HARLEY-DAVIDSON 150-353 Flywheel Motor 61

( Brand: Harley-davidson ), ( Manufacturer Part Number: 150-353 ), ( Part Type: Flywheel Motor ), ( Vintage Part: Yes )

Review HARLEY DAVIDSON Ohv Flywheel 61 Inch Motor fits KNUCKLEHEAD 1936-40

The **Harley-Davidson 150-353 Knucklehead Flywheel (1936 1940, 61 Motor)** is a legendary component from one of the most iconic eras in motorcycle history, embodying the raw, unrefined spirit of Harley-Davidson s early powerhouse engines. This flywheel, part of the famed **Knucklehead** series, was produced during a transitional yet groundbreaking period when Harley-Davidson was pushing the boundaries of performance and engineering. The **61 motor** designation refers to the engine s displacement, specifically a **74-cubic-inch (1,212cc)** version of the legendary **V-twin**, which was a significant upgrade from the earlier, smaller-displacement models. The flywheel itself is a robust, cast-iron piece, designed to handle the immense torque and power generated by the Knucklehead s overhead-valve (OHV) design a radical departure from Harley s previous pushrod layouts. Its knuckle-shaped valve covers, which gave the engine its name, were not only stylish but also functional, housing the camshafts and rocker arms that drove the overhead valves, dramatically improving breathing and performance.

This flywheel is a critical part of the **1936 1940 Knucklehead** lineup, a model that was both a fan favorite and a technical marvel. The **150-353** designation likely refers to the flywheel s weight (150 pounds) and its **353-inch pounds of torque** (a figure that, while exaggerated for marketing, underscores the engine s brute strength). The flywheel itself is forged from heavy-duty cast iron, designed to withstand the high RPMs and sustained power delivery that made Knuckleheads legendary on the racetrack and the open road. Its **61 motor** variant was particularly prized for its balance of power and reliability, making it a favorite among customizers, restorers, and enthusiasts who seek the authentic Harley-Davidson experience. The flywheel s **magneto mounting flange** and **crankshaft alignment** are meticulously engineered to ensure smooth operation, while its **spoke-style design** (common in early Harley-Davidsons) adds to its vintage charm.

Beyond its mechanical significance, this flywheel is a piece of automotive history, representing Harley-Davidson s bold shift toward overhead-valve technology in the late 1930s. The Knucklehead era was a turning point, setting the stage for future Harley-Davidson innovations while also cementing the brand s reputation for bold engineering. Whether installed in a fully restored **1938 Model 61 Knucklehead** or used in a modern custom project, this flywheel carries the weight of Harley s legacy its unmistakable growl, its unapologetic power, and its timeless appeal. For collectors, restorers, and riders who appreciate the raw, unpolished soul of vintage motorcycles, the **Harley-Davidson 150-353 Knucklehead Flywheel (1936 1940, 61 Motor)** is not just a part it s a piece of the past that continues to turn heads and ignite passion.

### Pros and Cons of Buying a Harley-Davidson 150-353 Knucklehead (1936-1940) with a 61 Motor

1. **Historical Significance and Rarity** The Knucklehead is one of the most iconic and sought-after Harley-Davidson models, representing the early days of American motorcycle manufacturing. Owning one places you in a small but passionate community of enthusiasts who appreciate its heritage.

2. **Unique Design and Aesthetic** The Knucklehead s distinctive knucklehead ignition system, exposed valve springs, and classic V-twin engine design make it instantly recognizable. Its retro styling appeals to collectors and vintage motorcycle fans.

3. **Strong Community and Support** Due to its rarity, there is a dedicated group of owners, restorers, and mechanics who share knowledge, parts, and restoration tips. Clubs like the Knucklehead Owners Club provide networking opportunities and events.

4. **Potential for Restoration and Customization** Many Knuckleheads are in need of restoration, offering an opportunity to work on a project bike. Restoration can be deeply rewarding, and some owners modify them with modern components while preserving their vintage look.

5. **Investment Potential** Well-preserved Knuckleheads can appreciate in value, especially if they are rare or have historical significance. Some models, particularly those with originality or provenance, are considered collector s items.

6. **Driving Experience** The 61 motor (introduced in 1936) is a significant upgrade over earlier engines, offering better performance and reliability. While still raw by modern standards, it provides a raw, unfiltered riding experience that enthusiasts find exhilarating.

7. **Nostalgia and Passion** For many, owning a Knucklehead is about the love for vintage motorcycles, the thrill of riding a piece of history, and the camaraderie of the motorcycle community.

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1. **High Maintenance and Restoration Costs** Knuckleheads are not "drive-and-ride" motorcycles. Many require extensive restoration work, including engine rebuilding, frame repairs, and electrical system updates. Parts can be expensive, especially for rare or discontinued components.

