Among the many symbols of classic two-stroke performance, few components define the Yamaha RD series as completely as the Escapamento RD the exhaust system that gives these motorcycles their distinctive power delivery and sound. More than a functional part, the RD exhaust is an engineering statement of resonance, precision, and balance, shaping how fuel, air, and combustion energy flow through the heart of Yamaha’s legendary two-stroke engines.
For riders restoring vintage models like the RD125, RD135, or RD350, the Escapamento RD is both a technical necessity and a piece of heritage. A well-designed exhaust transforms the motorcycle’s performance, enhances throttle response, and recreates the unmistakable high-pitched wail that defines the RD lineage. Meanwhile, modern fabricators have reimagined this system with advanced materials, improved chamber geometry, and superior craftsmanship offering enthusiasts the perfect blend of authenticity and performance.
This comprehensive guide explores every aspect of the Escapamento RD: its role in two-stroke performance, types and materials, installation process, compatibility, maintenance, and even future innovations in exhaust technology. Whether you’re restoring an original RD to pristine condition or optimizing a track-ready build, this resource will help you make the most of every pulse, curve, and resonance of your Yamaha’s exhaust system..
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What is an Escapamento RD and Why It Matters
An Escapamento RD refers to a high-performance or replacement exhaust system designed specifically for the Yamaha RD series of two-stroke motorcycles. More than a simple component, it’s a performance-critical part that influences how efficiently the engine expels exhaust gases, defines the iconic RD sound, and determines how much power the bike produces.
Built for models like the RD125, RD135, and RD350, this exhaust system is engineered to match the flow characteristics and resonance needs of two-stroke engines. Its design can dramatically alter throttle response, torque delivery, and sound frequency.
The Escapamento RD also plays a vital role in restoration projects and custom builds, as original Yamaha RD exhausts are often hard to find or corroded after decades of use. Enthusiasts seek these aftermarket systems for their blend of authenticity and improved performance tuning potential.
Why Replace the Stock Yamaha RD Exhaust with an Escapamento RD
Replacing a stock exhaust on an RD isn’t just about aesthetics it’s a strategic upgrade to reclaim lost horsepower and efficiency. The OEM exhausts were tuned for emissions and noise restrictions of their time, limiting the full potential of the RD’s two-stroke engine. An aftermarket Escapamento RD unlocks this latent power by optimizing gas flow and resonance timing.
When upgrading, riders typically seek better throttle response, a sharper powerband, and that signature crisp two-stroke scream. High-quality RD exhausts reduce unwanted backpressure, improving scavenging and enabling better cylinder filling during each cycle.
From a restoration standpoint, a new exhaust can transform a neglected RD into a roadworthy classic. Modern Escapamento RD systems often feature corrosion-resistant materials and precision welding, ensuring both performance and longevity qualities the original mild-steel systems often lacked.
What Are the Main Types of Escapamento RD Available
Aftermarket Escapamento RD systems come in multiple styles and configurations, each with distinct properties affecting performance, weight, and durability.
The primary distinction lies between handcrafted performance exhausts, often made by specialized fabricators in Brazil or Europe, and mass-produced replacement systems that mimic factory dimensions. Performance units generally include tuned expansion chambers for precise resonance, while basic replacements focus on fitment and sound authenticity.
Stainless Steel vs Carbon Steel Exhausts
Stainless steel (AISI 304 or 316) exhausts resist corrosion and maintain their finish over time. They’re ideal for daily riders and coastal regions where humidity is high. Their density slightly alters acoustic tone, giving a sharper, higher-pitched sound.
Carbon steel, used in many traditional RD pipes, is lighter and offers a more classic appearance. It tends to enhance mid-range resonance but requires regular maintenance or high-temperature paint to prevent rust. Some tuners prefer carbon steel for its authentic look and warm tone reminiscent of 1980s factory racing exhausts.
| Material Type | Durability | Sound Profile | Weight | Maintenance |
|---|---|---|---|---|
| Stainless Steel | Very High | Crisp, bright tone | Slightly heavier | Low |
| Carbon Steel | Moderate | Warm, classic tone | Lighter | Requires painting/oiling |
Gomo Curve vs Smooth Curve: What’s the Difference
The curve geometry of the exhaust determines how exhaust gases resonate and reflect within the expansion chamber.
