YAMAHA 90508-35071-00 Torsion Spring YA6

( Type: Torsion Spring ), ( UPC: 905083507100 )

Review YAMAHA Ya6 Oem Torsion Spring And Guide fits 125 1966

The **Yamaha 90508-35071-00 1966 YA6 125 Torsion Spring** is a meticulously crafted, high-performance component designed exclusively for Yamaha s iconic YA6 125cc motorcycle, a classic model from the mid-1960s renowned for its timeless engineering and sporty handling. This torsion spring is a precision-engineered part of the bike s front suspension system, playing a critical role in maintaining optimal ride quality, steering responsiveness, and overall mechanical integrity. Crafted from durable, high-grade steel, the spring is built to withstand the demands of both daily commuting and spirited riding, ensuring consistent performance even after extensive use. Its robust construction and carefully calibrated tension provide the perfect balance between comfort and control, allowing riders to navigate rough terrain with ease while retaining the sharp, agile feel that the YA6 is celebrated for. Whether restoring a vintage YA6 to its original glory or upgrading an existing bike for enhanced performance, this torsion spring is an essential replacement part that upholds Yamaha s legacy of precision and reliability. Its compatibility with the 1966 model ensures a seamless fit, allowing enthusiasts and mechanics alike to restore the bike s suspension to factory specifications with confidence. For those who appreciate the blend of classic design and modern engineering, this spring is a testament to Yamaha s enduring commitment to quality, making it a must-have for any YA6 owner seeking to preserve or elevate their riding experience.

The **Yamaha YA6 125 torsion spring (part number 90508-35071-00, circa 1966)** is a classic component for restoring or maintaining vintage Yamaha motorcycles. Below is a detailed breakdown of its pros and cons, followed by a conclusion and recommendation.

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### **Pros of buying a Yamaha YA6 125 Torsion Spring**

1. **Authentic Restoration**

The torsion spring is a critical part of the YA6 s suspension system, which uses a torsion bar to absorb front-wheel movement. A genuine or high-quality replica ensures the bike s original handling characteristics are preserved, which is essential for collectors and enthusiasts who prioritize authenticity.

2. **Compatibility with Classic YA6 Models**

The YA6 (1964 1967) was Yamaha s first mass-produced motorcycle, and this torsion spring is specific to its front suspension. If you re restoring or maintaining a YA6, this part is non-negotiable for proper function.

3. **Durability and Longevity**

Torsion springs are designed to withstand repeated stress over time. A well-maintained original spring or a high-quality aftermarket replacement can last for decades, especially if the bike is used occasionally. This reduces long-term maintenance costs compared to other suspension components that may wear out faster.

4. **Ease of Installation**

The torsion spring is relatively straightforward to install, requiring basic mechanical skills and standard tools. Many YA6 owners and mechanics have experience working with this system, making repairs less intimidating.

5. **Availability of Supporting Parts**

Since the YA6 is a classic bike, many aftermarket suppliers and restoration shops carry torsion springs, clamps, and related hardware. This makes it easier to source additional parts if needed during the process.

6. **Preservation of Ride Quality**

The torsion bar suspension provides a unique, slightly stiff but responsive ride that is characteristic of early Japanese motorcycles. Replacing a worn or broken spring restores this feel, which is desirable for riders who appreciate the bike s original engineering.

7. **Potential for Customization**

While the stock spring is ideal for stock handling, some riders experiment with aftermarket torsion bars or springs to adjust stiffness for modern riding preferences. The availability of the original part allows for such modifications if desired.

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### **Cons of buying a Yamaha YA6 125 Torsion Spring**

1. **Age and Wear of Original Parts**

If purchasing an original torsion spring from a dismantled YA6, there is a risk that it may already be weakened or cracked due to age, rust, or previous misuse. Testing the spring s flexibility or replacing it with a new replica is recommended to avoid premature failure.

2. **Limited Aftermarket Options**

Unlike more modern or popular bikes, the YA6 torsion spring is not widely produced by major aftermarket brands. This means you may need to rely on specialty suppliers, eBay, or restoration shops, which could increase costs or lead times.

