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SigmasTek  |  SKU: BW-18090

STX20L-BS Battery for Harley FLS Softail S Fat Boy S 2016-2017 High Performance

Sale price $59.98 USD Regular price $82.13
Shipping calculated at checkout.

➤ Direct replacement for OEM battery ensures hassle-free installation

➤ Guaranteed fit for 2016-2017 Harley FLS Softail S and Fat Boy S models

➤ Maintenance-free design saves time and reduces upkeep

➤ High Cold Cranking Amps (CCA) delivers reliable starting power

➤ Superior vibration resistance and spill-proof construction enhance durability


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

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Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 18 Ah

Terminal Type

Nut & Bolt

STX20L-BS Battery for Harley FLS Softail S & Fat Boy S (2016-2017)

The STX20L-BS is a direct-fit, maintenance-free replacement battery engineered for Harley FLS Softail S and Fat Boy S models (2016-2017) with the 110 engine. Built to meet or exceed OEM specifications, this high-performance battery provides the reliable starting power and vibration resistance modern riders expect. If you need a dependable, long-lasting battery that fits your Harley perfectly, the STX20L-BS delivers pro-level starting capability and robust construction.

Key Specifications

  • Model: STX20L-BS
  • Compatible Models: Harley FLS Softail S, Fat Boy S (2016-2017) with 110 engine
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 18 Ah
  • Terminal Type: Nut & Bolt
  • Maintenance: Maintenance-Free Technology
  • Design: Spill-proof and Leak-proof
  • Starting Performance: High CCA for reliable starting power
  • Vibration Resistance: Superior vibration resistance for heavy-duty riding
  • Fitment: Direct replacement for OEM battery

Benefits

The STX20L-BS replacement battery is engineered for rugged motorcycle use, delivering the durability and starting torque riders depend on. As a high-performance battery with superior vibration resistance, it holds up to rough roads, strong engines, and extended idle or accessory loads. The spill-proof design and maintenance-free operation reduce upkeep, letting you focus on riding instead of battery maintenance.

This unit offers the consistent cranking power required for large-displacement engines, making it an ideal choice for Harley models with demanding electrical systems. Its nut-and-bolt terminals provide secure, vibration-resistant connections for long-term reliability. Because it’s a maintenance-free replacement battery designed to match OEM fit and function, installation is straightforward and worry-free.

Typical applications include motorcycle starting systems, touring bikes with heavy electrical loads, and any scenario where a long-lasting battery and dependable cold-cranking ability are needed. Riders seeking a high-quality, long-lasting battery will find the STX20L-BS combines ease of use, proven performance, and durable construction.

Ready to ride with confidence? Order the STX20L-BS replacement battery for your Harley FLS Softail S or Fat Boy S (2016-2017) today and experience reliable starts, superior vibration resistance, and maintenance-free performance.


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