Iridium spark plugs?

[650mark]

Any downside to these in my '80 xs1100 special? Besides the cost?
Problems with ignition systems? thanks

[natemoen]

Well, I would at least sayake sure you have her running in tip top shape before you put them In.

I don't like them.in these old engines...

[650mark]

a: runs great
b:why?

[WMarshy]

Any downside to these in my '80 xs1100 special? Besides the cost?
Problems with ignition systems? thanks

Yeah, cost...

[TopCatGr58]

Hey Mark,

This is curious, I was doing a search and found a similar thread started by you in July, 2012. Here's the link to a thread with good info on the iridiums that I posted in your first thread, but it's still applicable.

http://www.xs11.com/forum/showthread.php?t=36533&highlight=iridium+plugs

One of the points I got from Ddragon's comments were that they provide a stronger spark with less Coil energy because of the smaller core tip vs. copper core style. But with regards to Nate's comments, if the engine isn't tuned properly ie. too rich, or has weak rings and burns a little oil, because of the smaller spacing, they can foul easier. I didn't re-read it enough to see if they can be cleaned like standard plugs.

But because I run the hi output coils, I get a nice strong spark with just standard inexpensive plugs....I even run Champion without any problems. But for folks with the "weak" OEM coils, they report that they have easier starting and stronger running, etc.! YMMV

T.C.

[kflyboy]

Iridium plugs

I have a set of the iridium plugs. Will they work right with the ngk resistor caps? I am assuming 10k ohms resistance. If not, where do I get the non-resistor plug caps? The coils on my bike are originals.

[650mark]

thanks, tc

obviously my "search" skills are lacking i'm not much of a computer guy.
my bike still has the original coils, i'd like to try the iridiums, just wanted to make sure I don't cause any damage to the electrics.

[LoHo]

I have switched over to Iridiums on my XS and XV, as they seem to have a better spark more easily. I have found no tendency to foul, but others may have different experiences. They also seem pretty hard to wear out, but I guess we'll see.

[Rasputin]

I use the normal type spark plugs to get my bike to where I would like it to run. I do everything from high speed chops to colortune. I use the plugs and clean them before each test. When I am satisfied the bike is running the way I want it too, then I install the Iridium plugs. That way I am calibrated to my liking before I install the much more expensive plugs. I have never had any problem with these plugs after setting it up that way. I would hate to have to try to clean them and reset carbs 5 times before I was happy with the way it runs using the Iridium's. That could get expensive in a hurry.
Once I have them installed I do usually pull them after a few hundred miles to be sure every thing is ok and have never seen them bad ...yet. Expense is the only reason I set my carbs up this way as I spend a lot of time getting the mileage and power where I want it to be.

[XS1100_OEM4ME]

Any downside to these in my '80 xs1100 special? Besides the cost?
Problems with ignition systems? thanks

Wow, out of this world!

Iridium is found in meteorites with an abundance much higher than its average abundance in the Earth's crust. For this reason the unusually high abundance of iridium in the clay layer at the Cretaceous–Paleogene boundary gave rise to the Alvarez hypothesis that the impact of a massive extraterrestrial object caused the extinction of dinosaurs and many other species 65 million years ago. It is thought that the total amount of iridium in the planet Earth is much higher than that observed in crustal rocks, but as with other platinum group metals, the high density and tendency of iridium to bond with iron caused most iridium to descend below the crust when the planet was young and still molten.

The most important iridium compounds in use are the salts and acids it forms with chlorine, though iridium also forms a number of organometallic compounds used in industrial catalysis, and in research. Iridium metal is employed when high corrosion resistance at high temperatures is needed, as in high-end spark plugs, crucibles for recrystallization of semiconductors at high temperatures, and electrodes for the production of chlorine in the chloralkali process. Iridium radioisotopes are used in some radioisotope thermoelectric generators.

This kind of spark plug came into existence due to the high voltage systems of modern auto's and the 100 thousand mile tune up from new car manufactures. It has properties that allow it to resist the effects of corrosion and at high voltage spark of today’s modern motor's and last for many miles / years with today’s fuel and components.

Will it hurt your low tech bike with low voltage ignition system, no. Is it worth the $$$, not IMHO, but hey, its your $$$. It will foul faster then standard plug under weak spark systems like ours, due to the very small electrode size, but can be cleaned more often due to its extremely hard composition. A great spark plug for the high voltage self cleaning motor's of today, a waste of $$$ for a 30 year old low volt dog from yesteryear day, just IMHO

[jwhughes3]

Iridium.


