Spark plugs

I don't think anyone's gotten enough mileage yet to worry about the plugs?

I may be wrong, but as for me, plugs are a change as needed, not change on a schedule item, unlike oil.

Mike
 
@ 10 000 miles give or take a few for me ... I am about to change mine when I do the 10 000mile valve check. Got them out at the time anyway ... so I may as well ;)


EDIT: I usually keep the old ones as emergency spares ... if they still look good

EDIT2: 4??? sorry I only have 2 :LOL:

EDIT3: NM I guess there are 4 ... what an odd place to put the other 2 on the bottom ... I totally missed that ... sigh
 
Last edited:
23,000 on original R18.

I will keep them until I can find a reason to replace them.

over 50,000 on the last set (4) I put in my R1200R.

Its like the effin gear oil. Lesser quality plugs last 100,000 miles in vehicles all the time. There is no lead in the gas.

I "rotate" my plugs every valve check, bottom to top. Both bikes.

David

It has used no oil.
 
Ulrich said:
@ 10 000 miles give or take a few for me ... I am about to change mine when I do the 10 000mile valve check. Got them out at the time anyway ... so I may as well ;)


EDIT: I usually keep the old ones as emergency spares ... if they still look good

EDIT2: 4??? sorry I only have 2 :LOL:

EDIT3: NM I guess there are 4 ... what an odd place to put the other 2 on the bottom ... I totally missed that ... sigh
Click to expand...
Ulrich, you swap your plugs out at 10k miles?!?! Are you running an airplane engine!!! 🤣🤣 j/k

Pump gas nowadays doesn't burn up plugs with properly tuned injectors like the carburetors of old. Even then, it was still possible to clean plugs that weren't damaged.

And yeah, our boxers are "Twin-spark" engines. The second plug is there apparently to burn the excess fuel that would have escaped out the exhaust pipe; a pseudo "emissions" control system of sorts, so BMW claims. But also the twin spark is also supposed to fix surging issues by ensuring complete combustion of fuel vapors in the chamber.

An aside: Twin spark and more are also used in aviation as redundant plugs, as well to prevent detonation with the leaded aviation fuel (yes...they STILL use leaded pump fuel at the airport/air strip for prop planes...)

https://www.bmwbmw.org/forums/viewtopic.php?f=14&t=11485
https://www.advrider.com/f/threads/what-is-twin-spark.432475/
https://www.motorbikestoday.com/news/Articles/BMW%20ignition.htm


Mike
 
Keehn said:
Ulrich, you swap your plugs out at 10k miles?!?! Are you running an airplane engine!!! 🤣🤣 j/k

Pump gas nowadays doesn't burn up plugs with properly tuned injectors like the carburetors of old. Even then, it was still possible to clean plugs that weren't damaged.

And yeah, our boxers are "Twin-spark" engines. The second plug is there apparently to burn the excess fuel that would have escaped out the exhaust pipe; a pseudo "emissions" control system of sorts, so BMW claims. But also the twin spark is also supposed to fix surging issues by ensuring complete combustion of fuel vapors in the chamber.

An aside: Twin spark and more are also used in aviation as redundant plugs, as well to prevent detonation with the leaded aviation fuel (yes...they STILL use leaded pump fuel at the airport/air strip for prop planes...)

https://www.bmwbmw.org/forums/viewtopic.php?f=14&t=11485
https://www.advrider.com/f/threads/what-is-twin-spark.432475/
https://www.motorbikestoday.com/news/Articles/BMW%20ignition.htm


Mike
Click to expand...
LOL ... this is my first 'modern' engine! ... with my Shovelhead I wouldn't leave home with a set of spares (and a spare set of points!) and a wrench with me ... I am still getting used to this ;)
 
Ulrich said:
@ 10 000 miles give or take a few for me ... I am about to change mine when I do the 10 000mile valve check. Got them out at the time anyway ... so I may as well ;)


EDIT: I usually keep the old ones as emergency spares ... if they still look good

EDIT2: 4??? sorry I only have 2 :LOL:

EDIT3: NM I guess there are 4 ... what an odd place to put the other 2 on the bottom ... I totally missed that ... sigh
Click to expand...
Reason I was asking work on cars some plug changes are 60000 miles and if you change them at that interval they don't like coming out 10000 miles will do me as well thanks👍
 
Alan neill said:
Reason I was asking work on cars some plug changes are 60000 miles and if you change them at that interval they don't like coming out 10000 miles will do me as well thanks👍
Click to expand...
Well I have to redo my whole thinking The BMW maintenance schedule calls for every 20 000 miles and I know that is (IMO) overly conservative knowing BMW ... so I think I go longer then and just check them every 10 000 :)
 
Ulrich said:
Well I have to redo my whole thinking The BMW maintenance schedule calls for every 20 000 miles and I know that is (IMO) overly conservative knowing BMW ... so I think I go longer then and just check them every 10 000 :)
Click to expand...
Okay...so this is getting ridiculous (currently researching my owners manual and google)...

The spark plug that BMW calls for is the "NGK MAR8AI-10DS" which is an Iridium-tipped plug. Anyone who's worked on cars knows that Iridium are practically the BEST kind of plugs you can get for longevity - they just don't wear out!

And yet, my Transcontinental manual wants me to REPLACE my IRIDIUM, yes...IRIDIUM spark plugs every 12k miles?!?!?! Are you "F"'ing kidding me!!!! Uhhhh....NO, I won't be doing that!

