Check those plug tips

[Dave_in_TX]

It's been posted in other threads about the iridium tips on the 1250's spark plugs going missing due to erosion of the weld holding it on the electrode. I had this happen on my 2020 GS when I put the existing plugs back in after a 12k service. I thought it was only a problem when not replacing the plugs every 12k. However, on my 2023 GS, when a tip went missing in less then 12k, I switched to the dual electrode style plug used in the liquid cooled 1200s, even though I thought this might just be a freak occurrence. However, a recent post on advrider.com (https://www.advrider.com/f/threads/r-1250-engine-ngk-lmra8ai-10-spark-plug-failures-need-your-help.1712903/page-8#post-51356959) seems to indicate it's not as rare as I thought. I would recommend inspecting the plugs at much less mileage than 12k. You'll probably need a magnifying glass to check the the weld isn't eroding.

 

FWIW, I have been using the dual electrode plugs in my 2023 for about 27k miles and have not been able to detect any difference in fuel mileage or performance. The dual electrode plugs have a 0.8mm gap while the iridium plugs have a 1.0mm gap. However, I think the difference in gap between the 1200 and 1250 is due to the difference in plug construction, not because of any differences between the two engines and that 0.8mm is correct for the dual electrode plug in the 1250.. Fine wire electrode plugs like iridium require less voltage to fire, and there are usually benefits to a larger gap when the ignition system can support it, so I think BMW simply took advantage of this when going from the dual electrode in the 1200 to the iridium plug in the 1250.

[JCtx]

Did you have to re-gap those plugs? Or they come from the factory like that, and are specific to the 1200 LCs? Do you happen to have the P/N by any chance? I don't like how flimsy those iridium plugs are, and a fallen tip could cause a lot of damage, and my bike is a week away from losing the warranty. I might replace them sooner rather than later. Going on a short bike trip tomorrow (finally), and should come back with about 4K miles on the clock. Should I replace them now? Or until when? Thanks.

[Paddler]

I still can't believe BMW uses those plugs in their new bikes.  How embarrassing for them.  

I replaced mine with the dual electrode type in my 2020 R1250RS, didn't worry about the gap.  They work fine.

[Dave_in_TX]

8 hours ago, JCtx said:

Did you have to re-gap those plugs? Or they come from the factory like that, and are specific to the 1200 LCs? Do you happen to have the P/N by any chance? I don't like how flimsy those iridium plugs are, and a fallen tip could cause a lot of damage, and my bike is a week away from losing the warranty. I might replace them sooner rather than later. Going on a short bike trip tomorrow (finally), and should come back with about 4K miles on the clock. Should I replace them now? Or until when? Thanks.

The dual electrode plugs come gapped at 0.8mm. I'm running LMAR9D-J but the standard heat range LMAR8D-J should work fine too.

 

Should you replace them now? That's up to you. All I can tell you is not to trust the iridiums without periodically inspecting them.

[Joe Frickin' Friday]

19 hours ago, Dave_in_TX said:

You'll probably need a magnifying glass to check the the weld isn't eroding.

 

Everybody needs an Optivisor:

https://www.amazon.com/Donegan-Optical-OptiVISOR-Headband-Magnifier/dp/B0068OSIIS

 

I was using one of these before my eyes ever hit middle-age and turned to crap.  Very handy.   Get a variety of lenses so you can be ready for different viewing needs.

 

Thanks for starting this thread and sharing the ADVRider thread.  having read through both, I'm pretty shocked at how bad those iridium plugs are behaving.  My 2023 1250RT has just over 5K on it; I think I'll look at swapping out the plugs when I do the 6K oil change.

 

 

[rounder jim]

I have been running these iridium plugs for 108,000 miles now and have never seen the iridium tip fall off or be worn to nothing.  My wife"s 2018 Honda Accord, Touring ,2 liter, comes with NGK Iridium  (DILKAR8P8SY)..  The recomended service interval on this car is 100k. I replaced the plugs this weekend at 64K because 4 plugs cost less than $30 and the job took me less than 35 minutes. The iridium tips looked fine but I was surprised at the dark color of the plugs. Much darker than the nearly white color of the plugs coming out of my 22 Triple Black RT. 

