HONDA 51220-HA7-670 Front Left Knuckle Hub Brake Axle

( Manufacturer Part Number: 51220-HA7-670 ), ( Type: Knuckle Spindle )

Review HONDA Front Left Knuckle Hub Brake Axle Assembly fits TRX350 TRX 350 4X4 1986

The **Honda 51220-HA7-670 1986 TRX350/4X4 Front Left Knuckle, Hub, and Brake Axle Assembly** is a meticulously engineered, high-performance suspension component designed exclusively for the iconic **Honda TRX350 4x4**, a legendary off-road utility vehicle from the late 1980s. This front left axle assembly represents a critical junction of durability, precision, and off-road capability, combining the **knuckle, hub, and brake axle** into a single robust unit that ensures reliable handling, braking, and articulation under the most demanding conditions. Crafted from high-strength steel, the knuckle features a reinforced ball-joint mounting system, allowing for smooth pivoting motion while maintaining structural integrity even when subjected to extreme off-road stresses, such as deep mud, rocky terrain, or aggressive wheel articulation. The integrated **hub assembly** is designed with a sealed bearing system, minimizing friction and wear while providing smooth rotational movement for the front wheels, a crucial factor for both on-road stability and off-road maneuverability. The **brake axle** is engineered to accommodate the TRX350 s drum brake system, featuring precise alignment points for the brake shoe assembly, ensuring consistent stopping power and reducing the risk of brake drag or uneven wear. This assembly is a direct replacement part, meticulously manufactured to match the original Honda specifications, including critical dimensions such as bolt patterns, spindle lengths, and mounting hole spacing, ensuring a perfect fit for restoration projects or performance upgrades. Whether restoring a vintage TRX350 to its original glory or enhancing its off-road prowess with aftermarket modifications, this front left axle assembly delivers the reliability and performance expected from Honda s legendary engineering proving that even decades-old off-road machinery can continue to conquer challenging terrain with confidence.

### **Pros and Cons of Buying a 1986 Honda TRX350 (TRX350 4x4) Front Left Knuckle, Hub, Brake, and Axle Assembly (Part #: 51220-HA7-670)**

1. **Reliability and Durability** Honda s TRX350 (and its successor, the TRX400) is known for its robust off-road design, and many of its components, including the front axle and knuckle assembly, are built to withstand heavy use. The 1986 model, while older, benefits from Honda s reputation for mechanical longevity in ATVs.

2. **Compatibility** The part number **51220-HA7-670** is a direct replacement for the front left knuckle, hub, brake, and axle assembly on the **1986 Honda TRX350**. This means it should fit without modification, assuming the rest of the frame and suspension are intact.

3. **Off-Road Performance** The TRX350 was designed for rugged terrain, and its front axle is part of its 4WD system. Replacing a worn or damaged knuckle/axle assembly can restore proper articulation, steering, and braking, which is crucial for off-roading.

4. **Ease of Installation** As a complete assembly (knuckle, hub, brake, and axle), this part should simplify the repair process compared to sourcing individual components. Many aftermarket and OEM parts for this era require additional machining or alignment work, but this bundled part minimizes those concerns.

5. **Potential for Restoration** If you re restoring a classic TRX350, sourcing original or high-quality aftermarket parts like this can help maintain authenticity while improving reliability. The knuckle and axle are critical for proper handling and safety.

6. **Cost-Effective Repair** Replacing a failed knuckle or axle can be cheaper than repairing a bent frame or replacing multiple worn components. If the rest of the ATV is in decent shape, this could be a cost-effective way to get it back on the trail.

7. **Availability of Supporting Parts** While parts for older ATVs can be scarce, Honda s TRX350/400 series still has a dedicated following. You may find additional suspension, brake, or steering components if needed, though sourcing may require online marketplaces or specialty shops.

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1. **Age and Wear** The **1986 TRX350** is over 30 years old, and many original components (including the knuckle and axle) may already be worn out. If the rest of the ATV s frame, suspension, or steering is compromised, replacing just this assembly won t fully resolve underlying issues.

2. **Limited Aftermarket Support** Unlike newer ATVs, the TRX350 has limited aftermarket upgrades or modifications. If you re looking for modern performance enhancements (e.g., larger brakes, upgraded suspension), this part may not integrate well without additional work.

3. **Potential for Counterfeit or Low-Quality Parts** Older Honda parts, especially those sourced from third-party sellers, can sometimes be fakes or poorly manufactured. Verify the seller s reputation and consider purchasing from a trusted dealer or Honda parts specialist to ensure authenticity.

4. **Compatibility Risks** While the part number suggests a direct fit, slight variations in frame or suspension geometry could arise from modifications or wear. A professional inspection or alignment may be needed post-installation to ensure proper function.

