The Truth About Spark Plugs Please

[Larry64]

The "truth" about spark plugs is...

They spark.

There ya go.

Seriously tho, I run the stock plugs and I put a lot of miles on em. They look great when I change them but I do notice an immediate difference with a new set. I have trioed NGK, and others and always wind up back at the Stock oem plug. Which I understand is made by Champion. The difference between the OEM and Champion  RA8HC ? The feral on top that your wire snaps to. Unless they have changed them, the feral on the  RA8HC can unscrew. OEM does not. Some folks ( ) like to take a pair of dykes and lightly mung up a couple of threads and then screw the feral back on. This keeps the feral from loosening which cause issues.

My bike is an 05 bumped up to 95ci, cam changed, non stock exhaust, heads mildly worked and it seems to prefer plain ol OEM or Champion plugs. Everything else just seems to cause a problem at some point or is just a waste of $. YMMV.

  OK, I had that coming....

[Tsani]

The "truth" about spark plugs is...

They spark.

There ya go.

Seriously tho, I run the stock plugs and I put a lot of miles on em. They look great when I change them but I do notice an immediate difference with a new set. I have trioed NGK, and others and always wind up back at the Stock oem plug. Which I understand is made by Champion. The difference between the OEM and Champion  RA8HC ? The feral on top that your wire snaps to. Unless they have changed them, the feral on the  RA8HC can unscrew. OEM does not. Some folks ( ) like to take a pair of dykes and lightly mung up a couple of threads and then screw the feral back on. This keeps the feral from loosening which cause issues.

My bike is an 05 bumped up to 95ci, cam changed, non stock exhaust, heads mildly worked and it seems to prefer plain ol OEM or Champion plugs. Everything else just seems to cause a problem at some point or is just a waste of $. YMMV.

  OK, I had that coming....

Glad to help

[N-gin]

Iridium, platinum, waste of money

Get regular copper spark plugs.
I run vRod NGK plugs. Sometimes with the v-NGK. Burn nice, heat range is spot on.
Champion truck plugs were really good I thought but none seems to know where they went.

[smoserx1]

Twice I had the stock 6R12 plugs foul.  Each time it was just one plug at a time, and what had happened was a small piece of dry carbon had become stuck between the electrode and the ground  Nothing on the bike was wrong or needed any maintenance, it was just a fluke thing.  Easily cleaned off by a piece of cardboard like a business card.  In both cases it was immediate, I could tell instantly something was wrong.  Now this was not a real problem by any stretch of the imagination, but it was a hassle to me.  And it is for this reason alone I have gone to fine wire plugs.  There is simply less chance of this happening because of the smaller center electrode, and it has not happened to me since.  Been using them for about 75000 miles now.  I don't have an ion sensing ignition so I am not going to get any code from the wrong plug.  These plugs do not start  any easier, get any better MPG or increase performance that I can tell, but they don't foul.

[FlaHeatWave]

Buy the RA8HC from the parts store.   Same plug as the OEM.   

Yes, the RA8HC, also know as Champion 810C won't throw codes and works fine. Do unscrew the cap and bugger the threads a little then screw the cap back on. This way the cap can't unscrew and get loose.

'Been running the RA8HCs for years set at 0.40 in stock / modded HDs,,, same plug as OEM, never an issue,,, used to bugger the threads but the last 2 sets of RA8HCs the cap was solid on the plug   about $2.50 ea at wally world.

Don't forget the anti-seize...