Spark Plugs, regular or iridium
- Thread starter Justyntym
- Start date
Iridium spark plugs by NGK and Densohere's a link 'bout advantages:
Stockers IMHO don't see any advantage to running the iridium. They cost more.
aussiekeeper
Registered
The Busa are running so lean that standard plugs are fine. Why irritate the ulcer with a hotter iridium plug.
They are not any "hotter" than standard plugs, their heat range is standardized and similar to any standard plug. The coils do not need to work as hard (resistance) to produce the firing spark, therefore wear on electrical components is relieved somewhat. Since the electrode is harder and has less resistance, the tip will last longer. I had a set in a large (1900 cc) v-twin for 28,000 miles, at that mileage, they still looked new.............On some automobiles equipped with Iridium from the factory, the change out is at 50,000 miles or more for regular service. Does anyone like to replace spark plugs? Not if we don't have to.
aussiekeeper
Registered
Probably don't need to.......I just check one once in a while.
standard plugs in a stock busa will run 20K miles even beating on the bike..
IMHO, the extra money for the "trick" plugs is probably just a waste of $$.. Sparkplugs will only hand you HP if there was something wrong with the old ones.. Old ones are always fixed by "new" ones... The bike can not tell what the brand or type of plug you have installed.. It can only tell if there is a good spark available.. As the stockers worked just fine, there is not much reason to think the iridium is going to work better..
There are a few exceptions.. a bike that is "mis-tuned" can keep an iridium plug from fouling longer (small tips resist carbon fouling)
If you are running a hot rod motor, then there can be some advantages to an iridium plug but again it just relates to fouling..
Swapping to "cheap" knock-off brands is a different story.. they can be a can of worms.. There is so much "mis-understood" about sparkplugs and "heat ranges" IE a hotter plug does not have a hotter spark, it runs at a higher temp by moving the electrode further away from the body of the plug where heat is bled off.. Can cure carbon/fuel fouling or can burn a motor to the ground when it turns into a "glow plug"
keep the stock plug in the thing IMO..
IMHO, the extra money for the "trick" plugs is probably just a waste of $$.. Sparkplugs will only hand you HP if there was something wrong with the old ones.. Old ones are always fixed by "new" ones... The bike can not tell what the brand or type of plug you have installed.. It can only tell if there is a good spark available.. As the stockers worked just fine, there is not much reason to think the iridium is going to work better..
There are a few exceptions.. a bike that is "mis-tuned" can keep an iridium plug from fouling longer (small tips resist carbon fouling)
If you are running a hot rod motor, then there can be some advantages to an iridium plug but again it just relates to fouling..
Swapping to "cheap" knock-off brands is a different story.. they can be a can of worms.. There is so much "mis-understood" about sparkplugs and "heat ranges" IE a hotter plug does not have a hotter spark, it runs at a higher temp by moving the electrode further away from the body of the plug where heat is bled off.. Can cure carbon/fuel fouling or can burn a motor to the ground when it turns into a "glow plug"
keep the stock plug in the thing IMO..
I've thought about using Irridium plugs, but the shop that I buy my stuff from (the place that SELLS them) says, "waste of money". So I stay with the standard NGKs.
if the plugs are ready for change, typically 2 things will happen
fuel mileage will drop and hard starts will start happening.. other than that, there is no reason to change out a sparkplug.. they can not hurt an engine if they are run beyond the "suggested service life" unless you run them dead.. (fuel contamination to crankcase)
Service life is based on a few things (including profit margins).. I personally figure if you are not working on stuff, you are not breaking or dropping stuff into the motor, tugging on wires or running a chance of disturbing stuff that was just fine to start with..
Some are fine with the extra work, I just prefer not to work on stuff that is not broke just yet
fuel mileage will drop and hard starts will start happening.. other than that, there is no reason to change out a sparkplug.. they can not hurt an engine if they are run beyond the "suggested service life" unless you run them dead.. (fuel contamination to crankcase)
Service life is based on a few things (including profit margins).. I personally figure if you are not working on stuff, you are not breaking or dropping stuff into the motor, tugging on wires or running a chance of disturbing stuff that was just fine to start with..
Some are fine with the extra work, I just prefer not to work on stuff that is not broke just yet
Most the cars I been driving over the past eight to ten years have a 100K check up. They all run fine and get great gas mileage to and beyond that point.
