Spark Plug (NGK D8HA) | Honda CB175 / CL175 / SL175

Description

Spark Plug (NGK D8HA) | Honda CB175 / CL175 / SL175

The NGK D8HA is the factory-correct spark plug for the CB175, CL175, and SL175. A fouled or worn plug shows up as a misfire, hard starting, or a cylinder that won’t pull its weight. Fresh plugs give your ignition a clean, hot spark to work with.

Why You Need This

The D8HA is the correct heat range for these engines: hot enough to burn off deposits, not so hot it pre-ignites. Run a plug that’s too cold and it fouls with carbon; too hot and it can pre-ignite. The copper-core construction gives a reliable spark and a long service life.

The CB175 family is a parallel twin, so you need two plugs, one per cylinder. When you’re chasing a carb jetting issue, grab a few extra and read the porcelain tip color to dial in the mixture.

Specifications

Note: The CB200 and CL200 are based on the CB175 but use a different spark plug, the NGK D8EA. Don’t substitute the D8HA on a CB200 or CL200.

Installation

Difficulty: Beginner

Tools needed: 18 mm spark plug socket, gap gauge

1. These plugs ship with a screw-on terminal nut. If your plug cap uses a bare stud, unscrew the terminal nut first so the cap seats.
2. Check the gap with a gauge and set it to 0.024–0.028″ by bending only the outer ground electrode.
3. Put a dab of light oil on the threads and thread the plug in by hand to avoid cross-threading.
4. Tighten until snug. Don’t overtighten.