okay iridium plugs

[mikey]

any one know how iridium plugs for my 91..600. will work? my brother put ngk 9dpr8ea plugs in his 87 hurricaine. should i use them owill my iridium (ngk dr8eix) work okay. this is what advanced gave me but som e spark plug cross refrence site said my ngk plugs r for cars. just woundering if u guys/ gals have ne imput?

[steves]

I'm having a hard time understanding your question due to the poor spelling and lack of grammar, however I think the question was "What do you think of iridium plugs, and what size fits my bike"

http://katriders.com/wiki/index.php5?title=Spark_Plug

DR8EIX is the correct plug.

As to if I think you should use them, no I do not think they are worth it.

[05RedKat600]

If the factory didn't require them, all you're doing is throwing away money. Stick with regular NGK plugs, they work just fine.

[DClark]

If the factory didn't require them, all you're doing is throwing away money. Stick with regular NGK plugs, they work just fine.

Not true, as I have posted in the past. I saw a set of Ir plugs with 16k miles post higher hp #'s on the dyno than a set of brand new copper plugs. The ir makes for a narrow electrode which means bigger spark.
They outperform regular plugs in every area, that's why they are becoming standard issue on high performance stuff like zx 14 (and my C14).
I have a set in my kat 1100 with double the recommended gap, dyna coils hooked to relays and it runs great with much better cold starting.

[05RedKat600]

What kind of higher HP numbers? My point was, 3 dollar plugs vs 10 dollar each plugs. Sure, they last longer, but the cost of IR's and regulars is, in the end, the same. 3 sets of regulars vs one set of IR's.

I would be very interested in seeing Dyno numbers for the tests you speak of. Hi-Po 4 cylinder cars dyno 1.5 HP more with IR plugs, can't see a Kat doing much more than a 1 HP increase.

Also, the better cold starting can't be attributed to just the plugs in your Kat. You have the relay mod, plus aftermarket coils and a larger gap. I've been running regular NGK plugs for years in lots of stuff I own, and never had an issue.

[GSXFJim]

I pulled a set of stock NKG's with an unknown number of miles on them from my 750, thinking that would need replacing for sure... they were in great shape.. I cleaned them, checked the gap and put them back in. I now have a spare new set of plugs on the shelf...
As for HP numbers.. the cost vs. possibly adding 1 or 2HP, that's up to the rider.. is it worth it?.. and are the HP numbers accurate across the board for every bike?.. unless your dicing with the likes of Stoner and Rossi and you need that 1hp advantage..... I'd put the stock units back in and call it a day... jmo

[arsenic]

Here we go with the "spark plugs make better HP" thing. Why not use Split Fire plugs. Then you can beat a GSXR.

[05RedKat600]

Here we go with the "spark plugs make better HP" thing. Why not use Split Fire plugs. Then you can beat a GSXR.

But if you put in the Bosch Platinum 4's, that's 4 times the spark area and you can beat a 'Busa.........

[arsenic]

Well, since a GSXR would own a POS 'Busa, I'm not too worried about beating that abortion. (I HATE that bike BTW)

[DClark]

What kind of higher HP numbers? My point was, 3 dollar plugs vs 10 dollar each plugs. Sure, they last longer, but the cost of IR's and regulars is, in the end, the same. 3 sets of regulars vs one set of IR's.

I would be very interested in seeing Dyno numbers for the tests you speak of. Hi-Po 4 cylinder cars dyno 1.5 HP more with IR plugs, can't see a Kat doing much more than a 1 HP increase.

Also, the better cold starting can't be attributed to just the plugs in your Kat. You have the relay mod, plus aftermarket coils and a larger gap. I've been running regular NGK plugs for years in lots of stuff I own, and never had an issue.

Saw the increase on my GTO at Advance Dyno in the bay area. The point is not the small increase (2hp) which, no ****, is small. The point is that a set of old (16kmiles) plugs outperformed brand new,right out of the box copper plugs.
My bike ran better with IR plugs before the coil mod. Assuming you live in Portland, Or, you don't get cold there nor do you ride in the cold. Where I live, we can get below zero in the winter and very often, I'll ride when it is is single digits. My bike used to be a bear to start up in those temps. Even when it is in the 50's, I can start the bike up with no choke. The idle is real smooth and it feels a bit more powerful after 5k rpms. Cyberpoet did a write up on these somewhere as well. You can look it up yourself, IR plugs work better, more powerful spark, less spark shroud, more resistant to fouling, longer life. Standard equipment now on most sports cars and high performance bikes.

http://www.densoiridium.com/faq.php

These bikes have weak ignitions and things like IR plugs and relays are improvement. i say weak ignitions because for a low cr motor, they sure have a small plug gap.

[arsenic]

I remember exactly what The CyberPoet said about IR plugs. And it was not that IR plugs are any better. They simply heat up faster. So he said, if your average ride is 10 minutes, use IR. If you take longer rides, don't waste your money.

[05RedKat600]

Saw the increase on my GTO at Advance Dyno in the bay area. The point is not the small increase (2hp) which, no ****, is small. The point is that a set of old (16kmiles) plugs outperformed brand new,right out of the box copper plugs.
My bike ran better with IR plugs before the coil mod. Assuming you live in Portland, Or, you don't get cold there nor do you ride in the cold. Where I live, we can get below zero in the winter and very often, I'll ride when it is is single digits. My bike used to be a bear to start up in those temps. Even when it is in the 50's, I can start the bike up with no choke. The idle is real smooth and it feels a bit more powerful after 5k rpms. Cyberpoet did a write up on these somewhere as well. You can look it up yourself, IR plugs work better, more powerful spark, less spark shroud, more resistant to fouling, longer life. Standard equipment now on most sports cars and high performance bikes.

http://www.densoiridium.com/faq.php

These bikes have weak ignitions and things like IR plugs and relays are improvement. i say weak ignitions because for a low cr motor, they sure have a small plug gap.

16K miles on IR plugs is old? Hell, for 10 bucks a pop I don't want any then. These are supposed to go 100-120K miles, so 16K is not old, it's not even broke in yet. I can get a 2 HP increase on the dyno by changing my air filter too, and that costs a lot less.

You are forgetting a key word: For you they work better, not for everyone.

Standard equipment on sports cars and Hi-Po bikes, you said it yourself, the Kat is anything but, and the motor isn't Hi-Po either. Again, no need for IR when copper works just as well. It's not a CBR, Busa, or other hi performance motor. It's like running iridiums in a Model A.

[steves]

FWIW plugs in cars, are not like plugs in bikes. The car systems are much more sophisticated especially on FI systems.

But, you know, do what you gotta do. I sell the plugs and don't recommend people go IR.

[TRPUT]

I recently put Iridium plugs in the post - mainly because I could have them delivered to my door from the US for less than a set of standard plugs here in Oz. ($40/set delivered vs $42 for a set of standard NGK - prices suck here!) Fitted the coil mod at the same time. Not that I ring the bike's neck, but I can't really say there is any great improvement across the board. It might cold-start better??? The other benefit I'm hoping for is reduced maintenance in not having to remove / clean / replace the buggers for a while. But would I pay 3 times as much as standard plugs for them??? Don't think so.