opinion on iridium plugs

[themess]

I agree with The mess's post. A local mechanic stated that if the gap is bigger, the greater the likelyhood of complete combustion.

Sounds logical. Stock they say about .028 and he suggested .035, so I've been doing it ever since. Seems to work.

If you just look at the difference between the two gaps you can see that a much larger spark will result.

Don't know a thing about Iridiums.

In the '70s, the now-defunct magazine Cycle published a lot of good technical articles. An article on spark plugs explained reasons for larger and smaller gaps, and said that in almost all applications the best gap is 0.035". But most motorcycles of the era specified smaller gaps. This was only because the alternators of the day couldn't pump out enough power to run coils big enough to consistently reach a voltage that would throw a spark across a gap that large. That explains the 0.028" gap.

Lots of GSRers own very new bikes. What is the factory recommended gap on those?

[lecroy]

But most motorcycles of the era specified smaller gaps. This was only because the alternators of the day couldn't pump out enough power to run coils big enough to consistently reach a voltage that would throw a spark across a gap that large. That explains the 0.028" gap.

Lots of GSRers own very new bikes. What is the factory recommended gap on those?

My old Triumph I ran 0.022".

In my old H2 (have to laugh what they sell these for now) I ran plugs that were flat across the face. There was no way to adjust the gap. Older than that most of my bikes had a mag.

My old Hodaka dirt bike w/mag was 0.024"

I think my 94 GSX1100RW (all stock) is 0.026" and she is a plug eater. Not sure how much energy the stock ignition is good for. Something to measure but I would guess its well under 100mJ. It's weak. I doubt there is a plug made that this bike won't foul out once the temperatures fall below 40.

When I was running Methanol (race bike) I was in the low 20s gap. If you spray, it gets a little less.

With my current setup (gasoline) I am running NGK D9EAs set around 0.030" to 0.035" This ignition will put out 190mJ once the RPMs are up. At idle (where the bike makes a lot of sludge in the intake) it can put out 2.28 Joules. Its more like a flame thrower and can arc 2+ inches in air. I never foul a plug with this ignition.

The following is from the ignition manual...
Spark Plugs: Choosing the correct spark plug design and heat range is important when trying to get the best performance possible. Since there
are so many engine combinations and manufacturers, FDP cannot recommend which plug or gap is exactly right for your application.
It is recommended to follow the engine builder or manufacturer’s specification for spark plugs. With that, you can then experiment with the plug
gap to obtain the best performance. The gap of the plugs can be opened in 0.005" increments, then tested until the best performance is obtained.

[Dink]

No recommendations, just that NGA are crap?

Are you just looking at the plug with your eyes while your cranking over the motor and that's how you determined there is no spark?

No the cold pipes, poor performence, backfiring etc was a gead give away, being as I had crap NGK's in it then just a matter of finding which one this time.

Recommenrations, dont use NGK!! Am currently trying out Denso iridiums, will let you know.

Dink

[lecroy]

And what makes you think they are not fowled? Must be more to it.

[Dink]

And what makes you think they are not fowled? Must be more to it.

Visual inspection, a lot of years of experience etc etc and so forth.
Plus they were NGK plugs so I knew they would give problems.

Dink

[lecroy]

Visual inspection, a lot of years of experience etc etc and so forth.
Plus they were NGK plugs so I knew they would give problems.

Dink

Hard to see cat whiskers with your eyes, or were you under a microscope and still couldn't see anything? I normally check them this way.

With so many years experience etc etc, why not recommend something better, now?

I used Autolite, Champion, AC and some other green colored things as a kid. Started running NGK in the dirt bikes and fouls went way down. Never turned back. The new NGKs I get have a different plating but it does not seem to be causing any problems. IMO, from the 70's Champion was the worst. My bikes and sleds were rich running oil pigs and nothing lived for very long, so it was hard to blame the plugs. I used to take a dental pick and clean out the whiskers or take propane to them.

I remember a friend's old Yamaha had twin plugs in the head. One was a spare that you could swap the plug wire over once the first one fouled. Seems like another friend had one like this as well.

Other day the neighbor was trying to clean out his yard with a blower. He was pulling and pulling. I asked if he really wanted to get the yard work done or was just trying to put on a good show for the wife. Turns out, he really was trying to do some work. I headed over with some tools. 2-stroke. Had a Champion plug. Pulled it out, cranked it over, no spark. Pulled it over a few more times to air out all that raw gas and wiped the plug. No fire. Gave it the half inch air gap trick. Crack. Intalled the plug, with the gap, one pull and shes fires up. Let it warm up and push the boot down. Good to go. He may have been running 16:1 for all I know. He just looked at me funny and said I never saw anyone do that before.

New oils are much better and I doubt the 2-stroke bikers have the same problems we had as kids. The only bike I have now that fouls is the GSXR.

[saddlewarmer]

Saddle warmer,
The electrode is probably seperated inside the plug insulator.
This is one of the standard ways a plug can burn out. Especially on a high heat motor like air cooled motorcycles.

What brand and type was it? You see alot of disdain for NGK on this forum (Dink) Was it NGK?

it was a NGK D7EA. the po put those in. put a brand new NGK D8EA in. Will replace the others and see what happens. Not sure whats in my 1100. it runs good, easy starting, i'm going to check what is in it tonite. the plugs in the 1100 have over 2000 miles on them that i know of. we'll go from there.

[Dink]

Hard to see cat whiskers with your eyes, or were you under a microscope and still couldn't see anything? I normally check them this way.

With so many years experience etc etc, why not recommend something better, now?

I used Autolite, Champion, AC and some other green colored things as a kid. Started running NGK in the dirt bikes and fouls went way down. Never turned back. The new NGKs I get have a different plating but it does not seem to be causing any problems. IMO, from the 70's Champion was the worst. My bikes and sleds were rich running oil pigs and nothing lived for very long, so it was hard to blame the plugs. I used to take a dental pick and clean out the whiskers or take propane to them.

I remember a friend's old Yamaha had twin plugs in the head. One was a spare that you could swap the plug wire over once the first one fouled. Seems like another friend had one like this as well.

Other day the neighbor was trying to clean out his yard with a blower. He was pulling and pulling. I asked if he really wanted to get the yard work done or was just trying to put on a good show for the wife. Turns out, he really was trying to do some work. I headed over with some tools. 2-stroke. Had a Champion plug. Pulled it out, cranked it over, no spark. Pulled it over a few more times to air out all that raw gas and wiped the plug. No fire. Gave it the half inch air gap trick. Crack. Intalled the plug, with the gap, one pull and shes fires up. Let it warm up and push the boot down. Good to go. He may have been running 16:1 for all I know. He just looked at me funny and said I never saw anyone do that before.

New oils are much better and I doubt the 2-stroke bikers have the same problems we had as kids. The only bike I have now that fouls is the GSXR.

So let me see if I get this or not! You cannot accept that anyone has a different opinion than you?? I PERSONALLY and professionally have only ever had NGK plugs dud out, get over it, especially if your experience is different. Remember this thread asked for opinions.

BTW no I did not look for "whiskers" it was an NGK plug so I was witing for it to crap out, I knew they would, I may have previously stated my opinion here "NGK are crap"

Dink

[lecroy]

>So let me see if I get this or not! You cannot accept that anyone has a different opinion than you??

Accept? You mean take something said or written as truth without data to back it up? No, I am not in the habbit of doing so.

I was looking for data was all. You talk about all of your experience and I was asking you to share it. Most "professionals" are willing to help out those of us who are less gifted.

[johnnysuperbike]

I put NGK iridiums in mine, it idled a little better, no other noticable gain