What I'll be doing instead is busting out my Fluke and doing ohmmeter checks on all four plugs. And, if all plugs check out at proper resistance spec, they'll go right back in Alcina! The "F"'ing WASTE in $$$ 🤬🤬🤬🤬

Sorry, I'm ranting here, but BMW is essentially asking us to throw out fine china to replace it with more fine china when there's nothing wrong with the original set. At 12k miles, Iridium plugs aren't even broken in yet! And this isn't a Japanese liter-bike, it's a low-RPM big boxer, so the plugs are seeing automobile-equivalent duty cycles ('ish).

I know that didn't help you at all Ulrich, but know that at least your shiny boxer has some super-strong Iridiums sparking the fuel inside the cans ;)

Mike
 
Keehn said:
Okay...so this is getting ridiculous (currently researching my owners manual and google)...

The spark plug that BMW calls for is the "NGK MAR8AI-10DS" which is an Iridium-tipped plug. Anyone who's worked on cars knows that Iridium are practically the BEST kind of plugs you can get for longevity - they just don't wear out!

And yet, my Transcontinental manual wants me to REPLACE my IRIDIUM, yes...IRIDIUM spark plugs every 12k miles?!?!?! Are you "F"'ing kidding me!!!! Uhhhh....NO, I won't be doing that!

What I'll be doing instead is busting out my Fluke and doing ohmmeter checks on all four plugs. And, if all plugs check out at proper resistance spec, they'll go right back in Alcina! The "F"'ing WASTE in $$$ 🤬🤬🤬🤬

Sorry, I'm ranting here, but BMW is essentially asking us to throw out fine china to replace it with more fine china when there's nothing wrong with the original set. At 12k miles, Iridium plugs aren't even broken in yet! And this isn't a Japanese liter-bike, it's a low-RPM big boxer, so the plugs are seeing automobile-equivalent duty cycles ('ish).

I know that didn't help you at all Ulrich, but know that at least your shiny boxer has some super-strong Iridiums sparking the fuel inside the cans ;)

Mike
Click to expand...
It did help ... btw. my R18 schedule calls for 20 000 (see the maintenance compilation that Scott made), but I am with you ... if it ain't broke don't fix it!!! and yes, it seems BMW is sure out to siphon as much coin as possible from folks that purchased their equipment ... I am not very fond of it! I bought this bike to outlive me ... but not at a cost (of maintenance) that I could have bought a couple other new bikes for 😆
 
Ulrich said:
It did help ... btw. my R18 schedule calls for 20 000 (see the maintenance compilation that Scott made), but I am with you ... if it ain't broke don't fix it!!! and yes, it seems BMW is sure out to siphon as much coin as possible from folks that purchased their equipment ... I am not very fond of it! I bought this bike to outlive me ... but not at a cost (of maintenance) that I could have bought a couple other new bikes for 😆
Click to expand...
My sentiments, exactly.... I never short out on new plugs for my Rotax 912 ULS in my airplane, and that's 1365 cc's with twin Bing 36 or 40 mm carbs running constantly at 5200-5500 rpm at 4.5 to 5.2 gallons of fuel per hour. I set the gap at .026" and in 400 hours, being checked annually, and treating the thread with heat sink paste, they've never gotten stuck in the motor, if torqued properly. I changed them at 400 hour, only because doing the annual I had them out and had already bought a new set, and they weren't even iridium. Iriidum plugs have gone 100,000 miles + in Ford Explorer V8's. The original plugs (two per cylinder) definitely give a more efficient burn and more HP than a single spark plug, more of the fuel air mixture gets burnt during combustion making power, as a result. A Mag check with rpm drop will confirm that, with motor under moderate load.

BMW is pretty blatant about their money grab, for those with any mechanical aptitude and experience.
 
Ulrich said:
LOL ... this is my first 'modern' engine! ... with my Shovelhead I wouldn't leave home with a set of spares (and a spare set of points!) and a wrench with me ... I am still getting used to this ;)
Click to expand...
Has anyone changed the lower set of plugs, the secondary ones? There appears to a single bolt holding the cover in place. However, once you have that out the cover still does not move. Any ideas or suggestions as to how to gain access?
 
Joost R1200CL to R18TC said:
Has anyone changed the lower set of plugs, the secondary ones? There appears to a single bolt holding the cover in place. However, once you have that out the cover still does not move. Any ideas or suggestions as to how to gain access?
Click to expand...
I took out the bottom plugs during my spring maintenance recently. The plastic cover (#5 in the microfiche below) just pulls out. The rear (closest to the engine body) of the plastic is a formed "C" that mates to a rubber grommet (#6 below). It simply pulls off and pushes back on, sort of like the side plastic covers that protect the ODBII port. Note in the microfiche that #6 has an angled groove that #5 fits into.

I don't particularly like this design tbh, because there's nothing but this single piece of plastic (and bolt) that secures the spark plug boot to the bottom plug. If it breaks, then there's no recourse but to buy another plastic "whatchamacallit" for $41.86 at current dealer prices.

1661257661714.png

Plus, I 100% disagree with the torque spec on these spark plugs (all four). When I pulled mine, the crush ring wasn't fully compressed. I retorqued to "gut-n-tight"...meaning until I knew all plugs were secure in their holes and ensure that zero blow-by occurs. In my 20+ years of "gut-n-tight", I've never once stripped a plug thread, so ymmv.

I also used some dielectric grease on the ceramic portions, as there was none present. Just peace of mind.

Mike
 
You must log in or register to reply here.
Back
Top