Hey all, I'm looking at my plugs today, BPR5ES and it dawns on me that there is a carbon signature up into the threads about a 1/4". So, I say to myself..."Self, I can't believe you didn't notice this before"... I know I'm using the correct plug but it appears that it is extending into the chamber.

My question is this, has anyone ever tried the standard 1/2" thread plugs? They look like they would be a better fit than the 3/4" thread range.

 

I think it would probably run like ***** because the plugs would be masked by the thread recess.

Do your plugs have gasket rings on them?

 

Gasket rings? Yeah, they got em.

 

yes they need the gaskets rings , S&S other the little carbon build up are you plugs working good ?

 

Yeah, cowboy, they're working fine, it was just an observation...and a pondering! I might throw the standard plugs in just to see what happens but I thought it wise to think outloud first

 

I thought it wise to think outloud first I use to do it but got wise after awhile when the wife kept saying shut up , which bike it the pic is yours? as for carbon build up ,I would also try the stock plugs just to see how they work

 

The 'STC is mine, the chopper belongs to one of my buddies. I prefer NGK to Champion which is why I'm using the plugs I am. As to the carboned up threads, I think it will be the same with any 3/4" plug, wouldn't it?

 

I like NGK plugs too, I run them in the 80" fxst and the sporty with no problems.
Ran a set in the 111 S&S for a little while until I realized they protrude into the chamber almost one thread.
The problem there is the carbon on the protruding thread can damage the threads on the head when the plug is removed.
Compared them side by side to the recommended ra8hc Champions, and sure enough, the NGK was just a little longer.

 

Hmm, that's interesting, maybe I'll get a set of Champions and check the thread length.

 

I use the autolite platinum 4265 plug. I have not seen this with this plug, but I do index them. On a few over the years I have installed they indexed
perfect without a shim. When removed no soot on the threads. If you index remove the crush washer and place it between shim and head.