RTFM-ing for 8K maintenance

[2and3cylinders]

1 hour ago, nhchris said:

There is a rumor regarding our plugs:  They need to be spun loose every 8k miles so you can get em out when they really need to be replaced at say, 40k miles.

I know of no engine that needs plugs every 8k!

 So if you use copper anti seize on the plugs you can leave them in for 40000 lol

 I did an experiment with the iridium plugs and they ran fine and wore minimally but since they were the wrong reach, I took him out and put the oem spec plugs in. I did use spark plug indexing washers to orient the open side of the ground electrode facing the intake valves not that it probably matters much.

 I too have an ancient, I believe, motion pro mercury filled plastic tube on sheet metal 1 CM calibrated scale mounting board manometer, and a 2 channel electronic unit, the latter obviously not suitable for a CP3. I will pre check each tube on the same TB to verify they read the same and notated any variations (each tube hose has a "jet" in it to dampen pulsing and reduce mercury overall range).

At the first valve lash check at 20k miles all were very tight.  2nd check 15k later none had changed. So at 50k now and recuperating do I check them again along with the air filter, plugs and TB sync over the winter?

[piotrek]

1 hour ago, 2and3cylinders said:

So if you use copper anti seize on the plugs you can leave them in for 40000 lol

No need for any thread goop on modern spark plugs. NGK has a note about spark plugs on their site... first point talks anti-seize. I do remember the days...

[Buggy Nate]

1 hour ago, piotrek said:

No need for any thread goop on modern spark plugs. NGK has a note about spark plugs on their site... first point talks anti-seize. I do remember the days...

Yep as 👆. It probably stems from the days of motors having those god awful champion spark plugs. What an absolute pile of crap they are. I reckon I’ve drilled out about 30 of those bastards. 🤬

[tedski]

On 9/14/2021 at 8:09 PM, Buggy Nate said:

Yep as 👆. It probably stems from the days of motors having those god awful champion spark plugs. What an absolute pile of crap they are. I reckon I’ve drilled out about 30 of those bastards. 🤬

I think it's partly that and partly the newer coatings they put on the plug threads.  Simple advances in science and manufacturing.

[peteinpa]

On 9/11/2021 at 1:28 PM, thewrenchbender said:

Still have the budget set I got in the mid-80’s. Piece of fiberboard, four glass tubes stuck in a plastic reservoir w/an o-ring around the top holding it all together…

Got mine too, except mine is on a metal plate back ground.

Oooo that evil mercury...  Can't let the public have anything dangerous today.

I'll keep my plugs in for at least 16K miles.  When in there for the valves I'll change them then.

If memory serves my 83 650 Nighthawk wanted new plugs every 4k miles. 😵

[2and3cylinders]

On 9/14/2021 at 8:25 PM, piotrek said:

No need for any thread goop on modern spark plugs. NGK has a note about spark plugs on their site... first point talks anti-seize. I do remember the days...

OK, I should have known this but didn't.  They're website sucks though, on my cell at least, can't scroll down when searching for Yamaha, the whole screen slides up. On a PC it still isn't good.

Has anyone found a platinum or iridium plug that has the same reach etc as our OEM spec plug?

[micah2074]

On 9/14/2021 at 6:19 PM, nhchris said:

There is a rumor regarding our plugs:  They need to be spun loose every 8k miles so you can get em out when they really need to be replaced at say, 40k miles.

I know of no engine that needs plugs every 8k!

I can confirm that the rumor is BS 

[PhotoAl]

At MotoAmerica today talked with NGK representative.  They said reason for recommended interval is due to stress on upstream components not so much the plugs ability to fire.  Apparently as the plug ages it’s resistance goes up which puts more stress on the electrical components leading to the plug.  My take away is the coils will last longer if plugs are replaced on schedule.  
 

As I said earlier I still think my interval is reasonable due to the type of use my plugs have.

[thewrenchbender]

On 9/16/2021 at 11:21 AM, peteinpa said:

Got mine too, except mine is on a metal plate back ground.

Oooo that evil mercury...  Can't let the public have anything dangerous today.

I'll keep my plugs in for at least 16K miles.  When in there for the valves I'll change them then.

If memory serves my 83 650 Nighthawk wanted new plugs every 4k miles. 😵

Zero clue how a modern COP bike works, but old school bike plugs sparked every crank rotation-erosion wear would be sorta similar to 2x car plugs for the same miles.

My first Grand Marquis had coil blocks, 2 plugs fired ground-to-center 2 fired center-to-ground…

Would like to tell ya I’ve never played with mercury-can say with confidence I’ve never had the urge to ingest it.

[micah2074]

16 hours ago, PhotoAl said:

At MotoAmerica today talked with NGK representative.  They said reason for recommended interval is due to stress on upstream components not so much the plugs ability to fire.  Apparently as the plug ages it’s resistance goes up which puts more stress on the electrical components leading to the plug.  My take away is the coils will last longer if plugs are replaced on schedule.  
 

As I said earlier I still think my interval is reasonable due to the type of use my plugs have.

My 2015 has 110k+ miles on the clock and still runs as good as new. I change the plugs around 24k miles. Honestly, I think they could go quite a bit longer than that. 

[keithu]

18 hours ago, PhotoAl said:

At MotoAmerica today talked with NGK representative.  They said reason for recommended interval is due to stress on upstream components not so much the plugs ability to fire.  Apparently as the plug ages it’s resistance goes up which puts more stress on the electrical components leading to the plug.  My take away is the coils will last longer if plugs are replaced on schedule.  

That's the first logical explanation I've heard for the short plug interval. But given that almost nobody here ever reports ignition system problems I suspect the 8k interval is still overkill.