1. Motorcycle Frames Offers
  2. sku: 18174982419576762
  3. HONDA 50100-128-670EC

HONDA 50100-128-670EC Frame Trailsport

fits model: St90, St. make: Honda. year: 1973–1990.

50100-128-670ec Honda Frame St90 Trailsport St 90 73

( Manufacturer Part Number: 50100-128-670EC ), ( Type: Frame ), ( Manufacturer Warranty: No Warranty ), ( Country Of Origin: Japan ), ( Location: 4e6m 7384 )

Review HONDA Frame Trailsport fits ST90 ST 1973–1990

The **Honda 50100-128-670EC Frame (ST90 Trailsport 90, 1973)** is a meticulously crafted, original aftermarket replacement frame designed to restore or enhance the structural integrity and aesthetic appeal of your classic 1973 Honda Trailsport 90. This frame is a direct, high-quality substitute for the factory unit, ensuring a perfect fit with minimal modifications required, making it an ideal choice for both restoration projects and enthusiasts seeking to preserve the authenticity of their vintage motorcycle. Constructed from durable, high-strength steel, the frame is engineered to maintain the original riding dynamics and handling characteristics of the Trailsport 90, while also providing the added benefit of improved corrosion resistance compared to some older factory frames. The design retains the iconic, minimalist aesthetic of the era, with clean lines and a compact footprint that complements the Trailsport 90 s utilitarian yet stylish dual-sport heritage. Whether you re rebuilding a project bike, replacing a worn or damaged frame, or simply upgrading for long-term durability, this frame delivers a seamless blend of functionality and authenticity. Its compatibility with the 1973 model ensures that all critical mounting points for the engine, swingarm, suspension, and controls align precisely, allowing for a straightforward installation process. For riders who appreciate the raw, unadulterated spirit of the early dual-sport era, this frame offers a reliable way to maintain the integrity of their Honda while benefiting from modern aftermarket craftsmanship.

### **Pros and Cons of Buying a 1973 Honda ST90 Trailsport (Frame #50100-128-670EC)**

#### **Pros**

1. **Classic Design and Nostalgia** The ST90 is a well-regarded classic dirt bike from Honda s early trailbike era. It has a timeless, retro aesthetic that appeals to collectors and enthusiasts who appreciate vintage machinery.

2. **Reliable Honda Engine** Honda engines of this era are known for their durability and simplicity. The 90cc single-cylinder engine is straightforward, making it easier to maintain than modern high-performance bikes.

3. **Lightweight and Maneuverable** At around 100 120 lbs (depending on condition), the ST90 is easy to handle, making it suitable for smaller riders or those who prefer a nimble trail bike.

4. **Minimalist Maintenance** With fewer electronic components than modern bikes, repairs and upkeep are often simpler and less expensive. Basic maintenance (chain, spark plug, carburetor) can be done with basic tools.

5. **Potential for Restoration** If the bike is in rough shape, a well-executed restoration could significantly increase its value, especially if it s kept in original or period-correct condition.

6. **Low Operating Costs** Fuel efficiency is excellent for its size, and parts are still relatively affordable compared to modern dirt bikes.

7. **Historical Significance** As one of the first successful trail bikes from Honda, it holds a place in off-road history, making it attractive to hobbyists and historians.

8. **Easy to Modify** The simplicity of the design allows for easy modifications, such as upgrading the carburetor, exhaust, or suspension for better performance.

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#### **Cons**

1. **Age and Wear** A 1973 bike will likely have significant wear, especially if it hasn t been well-maintained. Rust, worn-out suspension, and a degraded engine are common issues.

2. **Limited Power** The 90cc engine is underpowered by today s standards, making it unsuitable for aggressive riding or steep terrain. It s best suited for light trails and casual use.

3. **Outdated Safety Features** Modern dirt bikes have better braking systems, suspension, and ergonomics. The ST90 lacks disc brakes, modern suspension tuning, and rider-friendly controls.

4. **Parts Availability** While Honda parts are still available, some specialized components (e.g., original suspension, carburetors) may be harder to find or require reproduction parts.

5. **No Modern Comforts** The seat, handlebars, and footpegs are basic by today s standards, which could lead to discomfort on longer rides.

6. **Potential for Hidden Damage** Without a thorough inspection, issues like frame cracks, seized bearings, or internal engine damage may not be immediately obvious.

7. **Resale Value Depends on Condition** Unlike modern bikes, a restored ST90 may not hold significant resale value unless it s in pristine condition or part of a collection.

8. **Not Suitable for Aggressive Riding** The lightweight frame and weak engine make it ill-equipped for jumps, high-speed riding, or rough terrain compared to modern trail bikes.

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### **Conclusion and Recommendation**

Buying a **1973 Honda ST90 Trailsport** is a decision best made by someone who values **nostalgia, simplicity, and the challenge of maintaining a classic bike** rather than modern performance. If you re looking for a **fun, low-cost, and easy-to-repair trail bike** for light use, light trails, or as a project, this bike could be a great fit especially if you re willing to invest time in restoring or maintaining it.

However, if you re seeking **modern reliability, power, or comfort**, this bike is not the best choice. It s better suited for:

- **Enthusiasts who enjoy vintage machinery** and don t mind its limitations.

- **Budget-conscious riders** who prioritize simplicity over performance.

- **Those who plan to restore it** as a hobby rather than use it frequently.

**Final Recommendation:**

- **Buy it if:** You re okay with its age, limitations, and potential maintenance challenges, and you either plan to ride it lightly or restore it as a passion project.

- **Avoid it if:** You need a bike for serious trail riding, expect modern reliability, or want something more powerful and comfortable.

Before purchasing, **inspect it thoroughly** (or have a mechanic do so) for frame integrity, engine condition, and suspension health. If it s in rough shape, factor in restoration costs before committing.

Details:

Freshly repainted frame and swing arm.

part #: 50100128670ec prices

  • $135.66-$700.00

specifications mocycfra:

  • for models: St90, St
  • for makes: Honda
  • for years: 1973-1990
  • mpn: 50100-128-670ec
  • type: Frame
  • manufacturer warranty: No Warranty
  • country of origin: Japan
  • location: 4e6m 7384

offer mocycfra:

  • sold: 0
  • options: Seller-arranged-local-pickup
  • quantity: 1
  • started: May 20, 2026
  • best offers: True
  • availability: In Stock

seller mocycfra:

  • # reviews: 160
  • city: York, Pennsylvania
  • rating: 100.0%

returns mocycfra:

  • policy: No Returns

payments mocycfra:

  • wallet: Paypal
  • credit card: Mastercard
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shipping mocycfra:

general mocycfra:

  • Motorcycle Scooter Parts Accessories > Body Frame > Frames Parts
  • condition: Used
for models: st90, st, for makes: honda, for years: 1973-1990, type: frame, manufacturer warranty: no warranty, country of origin: japan, location: 4e6m 7384,
category: motorcycle parts > motorcycle scooter parts accessories > body frame > frames parts, sku: 18174982419576762,
Honda 50100-128-670EC Is Similar To:
mocycfra logo
2 offers $135.66–$700.00 USD
  • Used. Offer #1 priced at $135.66 + $204.45 shipping estimate = $340.11* total. Condition is "Used" Frame Honda ST90 Trailsport ST 90 73.+$204.45 shipping
  • Used. Offer #2 priced at $700.00 + $Calculated shipping estimate = $700.00* total. 1973 year. Freshly repainted frame and swingarm.+$Calculated shipping

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