Changing Spark Plugs on a BMW DOHC Boxer Engine

2026-03-16 - on a BMW Motorcycle

Hello everyone! Welcome to Hornig – today we're focusing on the heartbeat of your boxer engine: the spark plugs.

 

What you'll need: New spark plugs, the correct spark plug wrench, and, very importantly, our ignition coil puller. You'll also need a torque wrench and pliers.

 

Changing the spark plugs is crucial for the smooth running and performance of your BMW. Before we begin, here's the most important tip: The engine should be cold or only lukewarm!

 

When the engine is warm, it expands, making it difficult or even impossible to change the spark plugs without damaging them. Safety first!

 

We'll start with the main spark plug. First, remove the ignition coil cover and disconnect the cable.

 

To remove the ignition coil more easily and without damaging it, use our ignition coil puller along with a pair of pliers. This will allow you to remove the coil cleanly and safely.

 

The spark plug is now exposed. Take your spark plug wrench and carefully loosen the plug. Then, carefully remove it with pliers.

 

Now for the secondary spark plug. To access it, you must first remove the cylinder head cover and then the ignition cable.

 

The secondary spark plug is removed in the same way as the main spark plug: loosen it and carefully pull it out.

 

Now it's time to install the new spark plugs. Insert them carefully – never at an angle! – and then tighten them to the correct torque.

 

The secondary spark plug is now removed in the same way as the main spark plug: loosen it, then carefully pull it out. Once everything is secure, the fairing parts, ignition cable, and ignition coil cover are reinstalled in reverse order.

 

That's it! Your boxer engine is now ready for thousands more miles. You can find the right tools and spark plugs in our shop, of course.

 

Do you have any questions? Leave them in the comments and visit our shop for more DIY tips and high-quality accessories. Cheers, see you in the next video!

 

Link to spark plugs: https://www.motorcycleparts-hornig.com/Search.html?q=spark+plug

Link to ignition coil puller: https://www.motorcycleparts-hornig.com/Search.html?q=ignition+coil+puller

Back to news