Just as a point of interest. When I left for SD M3 put in a new set on HD Gold Plugs. On returning he checked the plugs and the rear cylinder runs so hot that the plating was burned off.

 

I went a couple heat numbers lower also to get some more cooling but the electrodes were smaller "Champion Plugs" front cylinder plug darkened up some, the rear is still chalky white! The XIED's should have richined up the AFR the same to both cylinders but the rear still looks lean and hot!

I am definately going to a fuel management sytem that will let me adjust the AFR for each cylinder individually, have not had time to study the TTS but was hoping that one would allow for that! Maybe M3 or Wizard will speak to that!

That is why I am waiting for winter to finish my mods on the Tri, looking for the best fuel management system and the one that will let me control more variables.

 

After a 1300 mile road trip in high outside temps, my rear cylinder plug ceramic had a nice tan hue. However, I was sucking in a certain amount of blow-by oil to be burned. But I'm not sure what effect that would have on the plug color.

 

I was referring to the gold plating on the outside of the plug.

 

Gold being a good conductor I can see it being used for plugs, NASA uses it on most their contacts used in space electronics. Maybe it was the melting temp of the material they plated with or the bonding agent. That rear cylinder gets hot, we all know that.

I was just commenting how the front cylinder seemed to get some cooling effect from the AFR being richined up but the rear did not, or at least not enough. The 02 sensors are even better looking!

Was that a Harley plug? I would like to know what the plug manufacturer says about their coating coming off and see if they can side step as slick as Harley does or if they actually look at the problem.

It would be great if we could get a plug manufacturer to verify what we already know about the heat, especially in the rear cylinder. I imagine the plug had some kind of warranty?

I believe Champion makes the OEM plugs for Harley! Will be interesting to know who makes the gold plated ones!

 

If your looking for a fuel management system that will let you control more variables that would be TTS. Sometime when you get chance you can download the manual for the TTS and read all about it from their site http://www.mastertune.net/files/Tuni..._Guide-126.pdf.

 

Thanks, I will read this. I have been leaning toward this one and I think I may have found a place to get a good dyno tune. The guy uses this system. I am going to wait until winter so I can change the cams and run them in before I get it dyno'd. It has been to hot to even think about wrenching down here!

Plus we get our bi annual floods and am still digging out!

 

No need to run in the cams, their roller. You might have cringed if you seen how the build on my 06 Ultra was broken in. I put it on a dyno immediately where the operator broke it in then he proceded to work on the tune. Interesting listening to an engine with less than 25 miles on it getting the crap whipped out of it when they make a full pull.

 

Well another myth debunked, thats good to here! I believe I will go get a cup of coffee when they do the dyno! I get nervous just warming it up.

Thanks

 

Not to oversimplify things....and I wish all you folks good luck in trying to bring down the rear jug heat via tuning, but for as long as I have owned an air-cooled v-twin the rear cylinder has always ran hotter. BMW sticks both jugs out in the wind....we stick the rear jug right behind an obstacle...called the front jug. Just for curiosities sake...take a look around the next big group of Harleys you run across and look at the area around the plug on top of the rear head. If it was originally black, a well worn TC will be polished around the plug area on the rear cylinder where the finish has been burned off.