Atesilor 10.4mm Spark Plug Wires for Harley Dyna & Softail 1999–2017, Black OEM-Fit Heat-Resistant

Atesilor 10.4mm spark plug wires are a direct-fit replacement set designed to restore reliable ignition on Harley-Davidson Dyna and Softail models from 1999–2017.

If your Harley is showing hard-starting, misfires, or erratic idle, worn or damaged plug wires are a common, easy-to-replace cause. These Atesilor wires are molded to OEM dimensions, use heat-resistant rubber construction, and come in two lengths to match the factory routing so you can swap them in without cutting or reworking. The black finish keeps a clean, factory look while insulating the high-voltage conductor beneath.

Will these wires fit my specific Harley model?

They are manufactured to match OEM geometry for many Big Twin Dyna and Softail variants across model years 1999–2017. Use the part finder or verify OE part number DYNA-409BK against your bike to confirm fit before buying.

• Packed lengths: one 5.7" and one 17.7" wire to replicate factory routing.
• Designed for Dyna Super Glide, Wide Glide, Low Rider (2000–2017).
• Compatible with Softail Springer, Slim, Deluxe, Deuce (1999–2017).
• Built to OEM 10.4mm end diameter for direct connection to stock boots.

How do Atesilor wires perform under riding conditions?

These wires use high-temperature rubber that resists heat soak from the engine and exhaust, helping preserve insulation and maintain voltage transfer under load. While not a performance race wire, they offer dependable day-to-day ignition reliability for street and touring use.

• Heat-resistant rubber construction for sustained service around the engine.
• 10.4mm molded ends for consistent electrical contact and reduced leakage.
• Black sleeve that resists grime and blends with the bike’s aesthetic.
• Designed to limit arcing and minimize electromagnetic interference.

How simple is the installation and what should I check first?

Installation is straightforward: match each wire length to the factory routing and attach the molded ends to the original connectors and spark plugs. Inspect boots and terminals on the bike for corrosion or damage and clean contact surfaces before installing the new wires.

• No trimming required—comes with two pre-cut lengths to match stock layout.
• Confirm clean, corrosion-free mating surfaces on spark plug and coil ends.
• Replace one wire at a time to keep firing order and routing correct.
• Use dielectric grease on boots if desired for moisture protection.

When should I replace my spark plug wires?

Replace wires if you notice hard starting, misfires, engine hesitation, visible cracking, or if insulation is brittle from heat exposure. Regular inspection as part of seasonal maintenance helps prevent ignition issues while on the road.

• Signs: cracking, glazing, visible wear, or arcing marks on the insulation.
• Performance cues: rough idle, misfires under throttle, or longer crank times.
• Recommended: inspect wires each service interval and replace if aged.
• Replacing the set restores proper voltage delivery to spark plugs.

Who is this for: Riders and mechanics restoring or maintaining Harley-Davidson Dyna and Softail bikes from the 1999–2017 era who want an OEM-dimension replacement wire set that’s simple to install, resists heat, and preserves a black factory look. Ideal for owners troubleshooting ignition-related starting and running problems or anyone refreshing the ignition system without altering stock routing or aesthetics.