Wrong spark plugs for 03 fxst?

[quickster]

When I changed the plugs I noticed that the old plugs were Champion RA8HC instead of HD-6R12. Is there any difference. Bike seemed to run pretty good, but someone riding behind could smell gas coming from my bike. The tank was not full causing overflow. Has the SE carb upgrade with the SE pipes.

[ViennaHog]

Originally Posted by quickster

When I changed the plugs I noticed that the old plugs were Champion RA8HC instead of HD-6R12. Is there any difference. Bike seemed to run pretty good, but someone riding behind could smell gas coming from my bike. The tank was not full causing overflow. Has the SE carb upgrade with the SE pipes.

The RA8HC is the equivalent of the HD plug. There mayby small differences in the insulator set up, but nothing that will cause a fuel smell.

[murphdog]

VH is correct, RA8HC is the Champion equal to 6R12. I've run the Champions and they work fine. They come pre-gapped way less than 0.040" though, so getting the ground strap perpendicular to the center electrode at 0.040" is tough. There's no good reason I know of not to use 6R12's.

[HDMD88]

Originally Posted by murphdog

VH is correct, RA8HC is the Champion equal to 6R12. I've run the Champions and they work fine. They come pre-gapped way less than 0.040" though, so getting the ground strap perpendicular to the center electrode at 0.040" is tough. There's no good reason I know of not to use 6R12's.

There is a difference between air cooled plugs and water cooled plugs. The difference is under the crimped metal bezal where the ceramic top meets the metal. There are tiny little ceramic balls under the bezal, on an air cooled plug there are less ceramic balls to let the plug expand without cracking the plug causing a miss fire. The Champion plug is the same heat range and all but there are lots more of the ceramic balls so the expansion rate is limited. If you installed a HD plug in a car and ran it for a while you would see signs of oil and fuel residue on the ceramic at the bezal.
Just a foot note for your knowledge.

[murphdog]

I guess I didn't realize that Champion plugs are "water cooled plugs". For what it's worth, RA8HC is the correct Champion plug for twin cams and I never had one crack.
I hadn't actually considered putting H-D plugs in my car, but thanks for the tip.

[HDMD88]

Originally Posted by murphdog

I guess I didn't realize that Champion plugs are "water cooled plugs". For what it's worth, RA8HC is the correct Champion plug for twin cams and I never had one crack.
I hadn't actually considered putting H-D plugs in my car, but thanks for the tip.

Water cooled vs. air cooled....car vs. bike thats the best compairson I could come up with.
Champions makes the HD plug BTW.
Look you didn't know the difference and I just told you there is a difference accept it or not thats up to you but if your giving me crap over it or being rude simply put me on your ignore list.......

[murphdog]

Originally Posted by hdmd88

Water cooled vs. air cooled....car vs. bike thats the best compairson I could come up with.
Champions makes the HD plug BTW.
Look you didn't know the difference and I just told you there is a difference accept it or not thats up to you but if your giving me crap over it or being rude simply put me on your ignore list.......

Didn't know the difference between what??? Did I say it's OK to use car plugs in a motorcycle, or "water cooled plugs" in an air cooled motor??? I don't believe you know me well enough to assume what I do and don't know. I simply backed up ViennaHog's comment that the RA8HC is the Champion equal to H-D 6R12. Is the RA8HC a car plug? Look up applications for it on Champion's website, one automotive application and about 10,000 (exaggeration) motorcycle and ATV applications...yes, some of the motorcycles and ATVs are liquid cooled. I figure Champion has been in business for awhile and probably has a couple of good engineers that know how to design spark plugs for a given application. If they say the RA8HC is what works in a twin cam motor, I believe them. I'm not promoting Champion plugs or any other plug, in fact if you look back in my original post you'll see that I said "There's no good reason I know of not to use 6R12's."
No disrespect for you intended, just don't come out of the blue and tell me what I don't know.
P.S. I'll be destroying one each used 6R12 and RA8HC spark plugs tonight in search of tiny ceramic balls.

[ViennaHog]

Originally Posted by murphdog

P.S. I'll be destroying one each used 6R12 and RA8HC spark plugs tonight in search of tiny ceramic balls.