Gomo curve (segmented or “gomo” design) uses multiple welded cone sections, creating a distinctive stepped look. This style enhances the exhaust’s ability to reflect pressure waves efficiently, improving powerband precision ideal for racing or tuned engines.
Smooth curve designs, on the other hand, have continuous bends that favor aesthetics and smoother gas flow. They produce a slightly broader but softer power curve, better suited for everyday street riding or restoration authenticity.
Each curve type interacts with exhaust volume, cone angle, and diffuser length to define where torque and horsepower peak critical variables in two-stroke tuning.
How to Properly Install an Escapamento RD
Installing an Escapamento RD is a straightforward task for experienced mechanics but requires precision to ensure performance gains and prevent leaks or misalignment.
A correct installation not only secures the exhaust mechanically but also aligns it with the engine’s exhaust port geometry and mounting brackets, ensuring optimal flow dynamics.
Required Tools and Workspace
Before starting, gather essential tools:
- Socket set and torque wrench
- Gasket sealant and new copper exhaust gasket
- Rubber mallet
- High-temp anti-seize compound
- Motorcycle paddock stand
- Safety gloves and eye protection
Ensure a clean, level workspace. Two-stroke exhausts rely on precise alignment any tilt or gap may create resonance loss or leaks, reducing performance.
Step-by-Step Installation Guide
- Remove the old exhaust: Allow the bike to cool, disconnect the silencer and header bolts, and carefully lower the pipe.
- Clean the exhaust port: Remove carbon buildup and residue to ensure a perfect seal.
- Install the new gasket: Apply a thin layer of high-temp sealant and insert the new copper gasket.
- Align the new Escapamento RD: Position the expansion chamber, loosely tighten bolts to allow adjustment.
- Secure mounting points: Once aligned, torque all bolts to factory specs.
- Attach the silencer and springs: Ensure tensioned fit and no vibration contact with frame parts.
Post-Install Tuning and Checks
After installation, inspect for leaks by feeling for air pulses around the joints while the engine idles. Perform a short test ride to evaluate sound and throttle response.
You may need to re-jet the carburetor a richer main jet prevents lean running due to improved airflow. Check spark plug color and adjust as needed. Final tuning ensures you extract full performance without engine risk.
How Escapamento RD Affects Performance and Sound
The Escapamento RD directly influences how the Yamaha RD’s powerband behaves. Two-stroke engines rely on exhaust resonance to “push back” unburned fuel-air mixture into the cylinder before the next combustion cycle a process known as scavenging.
A properly tuned RD exhaust sharpens mid-to-top-end power, adding 10–15% horsepower gains depending on model and setup. For instance, a well-matched pipe on an RD135 can boost output from 14 hp to nearly 16 hp, while a RD350 YPVS setup may exceed 45 hp with proper tuning.
Sound-wise, the Escapamento RD defines the character of the motorcycle. Stainless-steel systems produce a crisp “crackling” note, while carbon-steel and mild-steel pipes generate deeper resonance. Adding a silencer core or baffle can adjust decibel levels for street legality.
Pros and Cons of Escapamento RD
| Pros | Cons |
|---|---|
| Significant power and torque gains | May require carburetor retuning |
| Enhanced sound and aesthetics | Can increase noise levels |
| Better throttle response | Some models not road legal |
| Corrosion-resistant options available | High-quality units can be expensive |
| Authentic for restoration projects | Needs periodic cleaning and inspection |
The overall advantage lies in its performance-per-dollar value, especially for riders passionate about two-stroke tuning. Properly chosen and installed, it delivers measurable mechanical and sensory improvements.
How to Choose the Right Escapamento RD for Your Yamaha Model
Choosing the correct Escapamento RD depends on your bike model, intended use, and budget. Exhaust port diameters, mounting brackets, and chamber length vary significantly across RD generations.
Compatibility by RD Model (RD125, RD135, RD350)
- RD125: Lightweight systems favor low-to-mid RPM performance. Ideal for city commuting or mild tuning.
- RD135: Offers balanced torque and top-end. Choose gomo curve pipes for sportier response.
- RD350: Requires dual expansion chambers. Prioritize resonance-matched designs and durable materials due to high heat output.
Compatibility tables from manufacturers often list models and corresponding exhaust types. Always verify flange angles and bracket positions before purchase.
