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Premium Member
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Discussion Starter #1
I don't recall if I mentioned here that I was having some cold starting issues, but when it's been in the 20's or 30's, especially if it's been wet out and I haven't ridden for several days, the bike was getting harder and harder to start. I'd crank and crank and sometimes felt like I was going to run the battery down (MF) before it would fire up. Then it ran fine and started fine around noon when I'd go out to leave for lunch. I finally bought the iridium plugs and installed them. I immediately took it for a ride and maybe (subconciously) it felt like it had a little more power and ran smoother. That night the cold hit and we had ice and sleet and rain/freezing rain for several days, so I didn't get to ride for nearly a week. First dry (but cold 28 degree) morning, I decided to ride again. Went out and pulled on the choke and it fired on the first touch, but died. I hit it again and it fired right up and warmed up nicely. It's fired on the first touch every since. The new plugs made that issue go away. It could be that any new plugs would have made that difference, but the old plugs looked fine, not carboned up or anything that would suggest why I was having that problem.

If you're having starting issues, and have an MF battery, and the bike runs fine otherwise, I'd suggest the iridium plugs. NGK part 7803. I'm sold on them!
 

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what gap are you running, what did u use to measure it?
 

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Discussion Starter #4
Previous plugs were NGK. I'm pretty sure they were original plugs. Had 17,000 miles on them. I checked the gap with feeler gauge, but they were all four already at .035 so I left them there.
 

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Thats quite a few miles on those plugs.New plugs whatever ones that you use will make a considerable difference. But Im glad you got it straightend out.....................
 

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Benjammin'
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421 Posts
Iridium plugs....I got 'em too

I have to say that my bike starting has changed drastically since I put the Iridiums in it. The bike had about 6k and I am sure the plugs were changed out previously to me getting the bike (the old ones were in with the tool kit in the tool box). Anyway, cold starts are great, but what I like even better is the warm start backfire is gone. It was to the point where I refused to shut the bike off if I was going to start it right back up because of the embarrasing KA-POW!!!

I agree about the power. The bike does feel more responsive with the plugs, though probably my imagination. The plugs are pricey, but supposedly the last plugs you will need to buy. OH- DON'T FORGET NEVER-SEIZE ON THE THREADS!

I bought the NGK plugs with the U-groove. I figured if I was going for it to go all out.
 

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Drive less, ride more...
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1,114 Posts
If the "fire in the hole" is that much better with these new plugs, I have to wonder how much they improve fuel efficiency.

Heck, everybody knows that as warm weather comes back, gasoline will (again!...:mad:) get expensive....so does anybody know of any proven test data on how these plugs help save gas?
 

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and the Adventure Cycle
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6,141 Posts
what do four of the iridiums run price-wise?
Summit Racing has them for $6.99 ea.
I couldn't find a price on the Advanced Auto site.

Also as far as what kind of MPG improvment they make, this was copied from the Vulcan Verses...

I had the same experience with these last year, Dennis. Now I just have to barely breathe on the start button and she starts right up. I figured they're well worth the slight extra cost. A lot of us spend way more than that on cosmetic upgrades and shiny chrome bits. I bought mine at Shade Tree for abt $8 ea. They should last longer, and I since I also keep detailed track of my gas mileage all the time, I also noticed an average increase of about 2 MPG after installing them See if you notice the same thing.... -Tim S.
 

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it would be interesting to see a dyno comparison between plugs. i doubt there would be any big gains, but i bet the curve would look a lil different
 

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Discussion Starter #13
I paid 8-something each for them. Once I made up my mind I wanted them, I wanted them yesterday so I called my local NAPA and got them the next day.

I actually might be experiencing a little higher mileage out of them as I just looked at my last couple fill up's and was getting a little over 46. So that's maybe a couple over my usual.
 

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Benjammin'
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421 Posts
Iridiums....

I did some research on plugs and was amazed at the technology that went into getting a tiny spark to ignite fumes in an enclosed chamber. Bottom line is, a plug will not make a cylinder fire any better than it was designed to, but make more efficient use of what was designed. There are terms such as "quenching" and "kernel" that are used to define this efficiency. As I learned, iridium requires less voltage to spark, and uses cone, tip and electrode design to maximize spreading the arc potential to completely ignite the chamer all at once, not starting in the middle and through expansion, working its way to the edges of the cylinder, sometimes after piston movement has begun.

Another thing I think is really beneficial to our bikes with these plugs is less strain on our electrical system to comparably fire the plugs. As we all know, the electrical system is the achilles heel of our bikes, and the less electrical requirement needed to make it run, I would expect it to be better long term.

OK- having bored you to tears with the technogarbage, I found two brands that I liked that offered plugs for our bikes;
NGK = DPR7EIX-9 with V-groove technology (I misspoke earlier)
http://www.ngksparkplugs.com/products/motorcycles/iridiumix.asp?nav=12000&country=US
and Denso = IX22B with U-Grove power
http://www.densoiridium.com/patentedtechnology.php
The web address should helo explain what each plug can do.

Here is more technobabble about why U (or V) Groove works;
"V-cut ground electrodes are called a variety of names depending on manufacturer. Although they look similar, they may be called a tapered cut ground, trimmed side electrode, wedge shaped ground, v-trimmed electrode, inverted v-tip ground, v-power (NGK) or U-groove (Denso). So what's the point? The v-cut give the flame a groove to grow in and forces the spark to the outer edge of the ground electrode - placing it close to the air/fuel mixture and creating a larger flame that ignites quicker for a more complete combustion, even in the case of lean air/fuel mixture. A conventional, flat ground electrode design of regular plugs crushes the flame (sometimes called quenching), thereby preventing full spark potential."

Sorry for making such a long post, but I am truely sold on the benefits of these plugs because of first hand experience.

Good luck....
 
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and the Adventure Cycle
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No need to be sorry Ben, That was an interesting read! Thanks for the info :smiley_th
 

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I am sold on spark technology as well. I will not produce major gains, but as you stated have it run more efficent. Since you found that they require less voltage to spark, this means that in theory we can increase the spark gap.

There are 2 key things in a spark. heat and surface area. A hotter spark will ignite a higher initial percentage of the air/fuel mix. Surface area will increase the inital fuel as well. The key is to get the highest surface area with the hottest benificial spark. So if by keeping the stock gap, you gain an extra 5% initial combustion, vs if you increase the gap by 15% and maintian the stock initial combustion, the cyl will ignite faster with the larger gap cause more fuel was initially burned.... Well atleast that is how i understand it in theory.

aftermarket coils and irridum plugs, same temp spark, larger gap= better burn
 

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I tried to find these plugs @ 2 of our local auto stores, No luck. So I went to our Kaw dealer to find out if they had them in stock.
By the way, I told him for what reason ie..starting problems and how it seems to help with a MF battery, Sea Foam Apps, and now these plugs. He stated "sounds like Bulls**t to me...you all have carb problems. But I'll order them for you"
I politely left (without ordering) reminded once again why I shouldn't waste my time going in there. :mad:
So I'll just order them on-line.
Sorry had to vent.
Thanks again for all of the info
 

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House,
That is weird you get the same poor service like I get at my local Kaw shop. I always left the shop feeling like a second class citizen. Since they sell Harleys too I always figured they prefer that business over mine and stopped going. I'm very grateful for having the internet for shopping and being able to utilize this site for valuable info to keep my bike running at it's best...
 

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HAWK
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I was told by my local shop when I asked how to get more power out of this bike(before I found this sight).
"That is a beginer's bike, Why would you want to do anything to that. People get it to learn and sell it to get a real bike."
Needless to say I have never been back there.
 
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