Yamaha RD350 Specification Sheet: A Deep Dive into the Classic Two-Stroke Legend

The Yamaha RD350 is a timeless icon in the world of classic two-stroke motorcycles, revered by enthusiasts for its raw power and unmistakable exhaust note. Whether you're a proud owner or an admirer of vintage bikes, understanding the RD350’s specifications and maintenance needs is key to keeping this legend alive. In this article, we’ll explore the spec sheet for the RD350B, compare it to the Indian RD models, and provide port maps to help you tune your bike to perfection. Let’s dive into the details that make the RD350 a standout in motorcycle history.

How to Maintain Your Yamaha RD350: Tips for Longevity

Maintaining a Yamaha RD350 isn’t just about keeping it running—it’s about preserving a piece of two-stroke heritage. Regular oil checks, especially the 2-stroke oil mix, are crucial to prevent engine seizures, a common woe for these bikes. Cleaning the carburetors, inspecting the reeds, and ensuring the exhaust isn’t clogged will keep the bike purring. The spec chart below, featuring the RD350B, offers a detailed look at what powers this machine. While most technical specs align closely with the Indian RD models, the brake horsepower (BHP) is a notable difference—something enthusiasts often tweak for that extra thrill. Whether you ride it daily or showcase it at vintage rallies, a little care goes a long way with the RD350.

Understanding the RD350B Specification Sheet

The RD350B spec sheet is a treasure trove of information for anyone obsessed with this two-stroke beast. From its 347cc air-cooled parallel-twin engine to its 6-speed gearbox, the RD350B was designed for performance. While the Indian RD350 variants (High Torque and Low Torque) share many similarities, the RD350B’s power output—often rated at around 39 BHP in the US—sets it apart from the slightly detuned Indian models, which hovered around 27-30 BHP depending on the version. This difference stems from tuning variations and emission regulations, but it’s nothing a skilled rider can’t tweak with the right know-how.

Port Mapping for Yamaha RD350: Tuning Your Two-Stroke Engine

Porting is where the magic happens for RD350 enthusiasts looking to unlock more power. The port map for the RD350B, courtesy of Erlenbach Racing, is a handy guide if you’re aiming to match US-spec performance. It outlines the exhaust, transfer, and intake port timings—critical for optimizing combustion and boosting horsepower. If you’ve got an Indian RD350 and dream of that extra kick, this map is your starting point. Just be sure to pair it with a good expansion chamber and rejetting for the full effect.

Port Map for Indian RD350 LT: Low Torque Explained

The Indian RD350 Low Torque (LT) model was built for efficiency and reliability, sacrificing some of the raw power seen in its international siblings. Its port map reveals a more conservative design, with timings that prioritize smoother power delivery over peak performance. This made the LT a favorite for daily riders in India during the 1980s, offering decent mileage alongside that classic two-stroke buzz. If you’re restoring an LT, this map will guide you back to factory specs—or inspire a custom tune if you’re feeling adventurous.

Port Map for Indian RD350 HT: High Torque Unleashed

The Indian RD350 High Torque (HT) is the wilder sibling, tuned for a bit more grunt than the LT. Its port map shows slightly more aggressive timings, giving it an edge in acceleration and top-end power—closer to the RD350B but still toned down for Indian roads. Owners of the HT often rave about its ability to rip through traffic or cruise effortlessly on open highways. Whether you’re rebuilding an HT or tweaking it for modern use, this port map is your blueprint to keeping its spirit alive.

Why the Yamaha RD350 Remains a Vintage Motorcycle Icon

Decades after its debut, the RD350 still holds a special place in the hearts of riders worldwide. Its blend of lightweight agility, two-stroke simplicity, and tunable performance makes it a dream for collectors and mechanics alike. On your website, rd350.info, this spec sheet and port map collection can serve as a valuable resource for fellow RD350 lovers. Whether you’re chasing the thrill of a perfectly ported engine or just keeping your bike roadworthy, the RD350’s legacy is one worth celebrating.