JamesW
JamesW
What do folks use, and how long do you run them. This is basically highway miles. I read an article somewhere that a lot of the specs in the owners manuals where EPA oriented.
Spark plugs
- Thread starter JamesW
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Geezer
Parsimonious Curmudgeon
Fairlaner
The Bartender Whisperer
Amazon has them for $28 a set.
R
R
Grumpy
Well-known member
Geezer
Parsimonious Curmudgeon
They are probably good for 100k miles. I saved the last set I took out because they looked like new. I may swap them back in this winter.
I had an old Cadillac which had plugs that were good for 100k. When I finally did need to change them one broke off and I had to pull off the head to get it out. So, now I use anti-seize and I pull them out once a year on all my vehicles that have aluminum heads. Every couple of years for iron heads.
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r1byker
Well-known member
I use the stock plugs and I just changed them with 22,000 miles on them. Did the TBS sync and mileage improved a couple mpg, bike is smoother at all rpm's, and it's easier starting. I guess it was about time.
bikesniffer
Well-known member
Just changed my Yamaha installed plugs after the first 14000miles, looked like brand new, popped CR8EIX's in, and keeping the ones I removed as spares.
Looks like spark plugs last for at least 25000 miles and the Iridiums prolly 50000miles...YMMV
Alfred
Looks like spark plugs last for at least 25000 miles and the Iridiums prolly 50000miles...YMMV
Alfred
olsonm3915
Well-known member
I can't find any on amazon for that price, cheapest I saw was $7.40 each ($29.40).
This guy, Nghia Thai, is selling them for a total of $26.70 ($23.75 + $2.95 shipping). Not affiliated, just a satisfied customer.
https://www.ecrater.com/product.php?pid=519...ngk+cr8eix+4218
I was a little leery of buying from the eCrater site, but I was able to use Google Checkout so I figured it was relatively safe.
See, if I'm going through the motions of pulling those plugs out every 16k miles (roughly every year) I'm sticking some new standard (non-iridium) plugs back in there. I can't see removing and installing used parts.
And I'm a cheap prick! Ask anyone...
Grumpy
Well-known member
I agree, the engine that Radio Howie has had these plugs in it for about 30k with absolutely no problems.
jim
johnny80s
Turtle Gears
Yup changed mine at 29k.
Grumpy
Well-known member
jmarran
Well-known member
He's at least half right!See, if I'm going through the motions of pulling those plugs out every 16k miles (roughly every year) I'm sticking some new standard (non-iridium) plugs back in there. I can't see removing and installing used parts.
And I'm a cheap prick! Ask anyone...
Oh, no. I'm 100% correct, no doubt. On this one I am sure.He's at least half right!
I'm the world's foremost expert on me.
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BkrK12
Well-known member
"See, if I'm going through the motions of pulling those plugs out every 16k miles (roughly every year) I'm sticking some new standard (non-iridium) plugs back in there. I can't see removing and installing used parts.
And I'm a cheap prick! Ask anyone... "
I'm with Fred on this one. Go to the trouble to take everything apart and then put the old plugs back in, when new standard plugs cost between $12 and $16, makes no sense.
And I'm a cheap prick! Ask anyone...
"I'm with Fred on this one. Go to the trouble to take everything apart and then put the old plugs back in, when new standard plugs cost between $12 and $16, makes no sense.
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Oh geeze.
I thought you were going to agree that I'm, a cheap prick... :blink:
I thought you were going to agree that I'm, a cheap prick... :blink:
ionbeam
2 FUN
Well, to
.......
As your spark plugs age in a high temperature, hydrocarbon enriched, high pressure environment they accumulate a carbon rich coating. Carbon is a partial conductor leading to high voltage leakage paths that bleed away some of the high voltage that should be contributing to spark intensity.
As the plugs age the sharp edges of the center electrode and ground electrode erode. When a plug is new, the ignition spark will seek out the most favorable area from which to arc. Over time this area erodes and the spark moves around to the next best arc location. As the plug continues to age the arc point becomes less and less favorable. Hold a spark plug up and look at it closely, squint and grunt as you look as hard as you can -- the plug still looks almost new. Take that plug to a microscope and look at the used plug's electrodes vs a new plug and you can see that the used plug's electrodes are indeed quite rounded causing poor arc ignition.
Your motorcycle still runs 'fine' and your butt dyno indicates that your bike runs as good now as when the plugs were new. Gas mileage doesn't seem to have changed.
Now give your plugs a real test. Go to your stone cold FJR, turn the key on and hit the starter. Your battery voltage sags as the starter spins, lowering the coil's secondary voltage. The ECU spikes the cylinders with a very rich dense fuel mixture. The engine is only being spun ~40 rpm by the starter. At this moment you call on your voltage leaking, eroded electrode plugs to perform one of the hardest tasks they can do -- start a cold engine. The amp sucking starter runs a bit longer, gets hotter than it normally would, the battery takes a bigger current hit. If it doesn't all work just right the plugs can get wet and then you have a no-start. Now the starter is hot, the battery is discharged and you are pissed...
