Choosing the right escapamento RD 135 (exhaust system) is more than just a cosmetic upgrade; for enthusiasts of the legendary Yamaha “Black Widow” or the RD 135Z, it is the single most important factor in determining the bike’s performance, power delivery, and that unmistakable two-stroke soul.
In 2026, the market for 2-stroke performance parts has evolved, blending artisanal craftsmanship with modern materials like 304 stainless steel. Whether you are looking for a deep “Dore” growl or a high-revving “dimensionado” for the track, this guide covers everything you need to know.
The Role of the Expansion Chamber in 2-Stroke Performance
Unlike four-stroke engines where the exhaust mainly carries gases away, a two-stroke engine relies on the expansion chamber (the “belly” of the pipe) to function correctly.
A well-designed escapamento dimensionado uses sound waves to “push” unburnt fuel back into the cylinder. This creates a “supercharging” effect at specific RPMs. When choosing your RD 135 exhaust, you must decide where you want that power boost:
- Low to Mid-Range (Média Baixa): Best for city riding and daily commutes.1 It provides torque early on, so you don’t have to constantly redline the bike to move.
- Mid to High-Range (Média Alta): Designed for those who love the “power valve” feel. The bike may feel “sleepy” at low speeds but explodes with power once it hits the power band.
If you are upgrading your bike’s performance, it is also a good time to review your overall road readiness, including do you need a drivers license for a scooter or small motorcycle in your specific region.
Top Escapamento RD 135 Brands for 2026
The Brazilian and international markets offer several iconic brands that have perfected the RD 135’s “berro” (scream).
1. Dore Escapamentos
Known as the “Gold Standard” for RD enthusiasts. Dore exhausts are famous for their high-quality welds and a sound profile that is loud, crisp, and aggressive.
- Best for: Pure performance and “pista” (track) style.
- Material: Usually available in high-grade carbon steel or polished stainless.
2. Dogster Escapamentos
Dogster has gained massive popularity for its “Gomos” (segmented) curves. These are handmade by welding multiple small rings of steel together, which allows for extremely precise airflow control.
- Feature: Often features a “ponteira externa” (external muffler) that can be easily repacked with glass wool to maintain the sound quality.
3. Sarachú
A classic choice that offers a more balanced approach. Sarachú pipes are often preferred by riders who want a significant power gain without the extreme noise levels of a Dore.
4. Pro Tork (Original Style)
If you are restoring a vintage RD 135 to factory specifications, Pro Tork remains the go-to for affordable, OEM-style replacements that keep the bike’s classic silhouette.
Material Comparison: Steel vs. Inox
In 2026, we see a shift toward Inox (Stainless Steel). While more expensive, it offers several advantages:
| Feature | Carbon Steel (Chrome/Black) | Stainless Steel (Inox) |
| Durability | Prone to rust if not maintained | Highly resistant to corrosion |
| Weight | Heavier | Significantly lighter |
| Heat | Retains heat longer | Dissipates heat faster |
| Aesthetics | Classic look, but can blue/yellow | Remains shiny or turns “titanium blue” |
Maintaining a high-performance exhaust is just as important as how long do car batteries last or regular oil changes; neglect leads to power loss and engine damage.
Technical Setup: Carburetion is Key
You cannot simply bolt on a high-performance escapamento dimensionado and ride. Because these pipes pull more air through the engine, your bike will likely run “lean” (not enough fuel).
- Re-jetting: You will need to increase the size of the main jet in your Mikuni or Keihin carburetor.
- Spark Plug Check: After a few miles, check your spark plug color. It should be “chocolate brown.” If it’s white, you are running too lean and risk seizing the piston.
- Air Intake: Consider a high-flow air filter to match the increased exhaust flow for maximum horsepower gains.
FAQ: Frequently Asked Questions
Is a “Dimensionado” exhaust legal for street use?
In many regions, aftermarket exhausts must meet specific decibel limits. While many RD 135 pipes are sold for “competition use,” some models from brands like Sarachú offer baffles to stay within legal sound limits.
How do I clean my RD 135 exhaust?
For Inox pipes, use neutral soap and water. Never use harsh chemicals or abrasives on “blue” finished pipes, as it will strip the heat-treated coloring.
Does a sports exhaust reduce engine life?
If the carburetor is tuned correctly, no. However, if the bike runs lean due to the new exhaust, it can cause the engine to overheat and fail prematurely.