   I am not an engineer . I trust Honda"s and BMW's engineers to put what they feel is the best plug in my engines

[Dave_in_TX]

1 hour ago, rounder jim said:

I have been running these iridium plugs for 108,000 miles now and have never seen the iridium tip fall off or be worn to nothing.  My wife"s 2018 Honda Accord, Touring ,2 liter, comes with NGK Iridium  (DILKAR8P8SY)..  The recomended service interval on this car is 100k. I replaced the plugs this weekend at 64K because 4 plugs cost less than $30 and the job took me less than 35 minutes. The iridium tips looked fine but I was surprised at the dark color of the plugs. Much darker than the nearly white color of the plugs coming out of my 22 Triple Black RT. 

   I am not an engineer . I trust Honda"s and BMW's engineers to put what they feel is the best plug in my engines

Are you saying you have been running the LMAR8AI-10 for 108000 miles in a 1250? Not everyone seems to have a problem with them but they don't seem to have the durability of other iridium plugs.

[JCtx]

My guess is he's been reusing them, so not just 1 pair. For what I've seen on this forum, there's no way the engine would even run with half that mileage. So let's wait for Jim to respond, but no way in hell I'd leave them even for 12K miles. I'm going to order the much sturdier (and more reliable) dual-plug ones shortly, and change them at 4K miles. Seems to me bikes use more powerful coils, which eat up plugs much quicker than cars. Not sure there's any other explanation.

[MikeB60]

He is referring to the iridium plugs in the Honda Accord. 

[Dave_in_TX]

11 hours ago, JCtx said:

My guess is he's been reusing them, so not just 1 pair. For what I've seen on this forum, there's no way the engine would even run with half that mileage. So let's wait for Jim to respond, but no way in hell I'd leave them even for 12K miles. I'm going to order the much sturdier (and more reliable) dual-plug ones shortly, and change them at 4K miles. Seems to me bikes use more powerful coils, which eat up plugs much quicker than cars. Not sure there's any other explanation.

If you're switching to the dual electrode [lug, there's no need to switch them out at 4k. NGK says they're good to 50k in auto applications

[JCtx]

I'm going to switch TO the dual-electrode LMAR8D-Js for the first time, at around 4K miles. I just want those potentially dangerous stock LMAR8Ai-10s out of there. Apparently there's no need to order coil extractors, with only 4K miles. If somebody had an issue removing the coils with just your fingers, and I need an extractor tool, please post which one I need to buy. Thanks gang.

[Dave_in_TX]

5 hours ago, JCtx said:

I'm going to switch TO the dual-electrode LMAR8D-Js for the first time, at around 4K miles. I just want those potentially dangerous stock LMAR8Ai-10s out of there. Apparently there's no need to order coil extractors, with only 4K miles. If somebody had an issue removing the coils with just your fingers, and I need an extractor tool, please post which one I need to buy. Thanks gang.

I doubt you'll be able to pull the coils by just using your fingers. You can use two flat bladed screwdrivers to pry them loose. Put a rag between the screwdrivers and valve cover to avoid scratches.

[Rougarou]

I've been using these forever.  Put the tips in the coil wedges/indentations and use the head as leverage.  Coil slides right out.

 

[JCtx]

Somebody here told me he did it with just his fingers. But after your post, rather have the proper tool. Any idea where to buy it? Hopefully they're not too expensive, as I'll probably use it just once or twice. Thanks.

[Rougarou]

10 minutes ago, JCtx said:

 rather have the proper tool.

 

The proper tool is the one that gets the job done and it doesn't have to be the specifically designed tool for the purpose. 

[Dave_in_TX]

6 hours ago, JCtx said:

Somebody here told me he did it with just his fingers. But after your post, rather have the proper tool. Any idea where to buy it? Hopefully they're not too expensive, as I'll probably use it just once or twice. Thanks.

