iridium SPARK PLUGS

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Yeah I saw a huge differece....in my wallet!
Performance wise I could not feel any better running or start up. Cheapo NGKs for me!
 
Mine came with them in. When I checked them, one of them's electrode had partially melted, and there was a "splash" of metal on the porcelain. I replaced them all with stock NGK's, and noticed zero difference.

The only argument I've heard in favor of the iridium plugs is that spark propagates easier from a point than a plane. This can help on newer, FI motors where they tend to lean out on acceleration. Some people report the throttle feels "crisper" after installing them, others say that's probably placebo effect since they just paid $10 a plug. Plugs can't create horsepower out of thin air, any noticed benefit is just restoring lost original performance from a poor plug.

Some of the multi-electrode plugs are popular with 2 stroke owners, since there is a general consensus that they don't foul as easily as traditional ones.


COP's did make a big difference though in responsiveness and easier startup, just using stock plugs.
 
I'm not sure I agree with easier startup. It would only help if something was amiss with stock components and/or carburation. Mine starts in a couple of turns of the starter. Doesn't matter if it's 110 or 20. Key is amount of choke. IMO.
 
some are saying irridium are more durable...
I use the irridium type but i cannot say they make a difference on the vmax
 
Yeah, durability doesn't matter to me. I replace them every spring anyway and they are only $2 each.
 
Heres my take on spark plugs & combustion ; a spark is only & I mean only the the first and least important component in the combustion / making power process , it only triggers the combustion , the amount & type of fuel - amount of air and its oxygen content - and how much its compressed , dictates how big the boom is when the spark plug " sparks " ! ..... ps. just for the record , I'm not comparing a Briggs & stratton lawn mower to a Nitro Funny Car either !
 
Let see Iridium NGK vs. stock NGK for the V-max?
Stock NGK gen-1 V-max recommendation is to change every 4K~8k miles
Iridium NGK recommendation is to change every 60K~100K miles.
Stock Gen-2 V-max from the factory has Iridium NGK’s installed. Do you think a manufacture is willingly without need going to add cost to their product to help cut into their profits on each & every unit? My experience with stock NGK’s vs. Iridium NGK has been a customer’s gen-1 that would not and/or struggled on re-start after warmed-up, then we installed Iridium’s and bike hasn’t failed on a warm re-start yet two year later. I’ve also noticed (with my own bikes) that Iridium’s seem to be less susceptible to fuel fouling, and when they do fuel foul and corrections are made they recover without having to change them. Three years ago I rebuilt an engine for my 2001 max & installed Iridium’s (@ startup) they are still the same ones in the bike today. Two year ago I rebuilt engine for my Fazer & installed Iridium’s (@ startup) I changed them once out of gilt, while beating this bike on the track for the past two summers. V-gas bike there’s a good one you’ll have to change your plugs every 400~500 miles, the V-gas system just tears the hell out of the plugs. While I also have Iridium’s in that bike and changed them once & gave the old plugs to a friend.
 
LETS PRETEND THAT I DON'T EVEN NO WHAT COMBUSTION IS , WHAT WOULD MAKE A IRIDIUM PLUG START A 1986 V-MAX ANY BETTER THEN A STOCK PLUG WHEN THERE IS NOTHING WRONG WITH THE BIKE ? ... I AM NOT DEBATING THIS , MAYBE I WILL LEARN SOMETHING , I JUST DON'T UNDERSTAND HOW IT CAN JUST HAVE TO DO WITH THE SPARK PLUG ALONE :confused2:
 
Spark jumps from a very small point much easier than from a large surface, like lightening hitting a antenna top in preference to a flat steel roof on a shed.
Iridium's have a very small centre conductor, which means a much easier spark, and because it travels to the same size outer electrode, the flame kernel is less shrouded and normally more intense, making it less susceptible to crboning up or fueling up.
You could make the same style of plug using copper, but wouldn't last. The Iridium centre material metal can withstand much higher temps without breaking down the surface, so lasts much longer as well.

There you go! :biglaugh:

And yes, got them in my bike, but in Denso not NGK (the tops unscrew, so keep the same leads as standard).
 
