Harley-Davidson M125 Spark Plug
The Harley-Davidson M125 (125cc) takes an NGK BR7HS-10 spark plug, gapped to 0.024".
Key takeaways
- Spark plug: NGK BR7HS-10.
- Iridium upgrade: NGK BR7HIX.
- Gap: 0.024 inch - set it before fitting.
- Covers 1979-1985.
Buy the plugs for your Harley-Davidson M125
The standard plug is the exact-fit replacement. The iridium version drops into the same spot, lasts longer, and fires a little stronger for a few dollars more. Many engines take more than one - check how many cylinders you have.
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Frequently asked
What spark plug does a Harley-Davidson M125 take?
The Harley-Davidson M125 takes an NGK BR7HS-10 spark plug, gapped to 0.024 inch. The iridium upgrade is the BR7HIX.
What is the spark plug gap for a Harley-Davidson M125?
The spark plug gap for the Harley-Davidson M125 is 0.024 inch. Check and set the gap before fitting a new plug - most powersports plugs need a small adjustment out of the box.
Can I use an iridium plug in a Harley-Davidson M125?
Yes. The BR7HIX is the iridium version of the BR7HS-10 - same fit, longer life, and a slightly stronger spark. It is a straight upgrade.
More parts for your Harley-Davidson M125
We cover the other consumables for your machine too - the exact fit, cited, in one place.