2. **Reliability Issues** Even with a 61 motor, the engine and drivetrain components are prone to wear over time. Common problems include valve spring failures, piston ring leaks, and transmission wear. Regular maintenance is essential, but even then, breakdowns can occur.

3. **Limited Modern Comfort and Safety** Modern motorcycles offer features like disc brakes, ABS, suspension tuning, and ergonomic designs that Knuckleheads lack. Riding one can be less comfortable and more physically demanding, especially on long trips.

4. **Fuel and Emissions Challenges** Older motorcycles often struggle with modern fuel standards. Lead-free gasoline can cause engine issues, and some states have emissions regulations that may require modifications or retrofits, adding to the cost.

5. **Insurance and Legal Restrictions** Insuring a Knucklehead can be costly due to its value and potential repair expenses. Some areas may have restrictions on vintage motorcycles, such as noise limits or registration requirements.

6. **Limited Availability of Parts** While the Knucklehead community is strong, some parts are hard to find. Replicas and aftermarket components exist, but they may not match the original quality or fit perfectly.

7. **Time-Consuming Ownership** Owning a Knucklehead is not just about riding; it s a lifestyle. Restoration projects, maintenance, and participation in the community can consume significant time and effort.

8. **Resale Value Uncertainty** While some Knuckleheads appreciate in value, others may depreciate if they are not well-maintained or lack historical significance. The market for vintage Harleys can be unpredictable.

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Buying a Harley-Davidson Knucklehead (1936-1940) with a 61 motor is a deeply rewarding experience for those who appreciate vintage motorcycles, mechanical challenges, and the thrill of riding a piece of automotive history. It is not, however, a practical choice for casual riders or those seeking a modern, low-maintenance motorcycle. The decision ultimately depends on your priorities: if you value heritage, passion, and the joy of restoration over convenience and reliability, a Knucklehead can be an incredible addition to your collection. If you prioritize ease of use, modern comfort, and minimal upkeep, this motorcycle may not be the right fit.

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1. **Assess Your Goals** Decide whether you want a project bike for restoration or a rideable motorcycle. Be honest about the time and resources you can commit to maintenance.

2. **Inspect Thoroughly** Have the motorcycle inspected by a knowledgeable mechanic or Knucklehead specialist. Look for signs of rust, engine wear, and electrical issues. Prioritize models with original or well-documented restoration work.

3. **Budget for Restoration** Set aside a significant budget for repairs, parts, and potential unexpected expenses. Restoration costs can easily exceed $10,000 or more, depending on the bike s condition.

4. **Join the Community** Engage with Knucklehead owners and clubs for advice, parts sourcing, and support. Websites like the Knucklehead Owners Club forum or Facebook groups are valuable resources.

5. **Consider a Ridable Example** If you want to ride the motorcycle immediately, seek out a Knucklehead that is already restored or in good working condition. Avoid "brutal" examples unless you are prepared for extensive work.

6. **Store It Properly** If you won t be riding it frequently, store the motorcycle in a dry, secure location to prevent rust and damage.

7. **Enjoy the Journey** Whether you restore it yourself or work with professionals, the process of bringing a Knucklehead back to life can be incredibly fulfilling. Embrace the challenges and the community that comes with owning such a unique machine.

In summary, a Knucklehead is a fantastic choice for the right owner one who is passionate about vintage motorcycles and willing to invest time and effort into preserving its legacy. For others, it may be better to explore modern classics or other vintage bikes that offer a balance of history and practicality.

Details:

Fr This is for a 61 motor, not 74. This is for a 61 motor, not 74 threads are good as well shaft tapers.never sandblasted. USA buyers, lower 46. Do your homework on all possible applications.

Preserved well.

part #: 150353 prices

• $100.00-$479.99

specifications cyclevintagee:

• for models: Knucklehead
• for makes: Harley
• for years: 1936-40
• brand: Harley-davidson
• mpn: 150-353
• part type: Flywheel Motor
• vintage part: Yes

seller cyclevintagee:

• city: Random Lake, Wisconsin
• rating: 100.0%
• # reviews: 1378

offer cyclevintagee:

• sold: 0
• availability: In Stock
• started: February 25, 2026
• best offers: True
• options: Ship-to-home
• quantity: 1

shipping cyclevintagee:

• service: Economy
• transit: 3-7 Days
• type: Fixed
• cost: $24.94
• class: Economy

general cyclevintagee:

• condition: Used
• Parts Accessories > Motorcycle Scooter Parts Accessories > Other Motorcycle Scooter Parts Accessories

payments cyclevintagee:

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• wallet: Google-pay
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returns cyclevintagee:

• policy: No Returns

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