Installed New Iridum Spark Plugs

The Silverwing I bought had 5900 miles on it and seemed to be all original with a possible oil change. Installed NGK iridum plugs yesterday>>runs much smoother and revs quicker. The original plugs were just standard plugs with even burning on electrodes.
New plugs went in in 15 min..used anti seize on threads of the plugs and the boots got a shot of electro spark plug gel..
With the new K&N air filter..much better ride...

I'm glad it improved your bike. I have the plugs just waiting a little longer to install. 6250 miles no issues.
I'd run some fuel injector cleaner also, not too much. 1 OZ per gallon of gas. Techron, Seafoam. ECT.
Any good stuff will help. Cleans injectors, removes carbon from valves and cylinders.

I have been running Autolite XS4303 iridium plugs for over a year, (6500 miles, installed them when I got the scoot' with 9100 miles on it) with no issues. Don't know that they provided any "improvement" that just installing new plugs of any kind would not have provided--a clean spark is a clean spark--but I am certain I will not have to change them again for another 30+k miles or so...

OEM plugs last up to at least 50,000 miles. My waste money? Present left over SilverWing, changed Original plugs at 40,000....because I could, not because I had to, replaced with OEM. Most here do not ride enough to change plugs, ever.

Changed to the NGK Iridium at around 8K (Honda's recommendation). Now have over 21K and all is great. If you shop around, you can find the Iridium plugs for about the same price as OEM from dealer. No brainer for me. PLUS I have a friend that ordered a set for his SWing then sold the scoot so gave me his Iridium plugs for my scooter. Will probably never need them LOL.

I paid 5 bucks a piece for the NGK Irdium plugs..I have had over 40 motorcycles and all have had better throttle response and performance from changing the plugs. Probably could have indexed the plugs.. just kidding it is only a 600cc engine but checking the plugs gives indication of fuel injection and ignition health. Much better ride with the plugs..i did run 1oz of cleaner in the fuel. Todays fuels leave a lot of deposits on the plugs and combustion chambers..cheap service for better performance..

$5 each for iridium plugs? Where?

$10.11 for two Autolite XS4303 from RockAuto--with shipping:


I run the Autolite XP5325 iridium plugs in my '09 Tacoma 4.0L V6 ($4.01 each), and their XP3923 in the wife's '03 Highlander ($3.96 ea.). The plugs in the HIghlander have over 60k miles on them...

I changed my bog standard NGK's over to Iridiums last summer, simply because I'd bought them for not much more than the cost of standard plugs and they'd sat on a shelf for a year.

When I eventually sell the Silver Wing, I'll consider removing the Iridium plugs and putting the original plugs back.

As they say what ever floats your boat. The best thing that happend to spark plugs in the last 10 years was the removal of lead in what they now call gasoline. I believe the change to Iridum in spark plugs was to extend the spark life and not for performance. Some engines have spark plugs that are difficult to remove and at a considerable expense. Howard

As part of 16,000 mile maintenance and getting ready for a long road trip, yesterday I also changed  to iridium plugs on my 2002 Silverwing. I didn't notice a performance  improvement and I haven't put enough miles on her since yesterday to determine if mileage increased.
Since I stopped driving two-strokes back in the 70s I don't recall ever having an actual problem with a spark plug, but I regularly change them per the manual - in this case every 8,000 miles.  With the iridiums, I plan to wait 50,000 miles.  The plugs I took out were NGK CR8EH-9. I'm guessing they were the original plugs (since everything but the tires appeared to be original). Taking into consideration that the plugs were probably old enough to be tried as adults in Texas, the plugs were very pitted, whitish/grayish color and looked to me as if they had been running too hot. SO,  since almost all the 2,000 or so miles while I've had this scooter were and will continue to be 70 MPH highway Central Texas driving, I replaced the spark plugs with the slightly colder CR9EIX-9. I'm wondering if anybody else was using a colder plug and if so why, which one, and how did it work out?

Precious metal "fine wire" electrode plugs will not provide any performance improvement over a fresh set of conventional "fat wire" nickel-chrome electrode plugs--despite many marketing departments saying they will.

They will however provide a well formed spark longer and more consistently than conventional plugs. They also require less voltage for gap ionisation and maintaining the arc during the firing event--this makes ignition coils, especially the COPs¹ used on most contemporary vehicles run cooler and last longer.

Modern ignitions systems, especially COP based systems are also so powerful they will continue to fire badly worn plugs far beyond their useful life, leading to reports of conventional plugs "lasting" far beyond their recommended service life--albeit all the time overheating and damaging the coils. 80+% of the bad COPs I have serviced had been overheated due to worn plugs that shouid have been replaced thousands of mile ago--but the poor little COP gave it's life keeping them sparking.  


---------------------------------------------
¹ - COP (Coil On Plug) ignition coils in normal operation use only a fraction of their charge each time a normally gapped plug fires, but as the gap erodes the voltage needed to ionise the plug gap and maintain the arc rises using more of the coil's charge. The coil is working harder and runs hotter.  

With an ignition coil tester I made some years back (I really got into COP ignitions) I can burn out COPs (too hot to hold and with the smoke leaking out) with just 25 to 30 rapid firings across a 16 mm air gap, like this:

COP Firing Across 16 mm gap (MP4)

the test setup:



my bad COP collection:

I switched to iridium for the extended life more than performance. Have used them in cars for over 10 years and they last and last. I believe they use less voltage to fire but that may be in my head . Both my Silver Wing and Goldwing are running NGK iridium plugs and they work fine!!!

I buy quite a few parts from RockAuto best prices buy far. Great selection and prices. Bought my plugs there as well.

Just recommissioned a low mileage 2002 Silverwing for the road and fitted NGK iridium plugs as a replacement for the originals.Longer service life is all that I am expecting from them.