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The Yamaha 350 two stroke street bike stands as an icon in the world of classic motorcycles. Famed for its raw power, distinctive engine note, and unmistakable style, this legendary machine has captured the hearts of enthusiasts worldwide. Despite being decades old, the Yamaha 350 two stroke street bike continues to enjoy a cult following, with owners proudly showcasing meticulously restored or preserved models at motorcycle shows, on social media, and at vintage rallies. In this comprehensive guide, we will delve into the history, technical details, unique characteristics, maintenance tips, and cultural significance of the Yamaha 350 two stroke street bike. Whether you’re a dedicated aficionado or a curious newcomer, you’ll learn why this motorcycle has become such a revered classic in the motorcycling community.

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1. A Brief History of the Yamaha 350 Two Stroke Street Bike

Yamaha has long been known for producing innovative motorcycles, and its two-stroke legacy is deeply ingrained in motorcycle history. One of its most iconic offerings is the Yamaha 350 lineup, with the Yamaha RD350 often singled out as the shining example of the brand’s prowess in the 1970s. The RD series itself came from a lineage that included the R5, which paved the way for what became the RD (Race Derived) series. This evolution was largely in response to growing competition in the mid-displacement motorcycle segment, especially from British and other Japanese manufacturers.

1. Emergence and Popularity
   The Yamaha 350 two stroke street bike burst onto the scene in the early 1970s, right when motorcycle enthusiasts were seeking lighter, faster, and more affordable machines. Its agility, combined with a powerful two-stroke engine, provided a riding experience that was thrilling yet accessible. The RD350, in particular, quickly gained a reputation as a “giant killer,” often outperforming larger displacement four-stroke bikes of its time.
2. Cultural Context
   Motorcycling in the 1970s was characterized by a sense of rebellion and freedom. Riders sought machines that offered raw performance and spirited riding dynamics. The Yamaha 350 two stroke street bike, with its punchy powerband and nimble handling, fit perfectly into that mold. It became an aspirational ride for young enthusiasts seeking both performance and value.
3. Transition into Modern Times
   By the late 1970s, two-stroke street motorcycles faced increasing emissions restrictions and pressure from environmental regulations. While Yamaha continued to refine its two-stroke technology for various segments, including dirt bikes and racing applications, the writing was on the wall for large-capacity two-stroke street bikes. The RD350 eventually made way for four-stroke successors. However, thanks to its passionate fanbase, the Yamaha 350 two stroke street bike has never truly faded from the public’s consciousness. Restored examples remain a prominent fixture in the vintage motorcycle community, showcasing the enduring charm of this classic machine.

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2. Technical Overview and Performance

At the heart of the Yamaha 350 two stroke street bike lies its distinctive engine. Built for performance, these two-stroke twins were known for delivering surprising levels of power in a compact package. Understanding the bike’s technical aspects offers insight into what makes this motorcycle so special.

1. Engine Configuration
   • Type: 347cc two-stroke parallel twin
   • Cooling: Air-cooled
   • Power Output: Depending on the model and region, the horsepower output varied. For example, the RD350 often boasted around 39-40 horsepower in stock trim, which was remarkable for its displacement in the 1970s.
   • Torque: A strong midrange torque ensured that riders had accessible power in the rev range for spirited acceleration.
2. Carburetion and Fueling
   Two-stroke engines rely heavily on precise carburetion, given that the fuel-oil mixture is integral to both engine lubrication and combustion. The Yamaha 350 two stroke street bike typically used two separate carburetors—one for each cylinder—to ensure optimal power delivery. Tuning and synchronizing these carburetors is essential for performance and reliability.
3. Chassis and Handling
   • Frame: A tubular steel frame provided a balance of rigidity and lightweight performance.
   • Suspension: Conventional telescopic forks in the front and dual shock absorbers in the rear were the norm in that era. These gave adequate comfort and impressive handling characteristics, especially on twisty roads.
   • Braking: Early models often sported a front disc brake and a rear drum brake, though the specifics varied by model year and market. The front disc brake was a significant performance upgrade over drum brakes, improving stopping power for the relatively fast and light motorcycle.
4. Powerband and Riding Experience
   One hallmark of a two-stroke street bike is the “powerband”—the range of RPM within which the engine delivers its peak power. For the Yamaha 350 two stroke street bike, this powerband is relatively narrow but incredibly exhilarating. Riders often describe the feeling of hitting the sweet spot as both thrilling and addictive, accompanied by the unmistakable two-stroke exhaust note that roars with authority.
5. Oil Injection System
   Yamaha’s Autolube system was a significant innovation for its time, eliminating the need to pre-mix oil and fuel manually. This system greatly improved convenience, as riders only had to keep a separate oil reservoir filled, and the engine would draw oil as needed to maintain proper lubrication.