3. **Potential for Counterfeit or Low-Quality Replicas**

Some sellers may offer "replica" or "new" torsion springs that are not actually genuine Yamaha parts. These may be made from inferior materials or improperly machined, leading to premature failure or poor performance. Always verify the supplier s reputation and material quality before purchasing.

4. **Specialized Knowledge Required**

Installing or replacing a torsion spring requires understanding how the suspension system works. Misalignment or incorrect installation can lead to handling issues, premature wear on other components (such as the fork tubes or steering head bearings), or even accidents. Beginners may need guidance from an experienced mechanic.

5. **Cost Relative to Value**

Depending on the source, a genuine or high-quality torsion spring can be expensive, especially if sourced from a reputable restoration shop. For riders who are not deeply invested in the bike s authenticity, the cost may not justify the purchase if the bike is not a primary project.

6. **Rust and Corrosion Risks**

If the spring is removed from a bike that has been stored in damp conditions, rust can form on the spring or its mounting points. This requires thorough cleaning and lubrication to prevent future issues, adding to the maintenance effort.

7. **Limited Longevity in Harsh Conditions**

While torsion springs are durable, they can degrade faster if the bike is ridden aggressively, exposed to extreme temperatures, or subjected to off-road use. Riders who push their bikes hard may need to replace the spring more frequently than casual users.

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### **Conclusion**

The **Yamaha YA6 125 torsion spring (90508-35071-00)** is a vital part for restoring or maintaining a classic YA6, offering authenticity, durability, and a ride quality that is hard to replicate. However, it comes with challenges such as limited aftermarket options, the risk of counterfeit parts, and the need for specialized knowledge to install or replace it correctly.

For **collectors, restorers, or enthusiasts** who prioritize the bike s originality and historical accuracy, this part is worth the investment. For **casual riders or those not deeply committed to the YA6 s heritage**, the cost and maintenance effort may outweigh the benefits, especially if the bike is not a primary project.

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### **Recommendation**

- **Purchase from a reputable source**, such as a trusted restoration shop, eBay seller with positive reviews, or a parts dealer specializing in classic Yamahas. Avoid suspiciously cheap offers that may indicate counterfeit or low-quality parts.

- **Inspect the spring** for rust, cracks, or signs of wear before installation. If purchasing a used spring, test its flexibility by gently twisting it it should feel firm but not brittle.

- **Consider a new replica** if an original is unavailable. Look for suppliers that specify "new" or "replacement" springs made from high-grade steel. Brands like **Yamaha Parts** (if still available) or **specialty restoration suppliers** are safer bets than generic eBay sellers.

- **Follow installation guidelines** carefully. Many online resources (e.g., YA6 forums, restoration manuals) provide step-by-step instructions. If unsure, consult a mechanic experienced with vintage Yamaha suspensions.

- **Evaluate whether the bike is worth the effort**. If the YA6 is a hobby project with limited riding, the cost of parts like the torsion spring may not be justified. Consider whether a more modern or easier-to-maintain bike would better suit your needs.

- **Explore alternatives** such as aftermarket suspension kits (if available) or modifying the bike to use simpler components (e.g., replacing the torsion bar with a modern fork if the bike is being used for casual rides).

- Once installed, **regularly check the torsion spring** for rust or wear, especially if the bike is stored in damp conditions. Lubricate the spring and its mounting points as needed to extend its lifespan.

Ultimately, the **Yamaha YA6 torsion spring is a worthwhile investment for purists**, but it requires careful sourcing, installation, and maintenance to ensure reliability. For those not deeply invested in the bike s heritage, the effort may not be worth the reward.

Details:

BIN #41L, Please review all pictures to assess the condition of item. Removed From 2009 KAWASAKI KX250. 1966 YAMAHA YA6 125 OEM TORSION SPRING AND GUIDE, This torsion spring is in very good condition and shows normal signs of wear.

part #: 905083507100 prices

• $9.99-$38.97

specifications cyclevintagee:

• for models: 125
• for makes: Yamaha
• for years: 1966
• type: Torsion Spring
• upc: 905083507100

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• started: May 28, 2026
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• condition: Used
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• # reviews: 7392

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