white plugs, need some advise

[08FatBob]

I have an 08 Fat Bob and have modified the intake and exhaust as follows; a SE high flow A/C, Rush 2" baffle slip ons, and a V&H Fuelpak. I noticed the other day when putting on a set of headbolt covers, which calls for you to remove the plugs in order to properly hide the set screw, that the plugs appeared rather white which was an indication, to me anyway, of a lean running engine. It was my understanding the fuelpak was to richen up things. Should I be concerned?? Is there a fix?? any advise is greatly appreciated. As a footnote, I intend on calling V&H tomorrow to get their spin on it as well.

[PeterV]

Some info

clicky

[frisco-rigid]

Hey PeterV

Great link and super good info but not really applicable to our sickles..

One tip-off is the disclaimer --
VALID ONLY for full load acceleration or steady state dyno tests

You'll notice the plugs shown are very "cold" plugs used in their racing machines, not like the fairly hot plugs we use in our sickles for mostly low RPM riding..

08fat
Remember, having a new sickle you might (I hope not) have a difficult time getting a shop to adjust things for good running.. The Pinko-Commie EPA has dictated what your A/F mix should be and alotta shops are concerned about getting fined if they mess with it.. When you saw the color of the plugs it was a snap-shot of the mixture/condition after idling.. Sounds lean to me too.. I've read that from EVO's on up they're suppose to run better lean,,, I just simply don't believe that.. My experience only..
Get out on the highway, stay at a comfortable speed for about 10 -15 minutes,, do not flucuate RPM's.. When ready, IN ONE MOTION, pull in clutch and switch off ignition and coast only (do not shift) to safe place..
Gloves on plugs out and look at color.. If still bone white it's lean,, if grey or kinda brown (my preference) you're good.. On the way home, repeat test on frontage road if available, at slower lower RPM speed, say 35-45, don't flucuate, pull plugs and read.. You will see a snapshot of the A/F mix at those RPM's..
It's EFI huh,, well, to change the mixture you gotta have a shop with the correct computer/flash/map crap do it for you..
EFI on HD's--- another step on the downward spiral in our motor world..

[PeterV]

Yo frisco,

Yep, them are plugs used for track. But there's still lots to be learned from that site IMHO.
The base ring is the indicator for jetting, whether it's track or street.
Ditto for the strap as the indicator for temp.
And the porcelain.....ahh yes, the porcelain. Some will be coffee colored, some brown, red, etc etc...all those additives in the different makes of gas, that's where they show up. Anyone remember the first set of plugs they pulled from their brand new, hasn't been tinkered yet ride? I bet there was some head scratching....
But to be sure, "white porcelain=running lean" that's not an accurate statement.

I've trusted the base ring method of plug reading for many years. And the times my bikes have been on a dyno, the AFR graphs confirm what I see on the base ring of a plug.

I'm not throwing a wrench in the works here...Just an opinion of what works for me, thought I'd pass it along.

...and a beer comin your way frisco.

[08FatBob]

thanks for the weigh ins guys, i do appreciate it. With this being my first bike and being brand new under warranty, even doing the mods kinda freaked me out, worrying about the warranty. Then when I saw the plugs, I about pooped myself and knew these HD forums would be the best place for advice so thanks again. Frisco, I will definately try your suggested method of reading the plugs, hopefully this weekend, and will let you know. I'll do my best to maybe get some pics too so you can see what I'm seein.

[frisco-rigid]

Hey 08

Good luck and have fun.. When you do these these things for yourself it will become fun.. Yeah baby..

Hey Pete

Thanks for the beer, it's something that could happen one day..

What a superb reply.. It is our own experience that should always be the basis for our answers.. Mine is just simply diff from yours..
I do use primarily the porcelain to read my plugs.. I see virtually the same color on the ground and electrode..
And similar to you, I have done dyno "mixture" runs, (just normal shifting through gears to the equivalent of highway speed) and been right-on..
Yeah daddy..!

[08FatBob]

frisco, just got my hands on an 08 dyna service manual and now am very comfortable with things. The service manual has four picutres of plugs, three of which show symptoms of an improperly running motor. The fourth photo shows a plug from a "balanced combustion" motor which is just what mine looks like. It also states that a white, tan or light brownish colored plug indicates balanced combustion. That said, I'm much more comfortable now with my current engine situation. I still wanna try what you suggested just to see what it shows. Will let you know. Thanks again.

This winter my pumped FXR4 (SE heads, 10.5:1 cr. ,SE 57 cam, Mikuni 42, V&H 2 into 2 Hot Shot pipes, SE ign. module) started hesitating and backfiring a bit (mostly just off idle) so I decided to pull the plugs and look for evidence.

The plugs, which were put in long before I bought the bike, were Harley SE TP12P platinums which I think are colder than what're called out for a stock FXR and are normally used on Sportsters. The rear plug was definitely cleaner and whiter all around while the front plug's insulator had that light tan I thought I wanted to see. The electrode on the front plug, however, looked ever so slightly loaded up but it was hardly noticable at all. The questions in my mind were, "Is the timing alright? Is the carb leaned out from an air leak in the intake manifold? Or, does it just need new plugs?"

I always fight the urge to just start changing parts when there is an ellusive problem. Vanity I guess but wild guess parts swapping can get expensive and humbling real fast. Still, I figured it was probably time to change the plugs anyway as part of my winter bringing everything up to snuff maintenance project. When I bought new plugs (same SE TP12P's) the problem went away and the bike was back to its old rip snortin' self.

So here's my lessons learned in this little trip:

1) Though the electrodes and insulators looked pretty good one of the plugs was obviously fouled a bit but it wasn't obvious to the naked eye. I had encountered this back in the day when I tuned my own flat track bikes. I found then you could have a plug that looked perfectly fine to the naked eye and had little use but it could still be responsible for some popping under load.

2) The base of the old plugs was dark black in both cases. I now attribute this to worn valve guides. The engine build has 29k on it and I believe the guides and seals are worn because I have observed that when the bike has sat for an hour or so you can see and smell a small but distinct puff of blue oil smoke coming out of the pipes on start up. I don't think the black base is from rich jetting in this case as the site Peter turned us on to would suggest. In this case I think the cause of the black base is oil burning. If the engine build was fresh I would defintely look to jetting issues if the plug base were black however.