Fine tuning spark plug gap By jjoshua20213 (Read 533 times)

[jjoshua20213]

So I know the gap for a 139qmb is .023-.030 and some people say .035 works best

But with the plug removed and placed in the boot I can visually see spark.

My question is would I be able to adjust the gap and visually look for a bigger or better looking spark and adjust accordingly?

[trashtruck12172]

please tell me that I'm reading this wrong and you're not actually planning on adjusting spark gap with it firing?

[cyborg]

it can be done ,,but the gains are marginal,,,better to set in the middle of the range and use indexing washers under the plug to make the gap orientation to the middle of the combustion chamber

[jjoshua20213]

Jul 20, 2015 6:09:16 GMT -6 trashtruck12172 said:

please tell me that I'm reading this wrong and you're not actually planning on adjusting spark gap with it firing?

You read it wrong

[jjoshua20213]

Jul 20, 2015 7:50:42 GMT -6 cyborg said:

it can be done ,,but the gains are marginal,,,better to set in the middle of the range and use indexing washers under the plug to make the gap orientation to the middle of the combustion chamber

Yea, I figured the gains would be little. I plan on changing everything on the ignition system. (Thicker wires, better boot cap, ect.)

My favorite performance cdi went out the other day and i'm sure it was stressed due to poor ignition components.
Never had a problem on any other bike until I put it in this one.

Also a super strong spark makes carb tuning easier as the engine responds quicker to adjustments.

[Alleyoop]

Best thing you can do for a better spark easier starting etc.. is put in a IRIDIUM PLUG.
Alleyoop

[jjoshua20213]

I have those. Ive been trying to see if the cr7hix is better vs. the cr8hix. The bbk raises compression and heat by alot.