Yamaha YZ400 Spark Plug

The Yamaha YZ400 takes an NGK BPR7ES spark plug, gapped to 0.028".

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Key takeaways

  • Spark plug: NGK BPR7ES.
  • Iridium upgrade: NGK DR8EIX.
  • Gap: 0.028 inch - set it before fitting.
  • Covers 1980-1981.
Standard PlugBPR7ES
Iridium UpgradeDR8EIX
Gap0.028"
Verified fitLast checked
Reviewed by the CrankDex editorial team against manufacturer and retailer fitment data.

Buy the plugs for your Yamaha YZ400

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 Yamaha YZ400 take?

The Yamaha YZ400 takes an NGK BPR7ES spark plug, gapped to 0.028 inch. The iridium upgrade is the DR8EIX.

What is the spark plug gap for a Yamaha YZ400?

The spark plug gap for the Yamaha YZ400 is 0.028 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 Yamaha YZ400?

Yes. The DR8EIX is the iridium version of the BPR7ES - same fit, longer life, and a slightly stronger spark. It is a straight upgrade.

More parts for your Yamaha YZ400

We cover the other consumables for your machine too - the exact fit, cited, in one place.

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