Your thoughts on When to change spark plugs?

[BLUEKNIGHT911]

Regarding coil failures. A fouled plug, will not destroy a coil. Simply, the energy travels to ground. A normal operation of a good plug, yes, the voltage required to fire the spark plug is determined by various factors. Compression ratio, BMEP, ignition timing, resistance of the plug, spark plug wire condition, resistance of the ground circuit, and more.

No doubt heat is bad for ignition coils, that heat will alter the resistance of primary and secondary segments of the coil itself.

Electronic ignitions, even battery ignitions or magnetos, do not like a high resistance or open high tension circuit. As resistance increases, the coils energy does best to be discharged. As resistance increases, the coil secondary windings can try to jump to the coils laminations. Other times, the windings will energize as the field collapses, and the path of least resistance will jump windings within the coil. Also, with these new COP setups, typically the plug resides in a deep cavity. There is a very short boot between to coil and plug. Since the boots position is between the resistor and coil, the misfire can deteriorate the rubber boot, burning it, and then misfiring to the metal ground of the cylinder head.

Regarding testing the plugs for resistance, typically the resistor is a carbon / graphite conductive material. Most commonly for powersports applications, that require resistor spark plugs, the value when new is 5-6 k ohms.

I have dealt with vintage motorcycle ignition issues, where 5k ohm spark plug caps had the carbon resistor ohm value increase to over 10k ohms. The higher resistance of the plug cap prevented the plug from firing at all. Swap the cap and starts in one kick.

We also deal with, and this is a serious problem, most of the spark plug manufacturers in the industry have stopped making non resistor plugs. Some owners, unaware there is a difference, have installed resistor plugs in ignitions not designed for them. Doing so results in various issues, most often, the ignition does not fire the plug, and in some cases, ruins ignition components.

Thanks for this info ..... How does it relate to our OEM plugs ???? ....Thanks ..... Mike

[PMK]

Thanks for this info ..... How does it relate to our OEM plugs ???? ....Thanks ..... Mike

Actually, very easily it relates to oem or aftermarket Spyder spark plugs. Technology of modern high performance spark plugs has far surpassed old school thinking that the appearance of a used spark plug determines the condition of the spark plug. Also hidden wear of a modern spark plug can very easily ruin parts that are far more expensive. Along with the slow degradation of engine efficiency should be avoided by replacing spark plugs with new spark plugs in a time frame or mileage similar to what is recommended by the engine manufacturer, vehicle manufacturer, or possibly the spark plug manufacturer.

Fully understanding the frugality that some owners enjoy regarding their Spyder, I have no issue at all with a person utilizing that opinion. My own actual experience contending with engines / vehicles that utilize COP technology and exotic metal spark plugs has had me replace more COP packs, spending hundreds of dollars to restore performance, efficiency, and reliability.

The wife’s previous Corolla began having coil and plug failures at just over 50k miles on plugs and COPs that are claimed 100k replacement intervals by the manufacturer. The V8 ford 5.4 litre, has now had several sets of spark plugs and 3 sets of 8 new COPs. The Ford was not pushed to extreme mileage before coils began failing. Typically, when one cylinder begins to misfire, other cylinders will fail shortly afterwards.

Learned my lessons years ago regarding COP setups in any vehicle, but as I mentioned, not concerned how others decide to maintain their vehicles.

[PMK]

Thanks for this info ..... How does it relate to our OEM plugs ???? ....Thanks ..... Mike

Wanted to add, regarding the Spyder, years ago, the oem spark plugs were replaced with Denso brand high performance spark plugs. Changed out the oem plugs at about mid life of the recommended replacement interval. No failures, just not a fan of NGK if possible. Prefer Densos and those went in.

[pegasus1300]

PMK please go into the differences between Denso and NGK. I used them both many years ago and found no real difference. Wondering what I missed.

[Cobwebs]

This from an NGK guy.

https://www.spyderlovers.com/forums/...=1#post1391772

[BLUEKNIGHT911]

This from an NGK guy.

https://www.spyderlovers.com/forums/...=1#post1391772

Thanks ..... He ( Gunner ) is still posting .... so I'll PM him and see how long His Plugs went ..... Mike .....PS - I don't know if you saw my CORRECTED plug mileage , but they are now at 80,626 mi. .....Mike

[svspyder]

Do you intend to do the work yourself? We've developed some shortcuts which reduce the time and effort needed for this service. We intend to do a video, but just haven't yet.