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3. Key Models in the Yamaha 350 Two Stroke Family

While the RD350 is arguably the most famous of Yamaha’s 350cc two-stroke street bikes, there are a few noteworthy variants and related models that enthusiasts often group under the same banner. These include the R5 (a precursor to the RD series), the RD350B, the RD350F, and even the lesser-seen models marketed in specific countries. Each has its unique features and nuances, but all share the core essence of a thrilling two-stroke riding experience.

1. Yamaha R5
   The R5 was released before the RD series officially launched. It laid the groundwork with a 350cc two-stroke twin, and while it lacked some of the refinements that would come later, its spirited performance set the stage for Yamaha’s success in this category.
2. Yamaha RD350 (Early and Later Generations)
   • RD350A / RD350B: Early RD350 models introduced subtle improvements over the R5, such as reed valve induction in certain markets, a front disc brake, and improved oil injection.
   • RD350F and Subsequent Variants: These later versions incorporated technological advances and updated styling elements. Depending on the region, you might find differences in porting, exhaust design, and even the presence or absence of a catalytic exhaust system (in later variants).
3. Yamaha RD350LC and Beyond
   The RD350LC (Liquid Cooled) was a successor that retained the two-stroke parallel twin concept but added liquid-cooling. While the LC models represented a significant evolution, some purists still favor the air-cooled models for their raw feel and simpler mechanics.

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4. Maintenance and Care for a Yamaha 350 Two Stroke Street Bike

Owning a vintage Yamaha 350 two stroke street bike can be an immensely rewarding experience. However, the care and maintenance of these bikes demand both attention to detail and a willingness to learn. While two-stroke engines are famously simpler in design than four-strokes, their tuning can be finicky. Here are some essential tips to keep your classic Yamaha 350 running smoothly:

1. Frequent Oil Changes and Quality Oil
   Although the Autolube system handles lubrication, you’ll still want to ensure you’re using high-quality two-stroke oil specifically formulated for motorcycles. Regularly checking the oil pump adjustment is also crucial to prevent engine damage and fouling.
2. Carburetor Cleaning and Synchronization
   Because the two-stroke engine relies heavily on perfect air-fuel mixing, the carburetors must be kept clean and properly synchronized. Blocked jets or poorly adjusted floats can lead to poor performance, excessive smoking, and potential engine damage.
3. Spark Plug Inspection
   Spark plugs can reveal a lot about how well (or poorly) your engine is running. If they’re consistently fouled or showing signs of lean or rich conditions, it’s a clue that your carburetors need tuning. Always use the recommended heat range and replace the plugs regularly to maintain reliability.
4. Exhaust System Maintenance
   Two-stroke exhaust systems can accumulate carbon deposits over time. Periodic cleaning or decarbonizing of the exhaust pipes and mufflers can help maintain optimal performance and keep that iconic two-stroke sound crisp.
5. Regular Inspection of Seals and Gaskets
   The Yamaha 350 two stroke street bike depends on proper crankcase compression to operate efficiently. Leaks in crank seals or gaskets can cause performance issues and potential engine damage. Regular inspections and timely replacements keep the bike running at its best.
6. Brake and Suspension Checks
   While the engine often gets the lion’s share of attention, the brakes and suspension also need regular maintenance, especially for safety. Ensure the brake pads and shoes are in good condition, and replace worn fork seals or shock absorbers to maintain stability and handling.