I think I was going about 10K on plugs for the Gen I, been told I could go much longer. At 8600 miles on the II and don't plan on changing them for a little while yet. Always ran the stockers.......
Many moons ago; late '70's the local shop had a small can on the floor. The mechanic took old plugs and pushed them into the top for a few seconds and placed the plugs back in the bike. I asked him about it and he said it was a little sand blaster they used to clean the plugs. Bet they charged for new ones ?
if the plugs are ready for change, typically 2 things will happen
fuel mileage will drop and hard starts will start happening.. other than that, there is no reason to change out a sparkplug.. they can not hurt an engine if they are run beyond the "suggested service life" unless you run them dead.. (fuel contamination to crankcase)
Service life is based on a few things (including profit margins).. I personally figure if you are not working on stuff, you are not breaking or dropping stuff into the motor, tugging on wires or running a chance of disturbing stuff that was just fine to start with..
Some are fine with the extra work, I just prefer not to work on stuff that is not broke just yet
I really have to agree with this line of thought and have heard similar comments from other members at gatherings.
Actually the coils can not tell what plugs are in the system... the secondary wires can.. (they must contain the increased voltage induced by the added resistance e/I*R)
the coils can not read resistance down stream in the secondary system as they are not even physically connected..
Primary current flows through a set of windings "around" another set of wound wires creating a magnetic field.. (close to each other but not connected, if they DO connect, the system dies)
When that primary field collapses around the secondary windings, it "induces" a secondary current (extreme high voltage) that goes down the secondary wires (plug wires or tower) to the plug..
If you have weak secondary ignition parts, they will break down from increased resistance at the plug (plug wire/tower arching)
Many of the "spark enhancers" of "better spark plug life" or "gas milage miracles" are simply "fixed gap" units that increase secondary voltage by introducing another "gap" the spark has to jump.. With todays ignition voltages hitting 60K+ just another waste..
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I put Iridiums in my bike at 12K miles. It never felt quite the same after that. It always started within a split second of hitting the starter button but with the iridiums it took several cranks. On cold starts there was a lack of power until the bike warmed up, it was as if a cylinder wasn't firing, but the idle was smooth with no missing. I take a trip every year along the same highway and would always get 49.6 mpg, same trip with the iridiums was around 46 mpg.
At 16K miles I noticed a lot more cranking time at start up and sometimes dying out after it started. I put the original 12K mile stock plugs back in and had instant starts and instant power from a stone cold engine, it was like brand new again and my mileage was back up to 49 on that highway. I left them in for the rest of the season and will be putting in a fresh set of standard oem plugs this spring.
Now....on my turbo Hondas the iridiums have been amazing. Stock these bikes came with Gold Palladiums which are $11 each from Honda and require replacing at 2K miles as per the Honda manual. So far I've put 5K miles on each bike with the iridiums and I'm seeing virtually no wear.
My CXTs love them and my Busa hates them. Who knows, maybe one of the iridiums in the Busa was never quite right from new but regardless it won't be getting another set. Busa isn't hard on plugs anyway and I have no problems replacing a stock set every 12K to 15K miles.
At 16K miles I noticed a lot more cranking time at start up and sometimes dying out after it started. I put the original 12K mile stock plugs back in and had instant starts and instant power from a stone cold engine, it was like brand new again and my mileage was back up to 49 on that highway. I left them in for the rest of the season and will be putting in a fresh set of standard oem plugs this spring.
Now....on my turbo Hondas the iridiums have been amazing. Stock these bikes came with Gold Palladiums which are $11 each from Honda and require replacing at 2K miles as per the Honda manual. So far I've put 5K miles on each bike with the iridiums and I'm seeing virtually no wear.
My CXTs love them and my Busa hates them. Who knows, maybe one of the iridiums in the Busa was never quite right from new but regardless it won't be getting another set. Busa isn't hard on plugs anyway and I have no problems replacing a stock set every 12K to 15K miles.
not the first time I have heard this, there are lots of guys that say fuel mileage dropped with the Iridium plugs... I have not seen this nor can I explain it unless there was a gap/heat range issue with the new plugs.. I would like to see a scope pattern on these bikes before and after... it is an odd thing for sure..
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