Iridium spark plugs

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Realitybites
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Iridium spark plugs

Post by Realitybites »

Quick question, does anyone use Iridium plugs and if so was there a big difference in either longevity, reliability or spark?

From what I can see NGK says the DPR8EIX-9 Iridium, or the DP8EA-9, just wondering if the iridium are worth it.

Cheers!
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Stig
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Post by Stig »

I've not tried them in the bike but a few years back I ran a Renault 5 GT turbo on splitfire plugs. It made the car run alot smoother, improved efficiency, they lasted longer than the OEM recommended plugs and they were cheaper :nod:
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faststeve
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Post by faststeve »

No difference at all, waste of cash, unless your doing massive mileages, go with NGK DP8EA 9 projected nose plugs, better running and cheap, iridium don't wear out as quick but how often do you really change plugs, ?? they will not make it faster / wheelie / sound like a moto gp bike or save fuel, in fact from experience I'm not even sure they run as well as standard in the exup,
iv only had bikes for 40 years , what do i know ???????
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Post by Realitybites »

Great! thanks, so iridium coated snake oil then.
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Post by faststeve »

I wouldn't call them snake oil, they are good but only for long life / high mileage, it's got to be a bit of a myth that performance will be better with them, put new plugs in anything and it will obviously seem better regardless of what they are, mine has the DP8EA 9 and never have any worries at all, I
iv only had bikes for 40 years , what do i know ???????
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YAMAEXUP
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Post by YAMAEXUP »

My NGK catalogue suggests the DR8ES-L as a standard plug, the DR8EVX as a platinum or the DR8EIX as the Iridium plug for the 89-93 Rxups. Go installing a longer reach plug & you might go hitting the piston at high engine revs.

I tried a Splitfire plug in my XR400, as recommended by the rep at a bike show...& it caused severe running problems. Since reinstalling an original spec NGK plug i've never had a problem.

But in my KTM enduro 450 i've been using an Iridium plug for a few hundred miles now & it gives better throttle response & better mileage. But then this is a competition machine & I don't mind spending a few extra spondulies.

(Got Iridium plugs in the R1 as well :nod: )
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Post by Killawife »

I've used iridium plugs in my YZF 750 and in a volvo I'm driving now. I've noticed no difference whatsoever compared to regular plugs. They should last at least five times longer though.
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Post by Pitbull »

I've use them in my bike,

By what I understand they are heated better during the winter, so you don't need the choke when starting the bike in the mornings,
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Post by faststeve »

With regard to hitting the piston with projector plugs, they don't, I belive the us spec exup use them as standard,
iv only had bikes for 40 years , what do i know ???????
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itsnotagenesis
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Post by itsnotagenesis »

I used them in my Exup and found that it started a lot easier with them.
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