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5. Performance Tuning and Modifications

One factor that makes the Yamaha 350 two stroke street bike so beloved is its tunability. Many owners enjoy personalizing and improving their motorcycles, whether for additional performance or unique aesthetics. Below are some common modifications:

1. Expansion Chambers
   Replacing the stock exhaust with performance expansion chambers can significantly improve power output, especially in the mid to high RPM range. However, it may also make the bike louder, so be mindful of local noise regulations.
2. Carburetor Upgrades
   Upgrading the stock carburetors or installing performance jet kits can fine-tune fuel delivery. This ensures your engine runs with optimal air-fuel ratios, potentially offering a boost in horsepower and torque.
3. Porting and Polishing
   Porting the cylinders and polishing the intake and exhaust tracts can enhance the engine’s breathing efficiency. This modification, while advanced, can unlock noticeable gains when done by an experienced tuner.
4. Performance Ignition
   Modern electronic ignitions can replace older contact breaker points. This leads to more reliable spark timing, improved throttle response, and potentially better fuel economy.
5. Suspension Upgrades
   Although the vintage charm of the Yamaha 350 two stroke street bike is undeniable, the original suspension components might feel dated by modern standards. Upgraded fork springs, adjustable rear shocks, and even fork braces can enhance stability and cornering prowess.
6. Aesthetic Customization
   Many riders choose to customize the look of their Yamaha 350. From powder-coating the frame to adding retro racing stripes, the possibilities are endless. Keep in mind that preserving stock parts can increase the bike’s value in the eyes of collectors.

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6. Collectibility and Market Value

Vintage motorcycle enthusiasts often regard the Yamaha 350 two stroke street bike as a worthwhile investment, both for its historical significance and its mechanical appeal. Prices for these bikes can vary widely, based on factors like condition, originality, and regional availability.

1. Rarity
   Early models in mint condition or those with unique features (such as limited-edition paint schemes) can fetch higher prices. Over the years, many of these bikes were wrecked, neglected, or heavily modified, making original and fully functional units increasingly scarce.
2. Condition and Authenticity
   • Concours Restorations: A bike restored to “better than new” condition, using original parts, will often command a premium.
   • Survivor Bikes: Some collectors favor bikes that remain largely unrestored but well-preserved, showing the patina of age.
   • Modified Units: While custom modifications can enhance performance, heavily altered bikes might not be as appealing to purists. However, they can still draw interest from those who value personal expression and enhanced capabilities.
3. Documentation and Provenance
   Having a clear record of ownership, maintenance, and restoration increases a bike’s desirability. Original sales paperwork, period brochures, and historical records can also provide valuable context and potentially boost resale value.

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7. The Riding Experience

One reason the Yamaha 350 two stroke street bike continues to enchant riders is the visceral nature of the riding experience. Modern motorcycles, with their electronic aids and quieter exhausts, often lack the raw, mechanical feel that vintage two-stroke bikes provide.

1. Sound and Sensation
   The iconic ring-ding-ding exhaust note and the scent of two-stroke oil evoke nostalgia and adrenaline in equal measure. The immediate throttle response, combined with a light chassis, makes carving corners a joy.
2. Engaging with the Machine
   Because the powerband is narrower than modern four-strokes, riders have to actively work the gearbox, keeping the engine in its sweet spot. This fosters a sense of connection and skillful engagement that can be lost on more automated bikes.
3. Community and Camaraderie
   Vintage motorcycle gatherings are often filled with kindred spirits who share a passion for these timeless machines. The Yamaha 350 fosters lively conversations about restoration, tuning, and riding exploits, creating a sense of community that’s difficult to replicate with newer motorcycles.