Sounds legit.

Its like buying jewelry for your wife. Unlike buying jewelry for a girlfriend, where you are hoping for something in return (like good performance), your wife is already locked in. So buying her jewelry is just to show love and appreciation for the old girl (like our xs11s). And it usually gets you a day or two of "good performance"!

John

[650mark]

a great analogy. and if it doesn't hurt, then it's only money

[Bonz]

The low voltage argument doesn't make a lot of sense to me, from what I know of these plugs.

-Iridium plugs spark at a lower voltage threshold than "normal" plugs, so how does that play negatively to the old "low voltage" coils? To my mind that would allow a longer, better spark, not the reverse.

-I've run Iridium plugs in my 80SG for almost 3 years, with "old" coils and if they weren't suitable for "old" coils, I would have found out by now. I have to raise the BS flag on this theory based on thousands of miles of experience from highway to stop and go.

-My bike is tuned well, so I can't speak to plug fouling based on a bad tune or burning oil, however the same would apply to regular plugs. If you are gonna foul a plug, one that has a higher voltage thershold will have less window to opearate in than one that sparks at a lower voltage of our "old" systems. Advantage Iridium.

-From what I understand, the high mileage maintenance (plug change) intervals came about because of high energy ingintion systems when old style plugs were still in vogue. It was the high energy system that allowed the longer change interval due to stronger spark, not the plug itself. Iridium has come along and added to the durability, but it is not the reason the high energy systems came along to allow for extended plug change intervals in and of itself.

-Otherwise my 1994 Jeep Grand Cherokee would not have gone 172,000 miles on Copper Core Champions (p.o. was original owner, and I bought it with 172,000 miles on it). Yeah, the gap had opened way up, but you couldn't tell any difference with the fresh plugs in there once they were installed. That is because of the high energy system having the energy to span the gap, not the plugs themselves. I did put in Autolite Iridiums, FYI, all else equal they are a more durable plug because of the center electrode's resistance to wear. But again, no evidence that they will foul under a lower voltage system.

-I have yet to hear of Iridium plugs in any vehicle being more prone to fouling, on this forum or any of the forums I take part in. Again, experience does not bear any of this out.

Just my $.02.

[jwhughes3]

I did buy some awhile back to put into Enterprise once I get her running.



John

[XS1100_OEM4ME]

The low voltage argument doesn't make a lot of sense to me, from what I know of these plugs.

-Iridium plugs spark at a lower voltage threshold than "normal" plugs, so how does that play negatively to the old "low voltage" coils? To my mind that would allow a longer, better spark, not the reverse.

-I've run Iridium plugs in my 80SG for almost 3 years, with "old" coils and if they weren't suitable for "old" coils, I would have found out by now. I have to raise the BS flag on this theory based on thousands of miles of experience from highway to stop and go.

-My bike is tuned well, so I can't speak to plug fouling based on a bad tune or burning oil, however the same would apply to regular plugs. If you are gonna foul a plug, one that has a higher voltage thershold will have less window to opearate in than one that sparks at a lower voltage of our "old" systems. Advantage Iridium.

-From what I understand, the high mileage maintenance (plug change) intervals came about because of high energy ingintion systems when old style plugs were still in vogue. It was the high energy system that allowed the longer change interval due to stronger spark, not the plug itself. Iridium has come along and added to the durability, but it is not the reason the high energy systems came along to allow for extended plug change intervals in and of itself.

-Otherwise my 1994 Jeep Grand Cherokee would not have gone 172,000 miles on Copper Core Champions (p.o. was original owner, and I bought it with 172,000 miles on it). Yeah, the gap had opened way up, but you couldn't tell any difference with the fresh plugs in there once they were installed. That is because of the high energy system having the energy to span the gap, not the plugs themselves. I did put in Autolite Iridiums, FYI, all else equal they are a more durable plug because of the center electrode's resistance to wear. But again, no evidence that they will foul under a lower voltage system.

-I have yet to hear of Iridium plugs in any vehicle being more prone to fouling, on this forum or any of the forums I take part in. Again, experience does not bear any of this out.

Just my $.02.

Now you have

http://www.thumpertalk.com/topic/794350-iridium-spark-plugs-in-vintage-bikes/

http://www.vjmog.com/ftopic-6260-0-days0-orderasc-.html