TAIL LIGHT STL89 73 P21/5W

( Brand: Tail Light ), ( Manufacturer Part Number: STL89 ), ( Type: Tail Light Assembly ), ( Bulb Shape Code: P21/5w ), ( Light Color: Clear ), ( Housing Color: Chrome ), ( Wattage: 5 W ), ( Lens Color: Red ), ( Placement On Vehicle: Rear ), ( Lighting Technology: Incandescent )

Review TAIL LIGHT Motorcycle Assembly Harley Davidson 73 P21/5w fits ROAD KING 1998

The **STL89 Tail Light Assembly** for Harley-Davidson s **1973 1998 Road King models (P21/5W series)** is a meticulously crafted, high-performance aftermarket replacement designed to restore both the iconic aesthetic and functional brilliance of these legendary motorcycles. Engineered to match the original factory specifications with precision, this tail light assembly features a **durable, amber-tinted polycarbonate lens** that ensures optimal visibility while maintaining the classic Road King s timeless look. The housing is constructed from **heavy-duty die-cast aluminum**, providing superior strength and resistance to corrosion, ensuring longevity even under harsh riding conditions. Inside, a **high-output LED or incandescent bulb (depending on model variant)** is housed in a sealed, waterproof compartment, guaranteeing reliable illumination in all weather from rain-soaked highways to dusty backroads. The mounting bracket is designed for a **perfect, factory-fit alignment**, eliminating any wobble or misalignment that could compromise both aesthetics and functionality. Whether you re restoring a vintage Road King to its original glory or upgrading an older model for modern reliability, this tail light assembly delivers a seamless blend of heritage and performance. Built to withstand the demands of long-distance cruising, it ensures that your Harley not only turns heads with its classic silhouette but also meets today s safety standards with uncompromising clarity. Ideal for collectors, restorers, and enthusiasts who demand nothing less than perfection, this component is a testament to Harley-Davidson s enduring legacy where craftsmanship meets the open road.

### **Pros and Cons of Buying a 1973 1998 Harley-Davidson Road King (STL89) Tail Light (P21/5W)**

1. **Authentic Vintage Look** The P21/5W tail light is a classic Harley-Davidson design, fitting well with the original aesthetic of the Road King models from the 1970s to mid-1990s. It enhances the bike s retro appeal, especially if you re restoring or maintaining period-correct styling.

2. **Durability and Reliability** Harley-Davidson components, even older ones, are known for their robustness. The tail light assembly (including the bulb housing and wiring) is built to last, provided it is in good condition.

3. **Ease of Replacement** Since these lights are widely available (especially from aftermarket suppliers and Harley parts dealers), sourcing a replacement is straightforward. Many are sold as complete assemblies, making installation relatively simple.

4. **Compatibility with Modifications** If you re working on a custom or restored Road King, this tail light will integrate seamlessly with other period-accurate parts, such as the fuel tank, fenders, and exhaust.

5. **Lower Cost Compared to Modern Parts** Vintage Harley parts, while not always cheap, are often more affordable than brand-new OEM or aftermarket components for newer models. This can be a budget-friendly choice if you re restoring an older bike.

6. **Functionality** The P21/5W tail light serves its purpose effectively, providing proper illumination and turn signals (if equipped with a turn signal kit). The bulb socket is standard, so replacing bulbs is easy.

7. **Community Availability** Harley-Davidson enthusiasts and restoration groups often share tips on sourcing and installing vintage parts. Online forums (e.g., Harley-Davidson forums, eBay, or specialty shops) make it easier to find compatible replacements.

---

1. **Age-Related Wear and Potential Failure** Older tail lights may have degraded wiring, cracked lenses, or failing bulbs. If the unit is from a bike that wasn t well-maintained, it might require additional repairs beyond just replacing the light.

2. **Limited Modern Compatibility** If you re running modern electronics (e.g., LED bulbs, digital dashboards, or aftermarket lighting systems), the P21/5W may not integrate perfectly. Some modern wiring or connectors might not match, requiring additional modifications.

3. **Bulb Availability** While the bulb socket is standard, finding the exact vintage bulb (e.g., a 12V incandescent tail/brake light bulb) can be tricky. Some modern bulbs may not fit perfectly or may not provide the same light output.

4. **Potential for Counterfeit Parts** When buying online, there s a risk of receiving a knockoff or poorly made replica. Always verify the seller s reputation and check for authenticity (e.g., Harley-Davidson branding, correct part numbers).

5. **Installation Challenges** If the bike has been heavily modified (e.g., custom frames, non-standard wiring), fitting the tail light may require extra effort, such as extending wires or adjusting mounting points.

6. **Environmental Factors** Older tail lights may be more susceptible to damage from weather (e.g., rain, UV exposure) if the lens or housing isn t sealed properly. This could lead to electrical issues over time.

7. **Limited Customization Options** Unlike modern aftermarket lights, the P21/5W has limited styling or performance upgrades. If you want LED or high-performance lighting, you ll likely need to replace the entire assembly.

---

The **P21/5W tail light for a 1973 1998 Harley-Davidson Road King** is a solid choice if you prioritize **authenticity, ease of replacement, and cost-effectiveness** for a vintage bike. It s ideal for restorers, classic enthusiasts, or those who want to maintain the original look of their Road King. However, if you re running modern electronics or seeking high-performance lighting, you may need to supplement it with additional components.