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8. Common Challenges and Considerations

While the Yamaha 350 two stroke street bike is undeniably appealing, it’s not without its challenges. Prospective owners or new enthusiasts should be aware of some hurdles they might face:

1. Parts Availability
   Although the strong enthusiast community and aftermarket support make finding parts easier than for some other vintage bikes, certain components can be scarce or expensive, especially original bodywork and engine internals.
2. Maintenance Frequency
   Two-stroke engines typically require more frequent care, including decarbonizing exhaust ports, replacing spark plugs, and ensuring proper carburetor tuning. Neglect can quickly lead to performance issues.
3. Environmental Regulations
   Depending on your region, emissions and noise regulations might limit the bike’s street legality or require specific modifications. Always check local laws before riding or modifying your Yamaha 350.
4. Engine Rebuilds
   Because these engines work at higher RPMs and rely on precise lubrication, they may require top-end rebuilds (piston, rings) more regularly compared to modern four-stroke powerplants. However, the relative simplicity of a two-stroke often makes these rebuilds more approachable for mechanically inclined owners.

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9. Why the Yamaha 350 Two Stroke Street Bike Remains Relevant

With so many modern motorcycles offering cutting-edge performance and technology, why does the Yamaha 350 two stroke street bike still command such respect?

1. Simplicity and Charm
   For many enthusiasts, the allure of a simpler mechanical era is strong. The Yamaha 350’s relatively straightforward design and ease of customization make it an inviting prospect for hands-on owners.
2. Historical Significance
   This bike represents a pivotal time in motorcycle history, when two-strokes were at the forefront of both performance and innovation. Its success on the streets and race tracks cemented Yamaha’s reputation for building fast, reliable motorcycles.
3. Community and Heritage
   Vintage motorcycles often attract passionate communities dedicated to preserving and celebrating these mechanical gems. Owning a Yamaha 350 two stroke street bike means joining a worldwide network of collectors, racers, restorers, and weekend warriors.
4. Investment Potential
   While not every old motorcycle will appreciate in value, certain models—particularly iconic ones like the Yamaha 350—tend to hold or even increase in worth over time. This makes the bike appealing not only from a rider’s perspective but also from a collector’s viewpoint.

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10. Tips for Prospective Buyers

If you’re in the market for a Yamaha 350 two stroke street bike, doing your homework is essential. Here are some key considerations to keep in mind:

1. Research and Understand the Models
   Familiarize yourself with the different iterations of the RD350 (and related models like the R5), their differences, and specific quirks. Knowing exactly which version you want helps narrow your search and informs negotiations.
2. Inspection
   Always inspect a potential purchase in person, if possible. Look for signs of rust, frame damage, or poorly executed modifications. Check compression and look into service history records, if available.
3. Test Ride
   If the seller permits it, a short test ride can reveal issues with power delivery, clutch engagement, or transmission operation. Pay attention to unusual vibrations, rattles, or difficulty shifting.
4. Authenticity and Originality
   If you aim to collect or restore to showroom condition, verify the originality of parts like the tank, body panels, engine numbers, and frame numbers. Ask for receipts and documentation from any restoration work.
5. Budget for Maintenance
   Even a well-preserved Yamaha 350 two stroke street bike might require some level of maintenance, tuning, or part replacement. Factor these costs into your purchase decision.

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11. Restoring a Yamaha 350: Challenges and Rewards

A proper restoration project can be both challenging and immensely satisfying. Bringing a neglected Yamaha 350 back to life involves dedication, patience, and resourcefulness. Here are some restoration insights:

1. Planning and Budgeting
   Set clear goals for your restoration. Are you aiming for a concourse-level rebuild or a reliable rider? Establishing a budget and timeline can help keep the project on track.
2. Sourcing Parts
   While certain parts remain readily available through aftermarket suppliers, some items—like vintage bodywork or rare trim pieces—can be harder to find. Joining online forums, social media groups, and attending vintage bike swaps can be invaluable for tracking down elusive components.
3. Documenting Your Progress
   Taking photos and notes throughout the restoration process not only keeps you organized but also serves as a record of the bike’s transformation. This can add value if you ever decide to sell or showcase your Yamaha 350.
4. Learning and Skill Development
   Restoring a vintage motorcycle is a crash course in mechanical engineering, problem-solving, and patience. You’ll likely acquire new skills, from carburetor tuning to paintwork, which can be applied to future projects.
5. The Joy of the Final Product
   Once completed, there’s a profound sense of accomplishment in hearing the two-stroke engine fire up for the first time after you’ve painstakingly rebuilt it. The finished bike becomes a rolling testament to your effort and love for classic motorcycles.