Ron, do the shortcuts eliminate the need to remove the frunk? In lieu of the video can you post a synopsis of the shortcuts you developed?

[IdahoMtnSpyder]

Ron, do the shortcuts eliminate the need to remove the frunk? In lieu of the video can you post a synopsis of the shortcuts you developed?

Based on my one-time experience, no you don't need to remove the frunk, but it probably makes the job easier. Maybe this will help you:

https://www.spyderlovers.com/forums/...ght=spark+plug

[Cobwebs]

Thanks ..... He ( Gunner ) is still posting .... so I'll PM him and see how long His Plugs went ..... Mike .....PS - I don't know if you saw my CORRECTED plug mileage , but they are now at 80,626 mi. .....Mike

Also shows your coils haven't gone completely south as well! I'm sure there would be variations from what you have achieved but can't see that it would be a massive difference even with variables of fuel quality, oil type, ambient temps, riding style etc. 28,000 is playing it safe from BRP's perspective I believe. Could be leftover thinking from the previous generation spark plugs still influencing peoples' decisions to not follow NGK's suggestions too.

Bosch have a multi ground plug that starts at 3000 ohms resistance that claims to extend the mileage and ignition component life even further again. What's next, wi-fi spark with no parts??

[BLUEKNIGHT911]

Also shows your coils haven't gone completely south as well! I'm sure there would be variations from what you have achieved but can't see that it would be a massive difference even with variables of fuel quality, oil type, ambient temps, riding style etc. 28,000 is playing it safe from BRP's perspective I believe. Could be leftover thinking from the previous generation spark plugs still influencing peoples' decisions to not follow NGK's suggestions too.

Bosch have a multi ground plug that starts at 3000 ohms resistance that claims to extend the mileage and ignition component life even further again. What's next, wi-fi spark with no parts??

Thanks for your comments ..... PS my mileage hasn't varied much in the last 70,000 mi. ....Except this past year it has actually risen by 1.5 to 2 MPG's ......Mike

[PMK]

Thanks ..... He ( Gunner ) is still posting .... so I'll PM him and see how long His Plugs went ..... Mike .....PS - I don't know if you saw my CORRECTED plug mileage , but they are now at 80,626 mi. .....Mike

Seems, being north of 80,000 miles, might as well run those spark plugs to 100,000 before changing them.

[BLUEKNIGHT911]

Seems, being north of 80,000 miles, might as well run those spark plugs to 100,000 before changing them.

As far as changing the plugs it came down to .... I'm getting older, and this will probably be the only time it will be done .... I'm down to about 5 to 6000 mi. per year now . I'll be 77 at the beginning of March - you do the math .....Mike

[PMK]

As far as changing the plugs it came down to .... I'm getting older, and this will probably be the only time it will be done .... I'm down to about 5 to 6000 mi. per year now . I'll be 77 at the beginning of March - you do the math .....Mike

Aren’t the experts stating 80 years old is the new 60? With your spunk, swagger, and New England codger, whether you change those plugs now or never, you and the Spyder will roll 100k. No math needed.

[Mikey]

Well Mike you got the easy part done and going to get a fresh set of plugs for free! Now roll your sleeves up and get going, we want to know what you find, and the most important thing will be is what you feel in the seat of your pants when you take your first ride on the old girl!!!

[old Timer]

Aren’t the experts stating 80 years old is the new 60? With your spunk, swagger, and New England codger, whether you change those plugs now or never, you and the Spyder will roll 100k. No math needed.

Heck yeah it's the new 60.........I'll be 81 next month, and I still ride my motorcycles and of course my Spyder ....er.... rather spiritedly on all over the local mountain and hill roads. Going for a nice Spyder today after it warms up a little more, will be in the mid to hi 50's within the hour.

[BLUEKNIGHT911]

Aren’t the experts stating 80 years old is the new 60? With your spunk, swagger, and New England codger, whether you change those plugs now or never, you and the Spyder will roll 100k. No math needed.

I'm not really concerned about the age of the plugs .....it's ME I'm concerned about .... I still do all my own wrenching, and the plugs takes a major panel removal to accomplish .....and while I'm in there I'll be replacing other maintenance items ..... Mike