If you are a go FAST type, consider your spark plug's task when you are asking for 9,000 rpm and maximum performance. At idle, 1,000 rpm, each pair cylinders are being fired once for each two engine revolutions, combustion in one cylinder and a waste spark in the other cylinder. The coil has an easy, leisurely job to recharge between each firing ensuring maximum voltage output at each discharge. At 9,000 rpm the coil has to try to recharge to full energy ~75 times each second. Under these conditions the coil output voltage usually falls off, right where you are looking for maximum power. Now cripple this with carbon leakage and unfavorable arcing at the electrodes.
If you have your plugs out just replace them and don't reuse them. If you have the tank up, the T Bar removed and you can access the plugs why not change them if they are at or over recommended change intervals for standard or iridium plugs.
As your spark plugs age in a high temperature, hydrocarbon enriched, high pressure environment they accumulate a carbon rich coating. Carbon is a partial conductor leading to high voltage leakage paths that bleed away some of the high voltage that should be contributing to spark intensity.
As the plugs age the sharp edges of the center electrode and ground electrode erode. When a plug is new, the ignition spark will seek out the most favorable area from which to arc. Over time this area erodes and the spark moves around to the next best arc location. As the plug continues to age the arc point becomes less and less favorable. Hold a spark plug up and look at it closely, squint and grunt as you look as hard as you can -- the plug still looks almost new. Take that plug to a microscope and look at the used plug's electrodes vs a new plug and you can see that the used plug's electrodes are indeed quite rounded causing poor arc ignition.
Your motorcycle still runs 'fine' and your butt dyno indicates that your bike runs as good now as when the plugs were new. Gas mileage doesn't seem to have changed.
Now give your plugs a real test. Go to your stone cold FJR, turn the key on and hit the starter. Your battery voltage sags as the starter spins, lowering the coil's secondary voltage. The ECU spikes the cylinders with a very rich dense fuel mixture. The engine is only being spun ~40 rpm by the starter. At this moment you call on your voltage leaking, eroded electrode plugs to perform one of the hardest tasks they can do -- start a cold engine. The amp sucking starter runs a bit longer, gets hotter than it normally would, the battery takes a bigger current hit. If it doesn't all work just right the plugs can get wet and then you have a no-start. Now the starter is hot, the battery is discharged and you are pissed...
If you are a go FAST type, consider your spark plug's task when you are asking for 9,000 rpm and maximum performance. At idle, 1,000 rpm, each pair cylinders are being fired once for each two engine revolutions, combustion in one cylinder and a waste spark in the other cylinder. The coil has an easy, leisurely job to recharge between each firing ensuring maximum voltage output at each discharge. At 9,000 rpm the coil has to try to recharge to full energy ~75 times each second. Under these conditions the coil output voltage usually falls off, right where you are looking for maximum power. Now cripple this with carbon leakage and unfavorable arcing at the electrodes.
If you have your plugs out just replace them and don't reuse them. If you have the tank up, the T Bar removed and you can access the plugs why not change them if they are at or over recommended change intervals for standard or iridium plugs.
Last edited by a moderator:
johnny80s
Turtle Gears
Man you like to fun all the fun out out everything.Well, to.......
As your spark plugs age in a high temperature, hydrocarbon enriched, high pressure environment they accumulate a carbon rich coating. Carbon is a partial conductor leading to high voltage leakage paths that bleed away some of the high voltage that should be contributing to spark intensity.
As the plugs age the sharp edges of the center electrode and ground electrode erode. When a plug is new, the ignition spark will seek out the most favorable area from which to arc. Over time this area erodes and the spark moves around to the next best arc location. As the plug continues to age the arc point becomes less and less favorable. Hold a spark plug up and look at it closely, squint and grunt as you look as hard as you can -- the plug still looks almost new. Take that plug to a microscope and look at the used plug's electrodes vs a new plug and you can see that the used plug's electrodes are indeed quite rounded causing poor arc ignition.
Your motorcycle still runs 'fine' and your butt dyno indicates that your bike runs as good now as when the plugs were new. Gas mileage doesn't seem to have changed.
Now give your plugs a real test. Go to your stone cold FJR, turn the key on and hit the starter. Your battery voltage sags as the starter spins lowering the coil's secondary voltage. The ECU spikes the cylinders with a very rich dense fuel mixture. The engine is only being spun ~40 rpm by the starter. At this moment you call on your voltage leaking, eroded electrode plugs to perform one of the hardest tasks they can do -- start a cold engine. The amp sucking starter runs a bit longer, gets hotter than it normally would, the battery takes a bigger current hit. If it doesn't all work just right the plugs can get wet and then you have a no-start. Now the starter is hot, the battery is discharged and you are pissed...
If you are a go FAST type, consider your spark plug's task when you are asking for 9,000 rpm and maximum performance. At idle, 1,000 rpm, each pair cylinders are being fired once for each two engine revolutions, combustion in one cylinder and a waste spark in the other cylinder. The coil has an easy, leisurely job to recharge between each firing ensuring maximum output at each discharge. At 9,000 rpm the coil has to try to recharge to full energy ~75 times each second. Under these conditions the coil output voltage usually falls off, right where you are looking for maximum power. Now cripple this with carbon leakage and unfavorable arcing at the electrodes.
If you have your plugs out just replace them and don't reuse them. If you have the tank up, the T Bar removed and you can access the plugs why not change them if they are at or over recommended change intervals for standard or iridium plugs.
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