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I run the good ol' NGKs in mine.. I forget which model number but I've got them at home if you need a number.
 

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I run the NGK CR9EIX. The book actually lists a CR9EX (I think I got that right) but the CR9EIX is the exact same plug that's listed in the book as a replacement except it's iridium. I actually ended up getting them from my local Yamaha dealership for $10.95 a piece because they were the only ones in town that had them. I went to one Ducati dealership and 6 motorcycle shops looking for the original Champion SD replacement plug and no one had them. Also, no one had the standard CR9 plug that the book called for either so I had no choice but to get the iridiums, which is no big deal.

Funny thing is I'm almost positive that write up on the Section8 web site there is incorrect. I did some research while shopping for plugs and the spark doesn't ground to the piston...it grounds to the side of the plug itself. That's a helluva gap for a spark to jump!!! But, someone please correct me if I'm misspoken. I had also heard they can foul easier than standard electrode plugs. Yes, the NGK's are a standard electrode plug. FWIW, I would have went with the Champions if I could have found them but in the end could tell absolutely no difference. Hope that helps.
 

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Bobaganoosh
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Im running Denso Iridium IX27's in my 748. If I remember correct the shop manual called for IX24... the 27 is just a little hotter spark. I am happy with the plugs and overall I think it smoothed the idle out more than the Champions. With the Denso's you will have to make a spark plug socket.

I took a cheap spark plug socket and pulled the rubber boot out and put that boot into a standard 18mm deep socket. That allowed clearance into the sparkplug hole.
 

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I must be nuts.....

Different engines, different plugs, but I just installed some Champion 8809 plugs in the 748 I found at Wal-Mart for about $3 each.

I know it's nuts, but we're always looking for cheap alternatives for fuel and oil filters, oil pressure sending switches, etc...why not plugs?
 

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loony888 said:
i run champion A55V surface discharge plugs. no probs.
Do you mean the Champion QA55V surface discharge plug? I ran across them just recently. I bought a pair directly from champion (for about $10 cheaper than some others were selling them) but haven't had the chance to install them. What do you think?
 

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scottrwilliams said:
What kind of spark plugs are you guys running? Comment, thoughts, suggestions? Are the surface discharge units worth it whats the point?

http://www.section8superbike.com/cgi-bin/section8/flypage.html?mv_arg=90
Section8 site not working.. but I think you are referring to the electrode-less plugs used in the 999R, correct? The plugs discharge directly to the piston crown...IIRC the reason those were fitted to the R's was for piston clearence. I've heard they have a tendency to foul, which doesnt suprise me if running pump gas vs. race fuel.

I wouldnt recomend using them outside their application. You figure that the "gap" is related to your piston clearence, which is much greater in non-"R" bikes.. I think you'll definitely run into fouling issues if you don't burn out the coils first.
 

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They DO NOT ground to the piston...can you imagine what kind of gap that is???? Remember, regardless of how tight it is, I guarantee it's greater than...what's a typical spark plug gap... like .7mm?? And you know the gap from the spark plug electrode (oh, BTW, SD plugs don't have your typical ground but they do have an electrode) to the top of the piston is going to be greater than that. Those engines would not be built that tight. Then you've got to factor in this...When does that spark fire?? When the piston is TDC which would be the closest point between the piston and plug??? Nope!! If I recall, I think I read that our motors fire somewhere around 5-10 deg BTDC, increasing that gap even further. Not a lot, but still. The spark grounds to the outer edges of the plug itself.

As for fouling, these plugs come stock at a minimum in the 749S...that much I can guarantee. And can also guarantee they don't foul no easier than any other plug. One other way I can guarantee the SD plugs don't ground to the top of the piston is when I had mine out, I measured from the bottom of the spark plug threads to the top of the piston at TDC...it was huge. Didn't write it down but I remember it being more than sufficient because I checked to make sure it wouldn't touch the electrode on my now conventional plugs...no where close. No way the spark could jump that gap. I pulled mine out but forgot the mileage. The only reason I pulled them was to install fresh plugs for a dyno run and couldn't find brand new Champion SD replacements anywhere in town. After installing the traditional style NGK's, it made zero difference in the bikes performance.

MAN...a year old!!! how'd you find this thread anyways???:)
 

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If the spark was discharging to the top of the piston (and it is not), what would the piston look like after oh say 5 laps around Laguna or the block where you live? Most likely it would have a hole in it.
The spark is going to the closest ground and that isn't going to be the piston, trust me.
 

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Hey, normally I dont really care to justify myself here, but I'll do it now just to blow off steam. As far as my post is concerned, if I'm off base, I'll stand corrected. For the record, I'm in friggin Baghdad working 24/7 for the next 9 months or so (Infantry). I haven't had a chance to even see my bike in over 4months now. Sometimes I'll come in from a 12 hour mission at like 3-4am go on just to get back in touch with reality, because this is the stuff I love. Sometimes my mind is not all that rational. I apologize for that, and if I give a bone-head answer, there's no need to berated a dude over that. C'mon, man.. seriously. And if you don't give a shit cause you don't like the war or Bush, I give a shit less, 'cause I, too, would much rather be home with my wife and son and riding my bike instead of dodging roadside-bombs and sniper rounds on a daily basis. *rant over*
 

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Hey Matt, guess my answer was a little agressive...not directed to you bro...Sent you a PM. Glad you at least get a MS break every once in a while. But, I do feel your pain.
 

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Hey man...you've got to vent over there every once in a while. Friggin awesome you can get an internet fix every now and then!!!
 

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i've been using SD type plugs since i got my 888, that's over 7 years now and can say with conviction that they don't foul any easier than std type plugs. i'd say they are harder to foul as i've run the dreaded shell optimax and haven't had a problem. they are the QA55V, i just left the "Q" off, sorry, and the reason i went with them was a friend had a 916 and suffered major damage when an electrode came away and got caught between the piston and liner causing untold grief between himself and his dealer, warranty issue??? etc.etc.
cheers,
paul.
 

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We used to use SD type plugs in two stroke Kawasakis back in the early seventies, especially on the three cylinder models. Eventually the factory recommended against them. Too hard on the early capacitor-discharge ignitions.
 
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