Daily Use vs Racing vs Restoration Projects
For daily use, stainless or mild-steel smooth-curve exhausts provide reliability and acceptable noise levels.
For racing or track, lightweight gomo-style chambers maximize high-RPM power.
For restoration, period-correct replicas maintain authenticity while offering improved metallurgy and finish.
Where to Buy Escapamento RD and What Price Range to Expect
The Escapamento RD market is vibrant, especially in Brazil and Europe where Yamaha RD models remain popular.
- Local Fabricators (Brazil, Portugal, Spain): Custom-made gomo exhausts range from R$1,000–R$2,500.
- Online Retailers and Marketplaces: Sites like Mercado Livre, OLX, or eBay offer new and used options between $150–$400 USD.
- Performance Brands: Recognized fabricators such as Pro Tork, Vini Racing, or Roncar specialize in RD systems.
When purchasing internationally, factor in shipping costs, customs duties, and regional emission laws. Avoid low-cost copies made with thin-gauge metal they often crack or lose performance over time.
What Maintenance and Legal Considerations Should You Know
Regular maintenance preserves both performance and longevity. Clean the internal chamber periodically with degreaser or kerosene to remove carbon buildup. For carbon-steel units, apply anti-rust coating every few months.
Legally, noise and emissions are governed by CONAMA Resolution 418/2009 (Brazil) and equivalent EU standards. Some racing exhausts exceed decibel limits for street use check local inspection requirements to avoid fines or confiscation. Adding a removable silencer core often brings noise within legal range.
Common Myths About Escapamento RD and Real Facts
| Myth | Fact |
|---|---|
| All aftermarket exhausts add horsepower | Only tuned expansion chambers properly matched to the engine yield real gains |
| Carbon steel pipes are outdated | Many tuners still prefer them for authentic tone and lightweight performance |
| Louder exhaust means more power | Noise doesn’t equal efficiency; resonance tuning is what matters |
| RD135 exhausts fit RD125 | Flange angle and port diameter differ, causing performance loss or leaks |
| Re-jetting isn’t necessary | Always re-tune carburetion after increasing exhaust flow |
Understanding these truths ensures informed upgrades and long-term reliability.
What Are Future Trends in Two-Stroke Motorcycle Exhausts
While classic RD models belong to a bygone era of analog motorcycling, modern fabrication keeps pushing performance boundaries.
Expect to see CNC-rolled cones, hydroformed expansion chambers, and modular silencers offering tunable resonance. Eco-conscious enthusiasts are also exploring synthetic oils and cleaner combustion to keep vintage two-strokes street legal.
Digital modeling via CFD (Computational Fluid Dynamics) is revolutionizing exhaust design, enabling perfect pressure wave mapping before fabrication. The next generation of Escapamento RD may combine heritage aesthetics with data-driven efficiency.
Conclusion
The Escapamento RD stands as more than a replacement part it’s the heartbeat of Yamaha’s iconic two-stroke heritage. Whether restoring an RD350 to factory glory or extracting the last ounce of performance from an RD135, the exhaust defines how your machine breathes, sounds, and accelerates.
By choosing the right material, curve design, and fitment, riders can revive the unmistakable thrill of the RD series while preserving mechanical precision and style. With proper installation and maintenance, an Escapamento RD delivers both nostalgia and performance that endure for decades. For more informative articles related to Auto’s you can visit Auto Category of our Blog.
FAQ’s
Depending on model and tuning, expect 5–15% increases in horsepower, sharper throttle response, and broader mid-range power.
No. Each model (RD125, RD135, RD350) has unique port and bracket geometries. Always verify compatibility before purchase.
Yes. Increased exhaust flow usually requires richer fuel mixtures to maintain proper combustion and avoid lean running.
Noise levels range from 88–100 dB depending on pipe design and silencer type. A removable baffle can reduce sound for street legality.
Street legality depends on local noise and emission laws. In Brazil, only systems within CONAMA limits are approved for road use.
Gomo curves use segmented cones for sharper resonance and racing performance, while smooth curves prioritize aesthetics and a wider torque band.
Clean every 2,000–3,000 km, especially if running rich mixtures. Inspect welds and joints regularly for cracks or carbon leaks.
Skilled enthusiasts can install it with basic tools and patience. For tuning or re-jetting, professional assistance is recommended.
