft and ineffective.
  • Weak or Sagging Rear Shocks: The rear shocks can lose their damping ability, resulting in a bouncy ride and poor handling.
  • Loose or Worn Suspension Bushings: The bushings in the suspension linkages can wear out, causing play and instability.

The Fix: Regularly inspect the fork seals for leaks. If they're leaking, replace them as soon as possible. Rebuilding the front forks with new seals and oil is a relatively straightforward procedure. For the rear suspension, consider replacing the shocks with new units or having them rebuilt by a specialist. Inspect the suspension bushings for wear and replace them as needed.

Electrical Gremlins: A Shocking Experience

Like many older motorcycles, the Yamaha RXG can suffer from electrical problems due to corrosion, damaged wiring, and failing components.

  • Battery Issues: The battery can fail due to age or improper charging.
  • Faulty Wiring: Damaged or corroded wiring can cause shorts, open circuits, and other electrical problems.
  • Problems with Lights and Indicators: The lights and indicators might stop working due to blown bulbs, faulty switches, or wiring issues.
  • Charging System Problems: The charging system might fail to charge the battery, leading to a dead battery and starting problems.

The Fix: Regularly check the battery voltage and charging system output. Replace the battery if it's no longer holding a charge. Inspect all wiring connections for corrosion and repair or replace them as needed. Use a multimeter to troubleshoot electrical problems. If you're not comfortable working with electrical systems, seek the help of a qualified mechanic.

The Exhaust System: More Than Just Noise

The exhaust system plays a crucial role in engine performance and emissions. Problems with the exhaust system can affect the RXG's power output and fuel efficiency.

  • Clogged Exhaust Ports: Carbon buildup in the exhaust ports can restrict exhaust flow, reducing engine power.
  • Leaky Exhaust System: Leaks in the exhaust system can cause a loss of power and increase noise levels.
  • Damaged Exhaust Pipe: The exhaust pipe can be damaged by rust or impacts, affecting its performance.

The Fix: Regularly clean the exhaust ports to remove carbon buildup. Inspect the exhaust system for leaks and repair them as needed. Replace any damaged sections of the exhaust pipe. Consider upgrading to an aftermarket exhaust system for improved performance (but be mindful of local noise regulations).

Brakes: The Crucial Stopping Power

While often overlooked, a properly functioning braking system is paramount for safety. The RXG's braking system, typically consisting of drum brakes, requires regular maintenance to ensure optimal performance.

  • Worn Brake Shoes: The brake shoes can wear down over time, reducing braking effectiveness.
  • Contaminated Brake Drums: The brake drums can become contaminated with oil or grease, reducing braking power.
  • Sticking Brake Cables: The brake cables can become stiff and sticky, making it difficult to apply the brakes smoothly.

The Fix: Regularly inspect the brake shoes for wear and replace them as needed. Clean the brake drums with brake cleaner to remove any contaminants. Lubricate the brake cables to ensure smooth operation. If you're not comfortable working on brakes, seek the help of a qualified mechanic.

Frequently Asked Questions

  • Why is my RXG hard to start? A dirty carburetor, weak spark plug, or low battery are common causes. Clean the carburetor, replace the spark plug, and check the battery voltage.
  • My RXG is smoking a lot. What could be wrong? This could be due to an overly rich air/fuel mixture, too much oil in the pre-mix, or worn piston rings. Adjust the carburetor, check the oil ratio, and inspect the piston rings.
  • How often should I clean the carburetor? It depends on usage and environmental conditions, but generally, cleaning every 6 months to a year is recommended. More frequent cleaning may be necessary if you ride in dusty conditions.
  • What type of oil should I use for my RXG? Use a high-quality two-stroke oil specifically designed for air-cooled engines. Refer to your owner's manual for the recommended oil type and mixing ratio.
  • My RXG's battery keeps dying. What's the problem? This could be due to a faulty battery, a problem with the charging system, or a parasitic drain. Test the battery and charging system, and check for any wiring issues causing a drain.

Conclusion

The Yamaha RXG, while a classic, requires diligent maintenance to keep it running smoothly. By understanding the common problems and their solutions, you can ensure that your RXG continues to provide you with years of riding enjoyment. Regular maintenance is key to preventing major issues and keeping your RXG on the road.