KTM 546.03.002.000 Rear Frame 300MX

( Manufacturer Part Number: 546.03.002.000 ), ( Type: Subframe )

Review KTM Oem Rear Sub Frame Subframe Support fits 1990

The **KTM 300 MX 1990 model, specifically the rear frame identified as part number 03.002.000**, represents a rare and highly sought-after component from one of the most iconic off-road motorcycles of its era. Produced by KTM, a brand synonymous with innovation and performance in the motocross world, this frame exemplifies the engineering prowess of the late 1980s and early 1990s. Crafted from high-grade chromoly steel, the frame is designed with a lightweight yet robust construction, ensuring durability under the extreme stresses of high-speed jumps, sharp turns, and aggressive riding. The geometry of the frame is optimized for agility and responsiveness, featuring a compact wheelbase and a low center of gravity, which were revolutionary advancements for the time. This design allowed riders to navigate technical trails with precision while maintaining stability at high speeds. The rear frame, in particular, plays a critical role in the bike s suspension dynamics, housing the swingarm and rear shock absorber mount, which contribute significantly to the bike s overall handling and comfort. The 1990 iteration of the KTM 300 MX was part of a series that gained widespread acclaim for its balance of power and maneuverability, making it a favorite among both amateur and professional riders. The rear frame from this model is not merely a functional part but a piece of automotive history, reflecting the evolution of motocross technology. For collectors, restorers, or enthusiasts seeking to preserve or enhance the performance of a classic KTM, this frame is a prized addition, embodying the spirit of adventure and mechanical ingenuity that defined the sport during its golden age. Its authenticity and condition can greatly influence its value, making it a coveted find for those who appreciate the heritage and craftsmanship of vintage off-road machinery.

### **Pros and Cons of Buying a 1990 KTM 300MX (Frame #KTM 546.03.002.000)**

#### **Pros**

1. **Classic KTM Reliability** KTM motorcycles of the early 1990s were known for their robust, air-cooled single-cylinder engines, which were durable and relatively low-maintenance compared to modern high-revving twins.

2. **Off-Road Capability** The 300MX was designed for motocross and enduro, featuring a lightweight frame, suspension tuned for rough terrain, and a strong clutch/braking system for its time. It remains a capable off-road bike for casual trail riding or light motocross.

3. **Simplicity** The engine is straightforward, with fewer electronic components than modern bikes, making repairs and maintenance easier for those with mechanical skills.

4. **Parts Availability** As a classic KTM, parts (especially frames, forks, and engine components) are still relatively accessible, though not as widely available as on newer models.

5. **Nostalgia & Collectibility** For enthusiasts, owning a well-preserved 1990s KTM can be a point of pride, especially if it s in good condition. Some collectors value early KTM models.

6. **Lower Cost of Ownership** Fuel efficiency was better than modern bikes, and insurance/registration costs are typically lower than for high-performance modern enduro bikes.

7. **Lightweight & Maneuverable** The frame is designed for agility, making it easier to handle on technical trails compared to heavier modern bikes.

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#### **Cons**

1. **Age & Wear** A 1990 bike will likely have significant mileage, wear on the frame, suspension, and engine components. Rust, bent frames, or seized bearings are common issues.

2. **Outdated Technology** The bike lacks modern features such as disc brakes (it likely has drum brakes), electronic fuel injection (it uses carbureture), and advanced suspension tuning. This makes it less capable on pavement or in high-speed situations.

3. **Poor Fuel Economy Compared to Modern Bikes** While better than most bikes of its era, it will still drink fuel compared to modern efficient enduro bikes.

4. **Limited Comfort for Long Rides** The ergonomics, seat, and wind protection are basic by today s standards, making it less suitable for long-distance touring.

5. **Reliability Concerns** The air-cooled single-cylinder engine is prone to overheating if pushed hard, and the lack of modern diagnostics makes troubleshooting harder.

6. **Safety Risks** Drum brakes and a weak frame (compared to modern materials) reduce stopping power and crash protection. Modern helmets, armor, and safety standards were not as advanced in the '90s.

7. **Resale Value** Unlike modern KTM enduro bikes, this model has little to no resale value unless it s a rare or well-preserved collector s item.

8. **Environmental & Noise Regulations** Some areas have restrictions on older, noisier bikes, and emissions standards may not meet modern requirements.

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### **Conclusion & Recommendation**

Buying a **1990 KTM 300MX with frame #KTM 546.03.002.000** depends entirely on your intended use, budget, and willingness to invest in restoration.

- **If you want a project bike for off-road fun, mechanical learning, or nostalgia**, this could be a rewarding purchase especially if you find one with a solid frame, good engine, and minimal rust. Expect to spend significant time and money on repairs, upgrades (like modern brakes or suspension), and maintenance.

- **If you seek a reliable, safe, and capable enduro bike for regular riding**, a modern KTM 350/500 EXC-F or similar would be a far better choice due to superior technology, safety, and comfort.

- **If you re a collector or appreciate classic bikes**, this could be a fun addition to a garage just be prepared for higher maintenance costs and limited practical use.

- You have mechanical skills and enjoy restoration projects.

- You re riding it mostly for trail fun in a controlled environment (not high-speed or pavement).

- You re okay with spending extra on upgrades (brakes, suspension, engine work).

- You want a bike for daily riding without constant repairs.

- You prioritize modern safety, comfort, and reliability.

- You re looking for a bike with good resale value.

For most riders today, a **modern KTM 350/500 EXC-F or similar** would be a far superior investment offering better performance, safety, and longevity while still being affordable. However, if you re drawn to the classic KTM experience and willing to put in the work, this frame could be a fun and rewarding challenge.

Details:

1990 KTM 300MX OEM REAR BACK SUB FRAME SUBFRAME SUPPORT 546.03.002.0 This subframe is in good condition with normal signs of wear. Removed From: 1990 KTM 300 MX, Please review all pictures to assess the condition of item. Note that this subframe has been painted yellow. All tabs and brackets are present undamaged.

Please review all photos carefully for item condition and what is included. All mounting points are straight and secure, with intact threaded holes no cracks.

part #: 54603002000 prices

• $78.74-$123.53

specifications mocycfra:

• for makes: Ktm
• for years: 1990
• mpn: 546.03.002.000
• type: Subframe

general mocycfra:

• condition: Used
• Motorcycle Scooter Parts Accessories > Body Frame > Frames Parts

offer mocycfra:

• started: May 4, 2026
• sold: 0
• availability: In Stock
• options: Ship-to-home
• quantity: 1

seller mocycfra:

• city: Virginia Beach, Virginia
• rating: 99.9%
• # reviews: 4314

shipping mocycfra:

• cost: $0.00
• type: Fixed
• class: Standard
• carrier: UPS
• service: UPS Ground
• transit: 3-7 Days

payments mocycfra:

• other
• wallet: Google-pay
• credit card: Discover

returns mocycfra:

• paid by: Buyer
• policy: Returns Accepted
• time: 30 Days

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