Spark plug gapping

[Ryan314]

Is it neccassary to gap your spark plugs before installing them? Or do they usualy come gapped correctly already?

 

[IndyMX]

Is it neccassary to gap your spark plugs before installing them? Or do they usualy come gapped correctly already?

Even if they come gapped correctly, it's never a bad idea to check them before installing in your bike. Never know what may have happened during shipping.

 

[mandark1967]

Let's put it this way...

It's safer to check the gap than it is to rebuild a top end from the plug hitting the piston :)

 

[76GMC1500]

Let's put it this way...

It's safer to check the gap than it is to rebuild a top end from the plug hitting the piston :)

I think there is a little more clearance between the plug in the piston than that. An improper gap will make the plug prone to fouling or unable to light the fuel off during times of high cylinder pressures. It isn't necessary to gap the plug, if the gap is correct. Nowadays, the consistency of plug gaps is pretty good. But, you should still check it.