Suzuki Rf 900 Common Problems

The Suzuki RF900, a sport-touring motorcycle produced from 1994 to 1999 (with some regional variations in production years), holds a special place in the hearts of many riders. Known for its powerful engine, comfortable riding position, and distinctive styling, it provided a compelling alternative to more focused sportbikes of the era. However, like any motorcycle, the RF900 has its share of common problems that potential buyers and current owners should be aware of. Knowing these issues ahead of time can help you make informed decisions, perform preventative maintenance, and keep your RF900 running smoothly for years to come.

Is My RF900 Gonna Leave Me Stranded? Understanding Potential Engine Woes

The heart of the RF900 is its liquid-cooled, inline-four engine, derived from the GSX-R750. While generally robust, several potential issues can crop up over time, especially given the age of most RF900s on the road today.

Cam Chain Tensioner (CCT) Failure: This is arguably the most well-known problem. The original CCT is a mechanical unit that can fail, leading to excessive cam chain noise and, in severe cases, engine damage. Symptoms include a rattling or ticking sound, especially at idle or low RPMs. Replacing the original CCT with a manual or updated aftermarket unit is highly recommended. Many riders opt for a manual CCT as it offers greater control and eliminates the risk of automatic failure.
Carburetor Issues: The RF900 uses a bank of four Mikuni carburetors. Over time, these can become gummed up with old fuel, leading to poor running, hesitation, and difficulty starting. Regular carburetor cleaning and synchronization are essential for optimal performance. Pay close attention to the pilot jets, as these are particularly prone to clogging. Also, check the condition of the rubber diaphragms, as they can crack and leak, causing running problems.
Fuel Pump Reliability: The fuel pump, while not a constant source of problems, can fail due to age and corrosion. If your RF900 is experiencing intermittent stalling or difficulty starting, especially when the fuel tank is low, the fuel pump should be investigated. Consider replacing the fuel pump with a new or refurbished unit.
Overheating: While the RF900 is liquid-cooled, overheating can still occur, particularly in hot weather or during stop-and-go traffic. Check the coolant level, radiator condition, and thermostat function. A faulty thermostat or a clogged radiator can significantly reduce cooling efficiency. Ensure the cooling fan is operating correctly.
Valve Adjustment: Regular valve adjustments are crucial for maintaining engine performance and preventing damage. Follow the manufacturer's recommended service intervals for valve adjustments. Neglecting this can lead to decreased power, increased engine noise, and, in extreme cases, valve damage.

Suspension and Handling: Keeping Your RF900 Planted

The RF900's suspension, while adequate for its time, can feel dated by modern standards. Addressing these common problems can significantly improve handling and ride quality.

Fork Seals: Leaking fork seals are a common issue on older motorcycles, and the RF900 is no exception. Leaking fork seals will result in reduced damping and a messy front end. Replacing the fork seals is a relatively straightforward repair that can dramatically improve handling. Consider upgrading the fork oil with a higher viscosity oil for improved damping performance.
Rear Shock Absorber: The original rear shock absorber is often worn out on RF900s. This can lead to a bouncy ride, poor handling, and reduced cornering stability. Replacing the rear shock with an aftermarket unit is a worthwhile upgrade. Options range from basic replacements to fully adjustable shocks that allow you to fine-tune the suspension to your riding style.
Swingarm Bearings: Check the swingarm bearings for play or stiffness. Worn swingarm bearings can negatively impact handling and stability, especially at higher speeds. Replacing the swingarm bearings can restore a more solid and predictable feel to the rear end.
Steering Head Bearings: Similar to the swingarm bearings, the steering head bearings can wear out over time. This can manifest as a vague feeling in the front end, difficulty holding a line in corners, or a clunking noise when braking. Replacing the steering head bearings can significantly improve steering precision and stability.

Electrical Gremlins: Chasing Down Those Pesky Shorts

Older motorcycles are often susceptible to electrical problems due to aging wiring and components. The RF900 is no exception.

Charging System Issues: The charging system, consisting of the stator, regulator/rectifier, and battery, can be a source of problems. A failing stator or regulator/rectifier can lead to a dead battery and prevent the bike from starting. Regularly check the charging voltage to ensure the system is functioning correctly. Consider upgrading to a MOSFET-type regulator/rectifier, which is more reliable than the original shunt-type unit.
Wiring Harness Problems: Over time, the wiring harness can become brittle and corroded, leading to shorts and intermittent electrical problems. Pay particular attention to connectors and areas where the wiring harness is exposed to the elements. Inspect the wiring harness for any signs of damage and repair or replace as needed. Use dielectric grease on all connectors to prevent corrosion.
Starter Motor: The starter motor can fail due to wear and tear. If your RF900 is having difficulty starting, the starter motor should be inspected. Consider replacing the starter motor brushes or the entire unit if necessary.

Bodywork and Aesthetics: Keeping It Looking Sharp

While the RF900 is known for its stylish design, the bodywork can be prone to certain issues.

Cracked Fairings: The fairings, especially around mounting points, can crack due to age and vibration. Repairing cracked fairings is possible, but may require specialized tools and materials. Consider reinforcing the fairings around mounting points to prevent future cracking.
Faded Paint: The paint on older RF900s can fade due to exposure to the sun and elements. Regular waxing and polishing can help protect the paint and maintain its luster.
Seat Condition: The seat can become cracked and worn over time. Replacing or reupholstering the seat can improve comfort and aesthetics.

Brakes: Stopping Power Concerns

The brakes on the RF900, while adequate when new, can suffer from age-related issues.

Sticking Calipers: The brake calipers can become corroded and sticky, leading to reduced braking performance and uneven pad wear. Regularly clean and lubricate the brake calipers to prevent sticking. Consider rebuilding the calipers with new seals and pistons if necessary.
Brake Lines: The original rubber brake lines can deteriorate over time, leading to a spongy brake feel. Replacing the rubber brake lines with stainless steel braided lines will improve braking performance and provide a more consistent feel.
Master Cylinder: The brake master cylinder can develop leaks or become inefficient due to wear. Rebuilding or replacing the master cylinder can restore proper braking performance.

Frequently Asked Questions

Why is my RF900 cam chain so noisy? The original Cam Chain Tensioner (CCT) is prone to failure. Replacing it with a manual or updated aftermarket unit is highly recommended.
My RF900 is hard to start. What could be the problem? Possible causes include dirty carburetors, a weak fuel pump, or a failing starter motor. Inspect each of these components to diagnose the issue.
The front end feels vague. What should I check? Worn fork seals or steering head bearings are common culprits. Replacing these components can significantly improve steering precision.
My battery keeps dying. What's going on? A failing stator or regulator/rectifier could be the cause. Test the charging system to identify the faulty component.
Where can I find parts for my RF900? Online retailers specializing in motorcycle parts, such as eBay, CMSNL, and Partzilla, are good sources. Also, check with local motorcycle salvage yards.

Conclusion

The Suzuki RF900 is a fantastic motorcycle that offers a blend of performance and comfort. Understanding these common problems and addressing them proactively will ensure your RF900 provides many more miles of enjoyable riding. Regular maintenance and careful attention to detail are key to keeping this classic machine on the road.