A Google search for bmw coil puller shows them available at ebay, Amazon, and Sierra BMW, as well as others. Ebay appears to be cheapest.

[JCtx]

Hey, thank you very much for your help. Found several on Amazon, but went with the only one with 5 stars, so avoid any potential issues, and it's a reasonable $13, so not worth looking elsewhere. Here it is, in case somebody else wants it too: https://www.amazon.com/gp/product/B0BJVBNC5C/ref=ox_sc_act_title_1?smid=AUVSHH72YEZ2Z&psc=1. Thanks again for your help. Have a great weekend ahead.

[Rougarou]

Let's do realtime plug change

 

 

 

 

[rounder jim]

I'm sorry people, We've been busy getting ready for our Florida ride with the stop at Barber for vintage cycle racing and I neglected to go back to the site.NO these plugs have not been in the bike for 108k . A new set is installed every 18k. But after reading  about people having trouble with the tips I'm going back to 12k intervals.

[Rougarou]

On the left is 60k worth of miles on plugs from the ‘06 RT. On the right is 24k worth of miles from the ‘19 GSA

 

Different bikes and slightly different plugs, but the burn is equal. 
 

So tell me again why 12k is the standard change. I think 18 or 24k is the change for the RT

 

 

This recent set, ill likely go 50k or so before changing on the GSA

[Dave_in_TX]

15 hours ago, Rougarou said:

So tell me again why 12k is the standard change. I think 18 or 24k is the change for the RT

 

 

I always went with 24k plug changes on my 2007 and 2011 RTs and my 2014 GS (dual electrode plugs).

[Toter]

The plugs used in an 06 RT and their longevity has no bearing on the original discussion for the current generation R1250's. I have pulled plugs on two different 1250's and found results like this at 12k miles. I don't plan to leave them in my 22 GSA until 12k. I will probably switch to the dual electrode plugs. These were out of a 23 GSA at 12,100 miles. YMMV

[Rougarou]

8 minutes ago, Toter said:

The plugs used in an 06 RT and their longevity has no bearing on the original discussion for the current generation R1250's. I have pulled plugs on two different 1250's and found results like this at 12k miles. I don't plan to leave them in my 22 GSA until 12k. I will probably switch to the dual electrode plugs. These were out of a 23 GSA at 12,100 miles. YMMV

 

Plug on the right is out of a 2019 GSA (that's a 1250) with 24k (on the plug), plug on left, brand new.  Only difference is color, tip looks just fine.  The point bringing up the '06 was the "book recommendation" compared to actual real world change with a plug with 60k miles "on the plug"

 

 

I wished I'd kept the original plugs changed at 20k miles as they looked the same and prolly coulda went to the 44k I just did.

 

Two changes of plugs in 44k miles.  Neither sets of plugs warranted a change.  Others results may differ.

 

 

 

[Toter]

2 minutes ago, Rougarou said:

 

Plug on the right is out of a 2019 GSA (that's a 1250) with 24k (on the plug), plug on left, brand new.  Only difference is color, tip looks just fine.  The point bringing up the '06 was the "book recommendation" compared to actual real world change with a plug with 60k miles "on the plug"

 

 

I wished I'd kept the original plugs changed at 20k miles as they looked the same and prolly coulda went to the 44k I just did.

 

Two changes of plugs in 44k miles.  Neither sets of plugs warranted a change.  Others results may differ.

 

 

 

The plugs I have seen eroded were BMW  branded. I see yours are std NGK. Maybe the OEM plugs are cheaply made???

[Rougarou]

6 minutes ago, Toter said:

The plugs I have seen eroded were BMW  branded. I see yours are std NGK. Maybe the OEM plugs are cheaply made???

 

Ya, I don't remember the brand of the original plugs I pulled at 20k, they were original to the bike from the factory.

 

They were probably NGK as that's what the book "recommends"

 

[Dave_in_TX]

2 hours ago, Toter said:

The plugs I have seen eroded were BMW  branded. I see yours are std NGK. Maybe the OEM plugs are cheaply made???

