If you grew up in Brazil from the late 90s to early 2010s, you know exactly what I am talking about as soon as that screech starts. That high-pitched, angry-bee-meets-chainsaw howl that gets dogs barking, mothers reaching for earplugs and 16-year-old boys everywhere falling in love at once.
That, guys, is the famous escapamento RD Boom-Boom — the exhaust that made the good ol’ Yamaha RD 135 be known as the king of favelas, terror of avenues and official sound-track from an all-time generation.
First the bike that got it all rolling
The Yamaha RD 135 (also known as the RD 135Z in some markets) was a small two stroke motorcycle introduced in Brazil for street use in 1993. From a distance, it resembled a mosquito on steroids: skinny tires, no fairings to speak of, seat foam thinner than the average credit card and a power-to-weight ratio that made it comically quick for something that you could buy off the shelf with pocket change left over from what Fiat charged for its cheapest old Uno.
Stock, it already sounded mean. But Brazilians don’t do “stock.”
Insert the escapamento esportivo RD — the aftermarket expansion-chamber pipe that turned the bike from a “nippy little commuter” into a “rolling war crime.”
The secret of the RD exhaust system that turned it into a religion
The sound
I really can’t do it justice in words. It’s a metallic, raspy, ear-piercing wail that begins at 6,000 rpm and only grows louder into a scream that tickles your ribcage at 10,500 rpm. They’d record it with their potato-quality Nokia phones and the same way teenagers today record Travis Scott concerts.
It was cheap as hell
A nice escapamento RD (such as ones from brands like Pro Tork, Fortuna, Polimet or the mythical „Dominator”) were around R$ 150–250 in the beginning of the 2000‘s. Let’s put it this way; instead of two pairs of Oakleys you could make your bike sound like a GP racer and pick up anywhere between 4-6 ponies. It was one that any broke teenager with a part-time job could afford.
In fact, it made the bike faster
Two-strokes love expansion chambers. The right RD pipe added a wicked midrange/top-end surge that made the puny 135 into a giant killer. There are also countless tales of RD 135s smoking CBR 900RRs and even Hayabusas in the quarter (well, maybe not, but let me have this).
The golden age: 2002–2008
It was the zenith of “escapamento RD” culture.
Customers in every city had some guy with a welder and a grinder who could knock-off them a Fortuna Dimension in 2 days Facebook was not yet invented, but Orkut groups “RD 135 SÓ O CANO” and “RDzeiras do Brasil” had hundreds of thousands of members posting videos titled “RD CANTANDO LINDO NA FRENTE DA ESCOLA,” The police hated them. Politicians tried to ban them. Mothers wrote letters to newspapers. And every time we tried to shut them down, the kids just loved them even more.
There was a hand gesture even: you hold your arm behind your ear as if to say, I’m not listening when an RD flew past shrieking. Everyone did it. Even grandmas.
The legendary models
There is not one RD rider who did not have his personal favorite among the exhausts. The Mt. Rushmore:
Pro Tork Dimension – the purest, most flawless weld. Sounded like a pissed off hornet in a metal box. Fortuna Competition – the loudest. Could wake up a patient in a coma at 200 meters. Polimet Cobra -black paint, looked cool, a little quieter resonance but deeper tone. Dominator (réplica) – the unicorn. Hand-made, unobtanium, allegedly picked up 8 hp and sounded like God clearing his throat.
The rituals
Having an RD with a sport exhaust wasn’t just a means of getting around. It was theater.
Warming up the engine in front of your crush’s house for 15 minutes at 11 p.m. 180 on the avenue driving it to listen to the echo that was bouncing off of the walls. Rev-limiter bounce, the holy “corte de giro” at every red light, tbone and overpass Capturing it on your friend’s Sony Ericsson K750i and getting it uploaded to YouTube with the title “RD 135 CANTANDO MUITO 2010” (still online, still boasting over 2 million views)
The slow death (2010–today)
The party was killed a number of ways:
The noise laws were instituted so the Feds actually enforced them (and used db meters!) Yamaha ceased production of two-stroke and street legal motorcycles in Brazil The RD 135 got old. Really old. See if you can get a job that’s held together by more than duct tape and prayers Youngsters upgraded to CG 160s with “escapamento dobom” or electric scooters (the horror)
But the legend never died.
2025 status: the return no one saw coming
Guess what? It will be 2025 all over again with the RD escapamento revival.
Babies who were in this world to guys and gals born in 2005 are now rebuilding RDs, searching original Fortuna pipes on Mercado Livre for R$2.000,00 and uploading videos in 4K with drone takes! There are Whatsapp groups of 500 people who just buy and sell used expansion chambers. Clean original paint RD 135s with an Dimension pipe are now worth more than a new Honda Elite scooter.
And yes — they still pull up the hand-behind-the-ear thing when one screams past.
Final thoughts
The RD escapamento wasn’t just a hunk of metal. It was resistance, not in bomb form but in tubular steel. It was what sounded like being young, broke and impervious in a country where everything else seemed impossible.
You may never have owned one, but you felt it in your chest when one flew past at midnight. It reeked of scorched castor oil and freedom.
So if you happen to be walking down some random street in São Paulo, Rio, Recife or a dusty little interior city tonight and you suddenly hear that unmistakable metallic scream bouncing around between the buildings…