Only thing I have heard from some who have them is they last longer than a standard plug and can be gapped wider than a standard plug. Also some claim easier starting but I have yet to hear anyone say they actually have any "seat of the pants" performance increases. I'll stick with stock.
My .02
Later
Duke
 
Not that my bike was difficult to start before, but is is definitely easier now. Think firing on the first compression, every time. Barely poke the starter and it's running.

Some people change plugs constantly, and I just don't get why. I mean I guess if it makes you sleep better at night, but even cheap copper plugs last a very, very long time. My truck takes regular copper plugs, and the replacement spec is 100k miles. But Ford 5.4's like to seize plugs into the head, so I don't think that's going to happen. A lot of people have over 300k on the original plugs with no misfires or anything like that (because the engine head wouldn't surrender the plugs even if you wanted to)

For most people, 100k miles in a car relates to about 2500 hours of driving. So why does a cheap plug in a car last for 2500 hours (at least), where the same material and design in a motorcycle only lasts 5k?

Probably the same reason car tires last for 60k miles, and bike tires cost twice as much and last only 5k miles.
 
not that my bike was difficult to start before, but is is definitely easier now. Think firing on the first compression, every time. Barely poke the starter and it's running.

Some people change plugs constantly, and i just don't get why. I mean i guess if it makes you sleep better at night, but even cheap copper plugs last a very, very long time. My truck takes regular copper plugs, and the replacement spec is 100k miles. But ford 5.4's like to seize plugs into the head, so i don't think that's going to happen. A lot of people have over 300k on the original plugs with no misfires or anything like that (because the engine head wouldn't surrender the plugs even if you wanted to)

for most people, 100k miles in a car relates to about 2500 hours of driving. So why does a cheap plug in a car last for 2500 hours (at least), where the same material and design in a motorcycle only lasts 5k?

Probably the same reason car tires last for 60k miles, and bike tires cost twice as much and last only 5k miles.
Thank you "RA" for posting all of what you wrote ! ... The plugs that get stuck in the heads i deal with all of the time ! ... Just yesterday i put spark plugs in a ford escape with a 118,000 miles on the original plugs , air filter was plugged solid ! A lot of automobile manufactures use that as a sales point " your first scheduled tune up is 100.000 miles " that doesn't mean the plugs are going to come out of the head ! ... Call ford and ask how many broken plugs they warranty ? ... " none " ! ... And their fix is to replace the heads ! ... As far as Yamaha loosing profits by installing iridium plugs , they don't pay over the counter prices , they get them for next to nothing & the more they get the cheaper they are ! ... Its like free advertising for the plug manufacturer ! ... And if manufacturers did everything correctly , there would be no such thing as technical service bulletins - recalls - and no need for aftermarket parts because the " best " parts money could buy would already be on the bike ! ! ! ..... Just on a side note , the starter of the thread who has a 1986 v-max , asks if he would feel the difference , he didn't mention that he had a starting problem or cared whether or not they lasted 100,000 miles , it sounded to me like he wanted to no if he would have a performance gain ! ... So i guess i can safely say " absolutely not '' ! ... The best thing about a spark plug debate is when i had my last stock car i tried every spark plug on the market and every plug gap-able from .0035 - .0075 , i would rent the track every Saturday and run about 200 laps and no matter what type of plug or its gap never made not one rpm. Difference on my " monster tell-tale tach " ! .. Not one ! ... Plus i even tried plugs with much longer threads , so if anything , they would reach deeper into the cylinders to try to bring up the compression , nothing made a difference ! ... when i was helping a couple of feather lite modified teams , with $40,000.00 + engines , they all used just regular spark plugs ! .... to each there own , but if my max ever gets hard to start , i am going to get iridium plugs , just to see for myself ! ... :punk: ps. I'm not saying i don't believe what anybody on this thread is saying , some things i just would need to see for myself ! ... :confused2:
 
so i pretty sure now that i will stick to the cheap ngk plugs. here in greece the y sell the iridium plugs about 40 euros each(thiefs) and as i was searching in ebay i saw them very cheap. but after reading the testimoninals there is no need of iridium on my max.
 
"Use the Admantiums myself....hell of a plug! Did you get the ones with the built in compression test port?"

Of course. How else can you hook up the oil injection so my Max can sound, smoke, and perform like a Harley?:biglaugh:
 
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