Don't bust your balls

[HDMD88]

Originally Posted by murphdog

Didn't know the difference between what??? Did I say it's OK to use car plugs in a motorcycle, or "water cooled plugs" in an air cooled motor??? I don't believe you know me well enough to assume what I do and don't know. I simply backed up ViennaHog's comment that the RA8HC is the Champion equal to H-D 6R12. Is the RA8HC a car plug? Look up applications for it on Champion's website, one automotive application and about 10,000 (exaggeration) motorcycle and ATV applications...yes, some of the motorcycles and ATVs are liquid cooled. I figure Champion has been in business for awhile and probably has a couple of good engineers that know how to design spark plugs for a given application. If they say the RA8HC is what works in a twin cam motor, I believe them. I'm not promoting Champion plugs or any other plug, in fact if you look back in my original post you'll see that I said "There's no good reason I know of not to use 6R12's."
No disrespect for you intended, just don't come out of the blue and tell me what I don't know.
P.S. I'll be destroying one each used 6R12 and RA8HC spark plugs tonight in search of tiny ceramic balls.

Your right Murphdog I don't know you, in fact I don't care to ever get to know you. If my statment of the plugs differences offended you too bad, grow up.

[csoday]

Originally Posted by murphdog

P.S. I'll be destroying one each used 6R12 and RA8HC spark plugs tonight in search of tiny ceramic balls.

And when you see what Doc was telling you was right, don't forget to appologize to him. As he stated there are other things to consider besides heat range. And if in fact they do crack because of his given reason, that would explain the gas smell. Maybe we all learned something by his post.

[murphdog]

Originally Posted by csoday

And when you see what Doc was telling you was right, don't forget to appologize to him. As he stated there are other things to consider besides heat range. And if in fact they do crack because of his given reason, that would explain the gas smell. Maybe we all learned something by his post.

Apologize for what? The original poster on this thread was asking if Champion RA8HC plugs were the wrong ones for his '03 FXST, I said that they are the correct plug. If you don't agree with that, go to Champion's website and look it up. I've used them and didn't have any problem. If you or anybody else has had problems with them cracking, I'm sorry about that. Take it up with Champion, not me, maybe they would like to know that it's not really the correct plug. I don't appreciate the implication that I'm stupid because I don't know the difference between "air cooled" plugs and "water cooled" plugs. I could care less what the difference is. If Harley says use a 6R12 or Champion says use an RA8HC, then that's what I'll use. If Dodge said to use Harley plugs in my car, I probably would. But they don't, so I won't.
The original poster also said "Bike seemed to run pretty good". HDMD reported that "on an air cooled plug there are less ceramic balls to let the plug expand without cracking the plug causing a miss fire." Wouldn't one think that a cracked plug causing a miss fire would not be considered to "run pretty good?"

[wyodude]

Originally Posted by murphdog

I don't appreciate the implication that I'm stupid because I don't know the difference between "air cooled" plugs and "water cooled" plugs. I could care less what the difference is.

What doc meant was plugs used in water cooled engines as opposed to air cooled engines. And you damned well know what he meant.

What you need to apologize for is going off on a respected member of these forums without provocation. Doc has given freely of his time and knowledge on these forums and helped a lot of people.

We've lost too many knowledgeable members because they get tired of bullsh!t just like this.

regards,

wyo

[murphdog]

You're right, I did know what he meant. I also know that the RA8HC is the correct Champion plug for air cooled Twin Cam motors. I believe the implication was that the Champion RA8HC plug was not the correct plug because it is for water cooled car engines. That is quite simply wrong, respected member or not.
There was no need for the condescending explanation of the difference between air cooled and water cooled plugs when the Champion plug in question is, in fact, an "air cooled" plug or the comment about a footnote for my knowledge.
Look you didn't know the difference and I just told you there is a difference accept it or not thats up to you but if your giving me crap over it or being rude simply put me on your ignore list.......
I consider that to be provocation.

[HDMD88]

This isn't the first time Murphdog and I had a dispute....I don't need an apology from him nor do I want one from him. I take his kind with a grain of salt....They know too much to learn anything else...all we can do is pray for people like him, and he should thank God I do that for him.

[csoday]

A cracked plug MAY misfire if the electrode lead is broken. If the it is cracked but the lead is not broken it may seem to run fine while still allowing some of the mixture to escape allowing his friends behind him to SMELL GAS.

Did you count your balls yet.