I have seen eroded NGK and BMW plugs. I'm willing to bet that the BMW plugs are simply rebranded NGK. In fact, the BMW branded ones carry an NGK designation (LMAR8AI-10).

[Toter]

1 hour ago, Dave_in_TX said:

I have seen eroded NGK and BMW plugs. I'm willing to bet that the BMW plugs are simply rebranded NGK. In fact, the BMW branded ones carry an NGK designation (LMAR8AI-10).

Just thought they might be lesser quality as you see with tires on a new car having lower spec than the same tire you buy aftermarket. But, if you've seen it on both, it is either an NGK issue, or something with the bike. Detonation/spark knock can do that, and unfortunately,  a lot more damage.

[KDeline]

On 10/12/2024 at 6:07 PM, Dave_in_TX said:

I always went with 24k plug changes on my 2007 and 2011 RTs and my 2014 GS (dual electrode plugs).

 On 10/12/2024 at 1:29 PM, Rougarou said:

So tell me again why 12k is the standard change. I think 18 or 24k is the change for the RT

 

I'm from a different mindset, and called foolish but..... I have never changed a regular large electrode single or dual plug with less then 80000 miles. Yup you read it right and I still could have continued to use them. At around 12 to 15 thousand miles I just adjust the plugs electrode with a whack on the cement floor, measure, and reinstalled. Never in 1.2 million BMW miles has one failed. Went to the dual plug on the 2022 shiftcam because of the problems showing up on some of these small wire electrode plugs. I understand the small plugs but what has changed in the large electrode plugs that require constant changing instead of a simple adjustment? And don't get me started on longevity of oil..... Be gentle. 

[Dave_in_TX]

14 hours ago, KDeline said:

 On 10/12/2024 at 1:29 PM, Rougarou said:

So tell me again why 12k is the standard change. I think 18 or 24k is the change for the RT

 

I'm from a different mindset, and called foolish but..... I have never changed a regular large electrode single or dual plug with less then 80000 miles. Yup you read it right and I still could have continued to use them. At around 12 to 15 thousand miles I just adjust the plugs electrode with a whack on the cement floor, measure, and reinstalled. Never in 1.2 million BMW miles has one failed. Went to the dual plug on the 2022 shiftcam because of the problems showing up on some of these small wire electrode plugs. I understand the small plugs but what has changed in the large electrode plugs that require constant changing instead of a simple adjustment? And don't get me started on longevity of oil..... Be gentle. 

I'm not an expert but from what I have read, gap isn't the only thing to be concerned with. Supposedly, as a plug wears, the sharp edges on the electrodes become rounded resulting in a plug that produces a less effective apark.

[KDeline]

49 minutes ago, Dave_in_TX said:

I'm not an expert but from what I have read, gap isn't the only thing to be concerned with. Supposedly, as a plug wears, the sharp edges on the electrodes become rounded resulting in a plug that produces a less effective apark.

Maybe something to that and mine have rounded but I adjust and all seems well. May bite me in the butt some day. I do carry spare plugs when I travel for that reason. 

[Dave_in_TX]

4 hours ago, KDeline said:

Maybe something to that and mine have rounded but I adjust and all seems well. May bite me in the butt some day. I do carry spare plugs when I travel for that reason. 

Those well worn plugs may also be making your coils work harder.

[KDeline]

17 minutes ago, Dave_in_TX said:

Those well worn plugs may also be making your coils work harder.

With what little knowledge I have about that in particular, I would think if the gap was correct there would be no extra power needed by the coil. My understanding it is as the gap gets larger to create the spark. 
 

[Joe Frickin' Friday]

1 hour ago, KDeline said:

With what little knowledge I have about that in particular, I would think if the gap was correct there would be no extra power needed by the coil. My understanding it is as the gap gets larger to create the spark. 