For most **restoration projects or period-correct builds**, the pros outweigh the cons, making it a practical and stylish option. If you re unsure about the condition of the unit, inspect it thoroughly or test it before purchasing to avoid hidden issues.

---

- **Buy it if:** You re restoring a Road King to its original condition, want a classic look, and don t mind dealing with vintage parts. Ensure the light is functional and the wiring is intact.

- **Consider alternatives if:** You re running modern lighting systems, need LED upgrades, or want a more durable, weather-sealed unit. In that case, look for **aftermarket vintage-style tail lights** (e.g., from brands like **Harley-Davidson Performance Parts, Race Day, or Screamin Eagle**) that offer modern improvements while maintaining a retro aesthetic.

- **Where to buy:** Check **Harley-Davidson authorized dealers, eBay (with verified sellers), specialty motorcycle parts shops, or restoration forums** for authentic P21/5W units. Always verify the part number and condition before purchasing.

For the best results, pair this tail light with other **period-accurate components** (e.g., 1970s 90s Harley fenders, fuel tanks, and exhaust) to complete the look. If in doubt, consult a **Harley restoration expert** for guidance on compatibility.

Details:

No bulb is included. Please see all photos.

part #: stl89 prices

• $26.89-$65.00

specifications cyclerearbrake:

• for models: Road, King
• for makes: Harley, Davidson
• for years: 1998
• brand: Tail Light
• mpn: Stl89
• type: Tail Light Assembly
• bulb shape code: P21/5w
• light color: Clear
• housing color: Chrome
• wattage: 5 W
• lens color: Red
• placement on vehicle: Rear
• lighting technology: Incandescent

offer cyclerearbrake:

• quantity: 1
• best offers: True
• started: June 10, 2026
• options: Ship-to-home
• availability: In Stock
• sold: 0

shipping cyclerearbrake:

• type: Calculated
• service: USPS Ground Advantage
• carrier: USPS
• transit: 5-12 Days
• cost: $15.10
• class: Standard

payments cyclerearbrake:

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

returns cyclerearbrake:

• policy: No Returns

general cyclerearbrake:

• Motorcycle Scooter Parts Accessories > Lighting Lamps > Tail Brake Light Assemblies
• condition: New other see deTails

seller cyclerearbrake:

• city: Prattville, Alabama
• # reviews: 5801
• rating: 99.9%

Tail Light STL89 Is Similar To:

• 0000-006 Ky Led Tail Light Integrated Turn Signal Yamaha (25.8% similar) Ky ultra-bright led Tail Light integrated turn signal Yamaha r6 R6S...(September 28th, 2018)
• 000685 No School Choppers Ford Model Stainless Tail Light Glass Lens (23.6% similar) Glass lens, no plastic here. License plate Light on bottom of bezel to illuminate LP. Shipping costs are based on the method that you choose. Has two screws on back for custom mounting. 30 day money back guarantee free expert tech support we eat, sleep, live love motorcycles. The mounting studs are...(October 31st, 2018)
• 001204 No School Choppers Ford Model Blacked Out Tail Light Glass (19.9% similar) These Lights measure in diameter, deep. Glass lens, no plastic here. License plate Light on bottom of bezel to illuminate LP. Has two screws on back for custom mounting. The mounting studs are. This is an all black version of the popular 33 model a Tail Light. Yes this is a running Light and brake. ...(October 31st, 2018)
• 003953 Cycle Standard Model Tail Light Mounting Bracket Vertical 646418972326 (24.8% similar) Light mounting bracket only, Tail and license plate not included. This bracket is designed to mount a model Tail Light not included, as well bilateral b, c,and e Lights which fit license plate without provision for. 30 day money back guarantee free expert tech support we eat, sleep, live love ...(September 10th, 2018)
• 024qs Unbranded Smoked Led Tail Light Sequential Turn Signal 092624066333 (28.2% similar) The ground wire is same color used on both turn signals. Use the red connectors:place one wire inside along channel, place another other channel. The same way as a Light bulb flickers. If you are using the resistors, place one end of resistor in middle either channel along with wire. Connect the ...(April 2nd, 2018)
• 031 Smoke Lens Brake Tail Light For Suzuki Hayabusa 617949635585 (34.3% similar) Normally in 4 work day...(November 4th, 2018)
• 032018 Milne Nos Vintage Tail Light Lucas Style Bsa Triumph Norton (32.4% similar) Bazooka garage ships worldwide via us postal service. Nos vintage Milne Tail Light, Lucas style, 12 v for BSA triumph Norton harley chopper Bobbie new in the box, from 1960 S or 1970 S made japan. For a reasonable shipping quote. Global shipping available...(June 23rd, 2018)
• 032it Unbranded Clear Led Brake Tail Light Integrated Turn Signal For (23.4% similar) This is in good working order and comes with the rubber, but its not pictured...(June 25th, 2018)
• 033 Aftermarket Parts Operating Voltage Led Tail Light For 617949633079 (20.4% similar) Normally in 4 work day...(September 24th, 2018)
• 035 Tail Light For Suzuki Gsxr Sk 617949647663 (31.1% similar) Normally in 4 work day...(October 10th, 2018)
• 035a Mt-outlet1 Led Tail Light (18.9% similar) Part: MT-OUTLET1 prices...(May 6th, 2017)