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SigmasTek  |  SKU: BW-18090

STX20L-BS Battery for Harley FLS Softail S Fat Boy S 2016-2017 High Performance 11.62 lb

25% off
Sale price $75.99 USD Regular price $101.99
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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
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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

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


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.

Technical Specifications

Voltage12 Volts
Amp Hours18 Ah
Terminal TypeNut & Bolt
Cold Cranking Amps (CCA)270
Length (in.)6.89
Width (in.)3.43
Height (in.)6.14
Weight (lb.)11.61

Product Highlights

  • Manufacturer: SigmasTek
  • Product Type: Powersport Batteries
  • Warranty: 6 Months
  • Bulk Orders: sales@batteryweb.com

Connections & Interface

  • Polarity: "'-/+"

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