What size are spark plug threads?

Threads. There are currently three spark plug thread diameter and pitch sizes used on motorcycles and ATVs: 10 mm x 1.0, 12 mm x 1.25 and 14 mm x 1.25. There are currently two thread reaches (lengths) used: 1/2 inch and 3/4 inch. Never use a spark plug of the wrong reach.

What thread is a 12mm spark plug?

Identifying NGK Spark Plugs

What thread is a 5’8 spark plug?

14mm
Spark Plugs – 14mm Spark Plug Thread Size – 5/8 in.

Are spark plug threads universal?

While you should buy spark plugs in matching sets for your vehicle, not all spark plugs are universal. Spark plugs come in different sizes with different gaps and are manufactured using a variety of metals. Finding the ones that you need can be difficult.

How do you determine spark plug thread size?

The thread size for Spark Plugs refers to the size of the threads that screw into the cylinder head. The first number is the diameter. The second number is the thread pitch….Some common thread sizes are:

1. M18 x 1.5.
2. M14 x 1.25.
3. M12 x 1.25.
4. M10 x 1.0.

Does spark plug thread length matter?

The engine will not operate properly without the proper thread reach. If a spark plug with the wrong thread length is erroneously used, the piston or valve could strike it and damage the engine. Ensure the spark plug has the correct projection dimensions.

What is the recommended spark plug gap?

Usually . 035″ is around the best gap, even though many instruction manuals say to open your gap to . 045″. Go ahead and try that, but when it doesn’t run as good, or it drops cylinders at high RPM because that wider / weaker spark can’t light the cylinders consistently, you’ll know why.

How do I choose the right spark plug?

At the auto supply store, don’t just ask a salesperson which type of plug you should buy — you have a very good chance of getting the wrong one. First look up the specifications yourself, and then ask for the plug by number. If you’re unsure, have a salesperson double-check it for you.

Which is better iridium or platinum spark plug?

Iridium is said to be six times harder and eight times stronger than platinum with a 700° higher melting point. Iridium spark plugs have extremely fine electrodes while retaining excellent wear characteristics. Thanks to its strength, iridium spark plugs can last up to 25% longer than comparable platinum spark plugs.

Do iridium spark plugs increase horsepower?

Increase your performance. Iridium plugs take less voltage to fire which results in more coil dwell time. That translates to better combustion, lower emissions, better fuel economy and more horsepower.

What does M14x1 25 mean?

The firing end of a spark plug threads into the cylinder head. A spark plugs threads are comprised of 3 dimensions: Reach, Diameter and Pitch. When a thread size is expressed in a set of two numbers, for example, 14×1. 25 or M14x1. 25 the first number is the thread diameter and the second number is the thread pitch.

How big is a Champion spark plug thread?

The second letter of the Champion spark plug code (in this case an “L”) indicates the thread size and reach of the spark plug. There are three size spark plug threads and two reaches currently being used in motorcycles and ATVs. “L” indicates a 14 mm x 1.25 pitch size with a 1/2″reach. “N” indicates a 14 mm x 1.25 with a 3/4″ reach.

What are the thread sizes for spark plugs?

Threads There are currently three spark plug thread diameter and pitch sizes used on motorcycles and ATVs: 10 mm x 1.0, 12 mm x 1.25 and 14 mm x 1.25. There are currently two thread reaches (lengths) used: 1/2 inch and 3/4 inch. Never use a spark plug of the wrong reach.

How big should the gap be on a spark plug?

If there is no number at the end of the spark plug code, it should be gapped to .7 mm or .028″ unless specified differently by the vehicle manufacturer. Here is an example of the Nippon Denso basic spark plug code.

What do the numbers mean on a spark plug?

“W” indicates a 14 mm x 1.25 pitch size, “X” indicates a 12 mm x 1.25 size and “U” indicates a 10 mm x 1.0 size. The number (24 in this example) indicates the heat range of the spark plug, the higher the number the colder the heat range.