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12. Yamaha 350 Two Stroke Street Bike in Popular Culture

Over the years, the Yamaha 350 two stroke street bike has appeared in films, magazines, and stories that celebrate the golden era of motorcycle performance. Its relatively small displacement yet surprisingly robust power has made it a favorite among custom builders and café racer enthusiasts as well. References to the RD350 specifically pop up in countless “top classic bikes” lists, underscoring its enduring legacy.

1. Racing Pedigree
   The RD in RD350 stands for “Race Derived,” which is a nod to Yamaha’s storied racing heritage. Track and street racers alike took advantage of the bike’s lightweight frame and formidable power-to-weight ratio to challenge larger, more expensive machines.
2. Motorcycle Shows and Rallies
   It’s not uncommon to see pristine examples of the Yamaha 350 at motorcycle shows and rallies dedicated to classic or vintage bikes. Enthusiasts often trade stories of epic rides, near-mythical performance feats, and restoration triumphs centered around this iconic machine.
3. Influence on Modern Motorcycles
   Although modern bikes have largely moved away from two-stroke technology due to emissions standards, the Yamaha 350’s influence can be seen in the continuing pursuit of lightweight, performance-oriented designs. Many modern street bikes aim to replicate the same thrilling power delivery and nimble feel that the RD350 delivered decades ago.

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13. Preserving the Legacy: Modern Appreciation of a Classic

In a world increasingly dominated by electronic aids, four-stroke powertrains, and ever-tightening emissions regulations, owning and riding a Yamaha 350 two stroke street bike is almost a statement of rebellion. It’s a homage to the era when simplicity, mechanical creativity, and visceral feedback defined the riding experience.

1. Supporting Enthusiast Communities
   Online forums, Facebook groups, and local clubs help keep the spirit of the Yamaha 350 alive. These communities organize rides, share maintenance tips, and often collaborate on group buys for hard-to-find parts.
2. Events and Meetups
   Vintage motorcycle events, both formal and informal, offer an excellent opportunity for Yamaha 350 owners to show off their bikes and learn from fellow enthusiasts. Participation in such gatherings fosters camaraderie and keeps interest in the model vibrant.
3. Museum Exhibits and Collections
   Some transportation museums and private collections feature the Yamaha 350 among their exhibits. This recognition cements the bike’s status as more than just a motorcycle—it’s an artifact of motorcycling’s storied past.

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14. Conclusion: The Enduring Allure of the Yamaha 350 Two Stroke Street Bike

For decades, the Yamaha 350 two stroke street bike has enthralled riders with its distinctive blend of agility, power, and character. From its breakthrough performance in the 1970s to its revered status among vintage motorcycle enthusiasts today, this bike embodies the spirit of an era defined by innovation and freedom on two wheels.

• Historical Significance: As a pioneer in mid-displacement two-stroke performance, it set new standards for what was achievable in a small and affordable package.
• Technical Marvel: From the narrow powerband to the Autolube system, every facet of the bike showcases Yamaha’s technical ingenuity.
• Community and Culture: The enduring fanbase speaks volumes about the bike’s impact on motorcycling culture. Its presence at shows, in private collections, and on sunny weekend rides continues to spark excitement and conversation.
• Collectibility: Original, well-maintained examples are becoming rarer, driving up values and adding a layer of mystique.
• Riding Experience: Few motorcycles can rival the raw, engaging ride of a two-stroke twin, and the Yamaha 350 remains a standout in this regard.

Whether you’re a seasoned collector, an amateur restorer, or simply someone who appreciates mechanical art, the Yamaha 350 two stroke street bike is worth your admiration. It represents a golden chapter in motorcycle history—an era when innovation and passion combined to create machines that continue to inspire and thrill riders long after they first appeared on the streets. Even as technology surges forward, the timeless appeal of this classic two-stroke endures, proving that some pieces of motorcycling heritage are simply too iconic to fade away.