 

It turns out that electrical arcs like to jump from features with a small radius of curvature.  This means sharp points and edges.  You certainly can get an arc to jump from a flat surface or a smooth large-diameter sphere, but it'll take more voltage to get that arc started.  If you watch a spark plug in action, you'll see that the spark wants to jump from the sharp circular edge of that center electrode instead of the flat central plateau, even though that edge may not be any closer to the ground electrode.  Over time that sharp edge of the center electrode gets eroded away, increasing its radius of curvature, and yes, your coil will then have to tolerate a bit higher voltage to create each spark.   As to how much more voltage, and how hard that might be on the coils (i.e. how much bigger the risk of blowing a coil might be), I couldn't say.  @Dave_in_TX brought this up, so maybe he's got some experience with this?  

[KDeline]

5 minutes ago, Joe Frickin' Friday said:

 

It turns out that electrical arcs like to jump from features with a small radius of curvature.  This means sharp points and edges.  You certainly can get an arc to jump from a flat surface or a smooth large-diameter sphere, but it'll take more voltage to get that arc started.  If you watch a spark plug in action, you'll see that the spark wants to jump from the sharp circular edge of that center electrode instead of the flat central plateau, even though that edge may not be any closer to the ground electrode.  Over time that sharp edge of the center electrode gets eroded away, increasing its radius of curvature, and yes, your coil will then have to tolerate a bit higher voltage to create each spark.   As to how much more voltage, and how hard that might be on the coils (i.e. how much bigger the risk of blowing a coil might be), I couldn't say.  @Dave_in_TX brought this up, so maybe he's got some experience with this?  

And that is what I did not know..... How do the cars seem to have such a high mileage plug change?  May have to rethink my plug intervals.

[Hosstage]

Cars have such a long interval on plug changes because they cost so much to have changed. People would be quite put out to have to pay for that every other oil change. So "No, they're fine, they'll go 100,000 miles no problem."

[Joe Frickin' Friday]

13 minutes ago, KDeline said:

And that is what I did not know..... How do the cars seem to have such a high mileage plug change?  May have to rethink my plug intervals.

 

Speculating here, but if worn/rounded plug electrodes really do put significantly more stress on the coils, then maybe automotive coils are built a bit tougher to tolerate that, so that they can go 100K miles without blowing a coil.  That would be consistent with what @Hosstage suggested, i.e. the average car owner won't put up with a maintenance-intensive vehicle.  

 

[Dave_in_TX]

11 hours ago, KDeline said:

And that is what I did not know..... How do the cars seem to have such a high mileage plug change?  May have to rethink my plug intervals.

For one thing, car engines usually operate at a much lower RPM than bikes. Plug life is related to how many times it fires, not directly to miles driven. Also, many bikes fire their plugs twice per cycle (simpler ignition operation), I don't think this is common in autos.

 

 

[Joe Frickin' Friday]

4 hours ago, Dave_in_TX said:

For one thing, car engines usually operate at a much lower RPM than bikes. Plug life is related to how many times it fires, not directly to miles driven. Also, many bikes fire their plugs twice per cycle (simpler ignition operation), I don't think this is common in autos.

 

 

I know the oilheads used to fire plugs and injectors on every crank revolution.  That eliminated the need for a cam position sensor.  Don't know what the hexhead bikes did.  On our shiftheads, there's certainly a cam sensor, since the computer knows when to stick its finger into the machinery to switch cam lobes; it would be simple to use that information to only fire the plugs just before a power stroke (and not before the start of an intake stroke), but I have no idea whether BMW has done this or not.  

 

[Dave_in_TX]

On 10/1/2024 at 2:59 PM, JCtx said:

I'm going to order the much sturdier (and more reliable) dual-plug ones shortly, and change them at 4K miles. Seems to me bikes use more powerful coils, which eat up plugs much quicker than cars. Not sure there's any other explanation.

I just changed out a pair of LMAR9D-J that had 36k miles on them. Gap had increased form .8mm to 1mm. I'll probably leave the new set in for 36k also.

[JCtx]

Man, that's great news. And zero worries about them breaking up inside our engines. Haven't used my bike since installation, but have no doubt there won't be any differences. Thanks again for the recommendation.