Iridium Spark Plugs and Cold Start - User Beware

[supperduc]

Adjust the gaps to 0.035. I did and they worked for me. New out of the box gaps are set at 0.024 (at least mine were). Be very very careful with the iridium electrodes when adjusting these plugs. Good luck!

[Howie]

I've had cold start problems with my s4 sometimes it starts fine with the choke other time you have to churn it over and sometime turn of the choke in case it floods could this be plug and or gaps they are the iridium ngk once started and warm the bike pulls clean any help info would be appreciated.

P.S the plugs were only just fitted at the last service and were new out of the box but I don't know how old they are as I got them with the bike.

Your fuel injected S4 has a fast idle lever, not a choke.  When was it serviced last?

[cokey]

Reason they say not to gap the ir is cause they can break easier..  just be gentle..   anyone try the diamond ones? I tested them in my neon and al though I was running a bit hot, I thought they would last longer. The damns electrode broke off on 2 of them..   gap at .035 for winter and prob around .028-25 for racing in my case..  copper seem to work best..  I do change plugs every 2nd oil change.

[Nero-92]

Your fuel injected S4 has a fast idle lever, not a choke.  When was it serviced last?

I realise it's a fast idle but the bike from cold won't idle with out it for the first few minutes and by service do you mean oil plugs and filters or the full Monty valve clearances belts etc?

P.S the oil plugs and filters were done at Xmas.

[Nero-92]

I realise it's a fast idle but the bike from cold won't idle with out it for the first few minutes and by service do you mean oil plugs and filters or the full Monty valve clearances belts etc?

P.S the oil plugs and filters were done at Xmas.

Ok I think I've found the cause of the cold start problem ME I was foolishly using the fast idle as a choke to start the duc after being idle for a while the weather for the past 2 weeks here has been gale force winds and rain so the duc was just sitting in the garage but went to it today and started it by mistake without touching the fast idle control and it started no probs and then ajusted the fast idle lever for the first min or so happy days.

[Old-Duckman]

Good post (thanx to the "search feature" for finding it).

Had the S2R 1000 out last evening, been about 1000-ish miles since serviced. Got about 6 miles from home and noiticed a decrease in power and rough running. Was afraid it would stall when stopped so kept it reved and drifted through most stops. Got it home and it did stay lit at idle (revved, blew stop signs and worried for nothing).

So started checking...Battery volts read 13+...Battery OK. Low fuel light was working (but not on) only 104 miles on the tank...Has fuel, OK. Pull all of the plugs...all LOOKED OK.

Figured it might be a fouled plug so ordered 4 NGK Iridiums on Amazon...Today read this post...Just ordered 4 Champion copper (Champion RA 6 HC) this morning.

When sitting in the garage and running it up to 2000 to 3000 range the rough running was noticable (hot last night and cold this AM). Pulled and replaced all plugs with an old set I had kept after a service...Rough idle and miss gone !!! Glad it was just a bad plug. It had the standard NGKs installed. Will keep the old plugs in until the new ones arrive from Amazon. Not sure which I will install..Probably the Champions?

Thanx all for this very informative post/thread...wish I would have read it last night, would not have ordered the iridiums...Oh well.

[motoxmann]

copy and pasting this post I made on a different forum:

I've never used iridiums in a ducati before, but I have used them in turbo honda motors that I've built. when used in 300-500hp 4-cycl honda motors, standard copper NGK plugs would only last about 3k miles if that, whereas the iridiums lasted 8k-12k miles. BUT, the standard copper plugs actually made about 10% more power than the iridium plugs, which I first noticed from the driver's seat, and then I proved time and time again on an actual dyno.

not sure if this same effect would occur in a ducati, but just sharing my experience, and it stayed consistent like this in over 20 cars/engines. my two cents

and a more important post I made on the same forum in a different thread:

I've been a nut for NGK sparkplugs for years and years no matter what the application was. but after finding champions in my duc, I did some research n what it would cross to for an ngk plug, and found a LOT of forum posters on various websites saying NGK plugs are crap in ducatis and should NOT be used. most of the time it would run fine for a few minutes, then run choppy as heck, then run rich as heck, then rough up and foul out and die and not restart again. cleaning the plugs would make it start up again but only for a few seconds before it'd repeat itsself. but I insisted on giving it a shot cuz I love NGK plugs. I used the exact same nkg plugs you have (standard copper tip, referring to the other forum this derived from), and guess what? my bike ran fine for about 1 minute, then got choppy, then died and wouldnt restart. pulled the plugs and they were blacker than black and all wet and fouled out. cleaned em, tried again, same thing. put the champions back in (RA6HC, what my bike calls for), bike fired right up and ran amazingly for 100 miles.
while hot I tried another set of the same ngk plugs, these ones again brand new, same exact thing happened, ran fine, chopped up, fouled out, died, wouldnt restart.

get yourself the champion plugs that your bike calls for, should be right on the sticker on the frame. you may find that is the only problem with your bike

[BastrdHK]

I have had the opposite experience.  Champions under performed, while I have used NGKs for the last 18k miles with stellar performance.  No plug issues.

I have never used iridium or platinum because I could not stomach the price when getting such good performance out of the standard NGKs.  Good to hear some input on them guys.   

[motoxmann]

I have had the opposite experience.  Champions under performed, while I have used NGKs for the last 18k miles with stellar performance.  No plug issues.

I have never used iridium or platinum because I could not stomach the price when getting such good performance out of the standard NGKs.  Good to hear some input on them guys.   

what are the stock champion plugs your bikes calls for, and what NGK plugs are you using? I would love to give them a try, because I've always had better experiences with NGK plugs over champions in everything up until my ducati

[BastrdHK]

NGK DCPR8E, Champion RA8GHC

For a 2001 M900

[metroplex]

I'm running Denso Iridium's in my 2009 696, so far so good and no problems related to spark. I figure the Ducati engine is a gasoline internal combustion engine, same as my other V8s and Inline 4 car engines that also run Iridium plugs.

[ducpainter]

The manual for my 96 900 calls for RA6HC

I run DCPR8e.  They're fine.

[koko64]

The manual for my 96 900 calls for RA6HC

I run DCPR8e.  They're fine.

Most people I know with 900s do the same, that is, run the NGK equivalent to the factory spec RA6HC.
The NGK option down here seems to be the DPR8EA-9 (part no 4929) or the iridium DPR8EIX-9 (part no 4274).
I wonder what the difference is between DCPR8e and DPR8EA-9? The former seems harder to find down here.

[koko64]

Oh yeah, the .9mm (.036)  factory gap on the iridium version should be enough with strong aftermarket coils and leads? Both kinds of those NGK plugs have a bigger gap than the Haynes manual recommendation for the Champion plug.

As has been mentioned LT Snyder also recommends a larger gap for the Iridium plug. The standard type NGK plug commonly availabledown here has the bigger gap also. We are talking .9 (.036) Vs .6. (.024). I would generally tend to agree with Snyder that "the condition of the plugs and the gap are bigger determinants of spark plug performance than brand" (Desmodue Maintenance and Modification Guide).

I do note with my old 900, the iridiums gapped at .9mm or .036 are leaner looking when I tested them at idle to 1/4 throttle speeds when compared to the non iridium NGKs with the same gap.

It may well all be in the gap.

[ducpainter]

Most people I know with 900s do the same, that is, run the NGK equivalent to the factory spec RA6HC.
The NGK option down here seems to be the DPR8EA-9 (part no 4929) or the iridium DPR8EIX-9 (part no 4274).
I wonder what the difference is between DCPR8e and DPR8EA-9? The former seems harder to find down here.

I'm not exactly sure of which one I'm using.

The 8's work.

I've never fouled a plug or had any running issues.