5. **High Mileage Concerns** If the ATV has been heavily used, the knuckle and axle may have accumulated significant wear. Replacing them won t fix issues like bent frames, seized bearings, or degraded suspension, which could lead to recurring problems.

6. **Difficulty Finding Labor** Older ATVs require specialized mechanics. If you re not experienced with Honda off-road vehicles, finding a shop familiar with the TRX350 s quirks (e.g., unique bolt patterns, suspension geometry) may be challenging.

7. **Cost of Additional Repairs** If the knuckle or axle failure is due to a larger issue (e.g., frame damage, improper maintenance), replacing just this part could lead to further expenses down the line. A thorough inspection of the entire front end is recommended before purchase.

8. **Environmental and Safety Risks** Older ATVs may not meet modern safety standards (e.g., brakes, rollover protection). If you plan to use this ATV frequently, consider upgrading other safety-critical components (e.g., brakes, tires, exhaust).

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- The rest of the ATV is structurally sound.

- You re replacing a failed component rather than addressing a systemic issue.

- You source the part from a reputable seller to avoid fakes or low-quality replacements.

- You re prepared for potential additional repairs (e.g., suspension, steering, or frame checks).

- The ATV has been neglected for years with unknown damage.

- You re looking for modern performance upgrades rather than restoration.

- You lack mechanical experience or access to specialized labor.

- Bent or cracked knuckles.

- Seized or worn bearings.

- Frame damage around the axle mounts.

- Proper alignment of the steering and suspension.

2. **Verify Part Authenticity** Purchase from a **Honda-authorized dealer, a trusted online marketplace (eBay, Facebook Marketplace with verified sellers), or a specialty ATV parts shop**. Avoid suspiciously cheap offers that may indicate counterfeit parts.

3. **Consider a Full Front-End Overhaul** If the ATV has high mileage or unknown history, replacing just the knuckle/axle may not be enough. Budget for:

- Steering components (rack, pins, bushings).

- Suspension (forks, shocks, springs).

- Brake system (drums, cables, calipers if applicable).

- Frame inspection for cracks or welds.

- Proper steering response.

- No unusual noises (grinding, clunking).

- Even brake engagement.

- Correct wheel alignment.

5. **Alternative Options**

- If the ATV is beyond repair, consider **restoring a newer TRX400 (1988 1992)**, which shares many parts with the TRX350 but benefits from slight improvements.

- If you re focused on off-roading, evaluate whether a **modern ATV (e.g., Honda TRX250X, Can-Am Outlander)** would better suit your needs with modern safety and performance features.

The **51220-HA7-670 assembly is a sound replacement part** for a **1986 TRX350** if the rest of the ATV is in decent condition. However, **treat it as a targeted repair rather than a full restoration**. If you re unsure about the ATV s condition, prioritize a **pre-purchase inspection** or consider a **newer model** if off-roading is your primary use. For enthusiasts restoring classic ATVs, this part can be a **cost-effective way to revive a beloved machine** just be prepared for potential follow-up repairs.

Details:

It all depends on the size and weight of items. The pivots are good. It has some surface rust. It includes everything pictured.

It is straight. It does not have any cracks. It may have some surface scratches, but no mechanical problems. Ratings for Item Condition.

It has some scratches and wear marks. We most often are able to combine shipping if multiple items purchased. Domestic Shipping. EXCELLENT: This is a new part that still in the package and perfect condition.

The threads are good.DOES NOT ROTATE FROZEN. FAIRLY GOOD: This is a used part that in good working order but has larger amount of cosmetic damage. It is still a usable part. The splines are good.

Or it is a part with small mechanical problem but still usable. This item is in FAIR condition.

part #: 51220ha7670 prices

• $16.99-$69.00

specifications wheehucyc:

• for models: Trx350, Trx, 350, 4x4
• for makes: Honda
• for years: 1986
• mpn: 51220-ha7-670
• type: Knuckle Spindle

general wheehucyc:

• condition: Used
• Motorcycle Scooter Parts Accessories > Wheels, Tires Parts > Wheel Hubs

seller wheehucyc:

• city: Hayden, Idaho
• rating: 99.7%
• # reviews: 41123

offer wheehucyc:

• quantity: 1
• options: Ship-to-home
• sold: 0
• availability: In Stock
• started: March 31, 2026

returns wheehucyc:

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

payments wheehucyc:

• other
• wallet: Paypal
• credit card: Visa

shipping wheehucyc:

• transit: 3-7 Days
• type: Calculated
• carrier: USPS, UPS
• class: Standard, Expedited
• service: USPS Ground Advantage, USPS Priority Mail, UPS Ground
• cost: $27.27

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