GSW Spark Plug

[huairen]

Is there an Iridium Spark Plug for the GSW 2013+ available?
Was thinking of using iridium instead of the standard plugs.

 

[Grim Reaper]

The only plug available so far as I can see is the NGK LMAR8D-J
If you can find an equivalent let us all know.

 

[Neil W]

I tried Iridium plugs in a range of cars and bikes and came to the following conclusion after a good few miles, if you fit iridium plugs in an older vehicle with points ignition or earlier cdi ignition and carburettors or early mechanical injection systems they will cause a very noticeable improvement in starting, tickover and general performance.

Iridium plugs in newer stuff , including the r1150 / 1200 motors with fuel injection and a decent ignition system may last longer but have no significant difference to the machines overall performance and unless you can get them really cheap are probably not worth fitting

 

[Nick V]

The only plug available so far as I can see is the NGK LMAR8D-J
If you can find an equivalent let us all know.

If you habitually run the bike hard, you could also make use of LMAR9D-J plugs - these are used in the S1000RR and HP4. It's exactly the same plug as LMAR8D-J, just one heat range colder.
But buying it through BMW, there will be no price advantage at all.

There is also the LMAR9E-J. As far as I could tell, it's used in certain Yamaha R1s. The only difference between this plug and LMAR9D-J is that the E-J has a screw-on terminal instead of a clip-on terminal. No problem - just get two terminal ends from your friendly neighbourhood maccy, and you've got plugs you can use in the LC.
It's also a part on which a motor manufacturer has no monopoly (unlike BMW). So there may be a price advantage there.

I scoured the NGK and Denso catalogues a while back - I found loads of 10mm-threaded iridium plugs with a 19mm reach, but none with a 26.5mm reach.
If anyone finds something I missed, don't be shy to spread the love!

I tried Iridium plugs in a range of cars and bikes and came to the following conclusion after a good few miles, if you fit iridium plugs in an older vehicle with points ignition or earlier cdi ignition and carburettors or early mechanical injection systems they will cause a very noticeable improvement in starting, tickover and general performance.

Iridium plugs in newer stuff , including the r1150 / 1200 motors with fuel injection and a decent ignition system may last longer but have no significant difference to the machines overall performance and unless you can get them really cheap are probably not worth fitting

IMHO, if iridium plugs are available, fitting equivalent nickel steel plugs is a false economy. (Admittedly, the bottom-line figures are pretty close.)
I don't know if the situation is different in the UK, but to use a typical South African example, NGK DCPR8E plugs are around R90 each. DCPR8EIX plugs (iridium version of exactly the same plug) are around R120 each.

Given that DCPR8Es will last about 10 000 Km, that works out to 0.9 cents/Km/plug.
Given that DCPR8EIXs will typically last at least three times longer, that works out to a maximum of 0.4 cents/Km/plug. Some platinum and iridium plugs used in high-performance cars have QUOTED lives of 100 000 Km or more. Being conservative and simply doubling the replacement interval to 60 000 Km yields 0.2 cents/Km/plug.

 

[Smug]

I spoke to NGK technical and supposedly they don't plan to make a iridium plug for the LMAR9D-J

 

[Nick V]

Excellent news!

As the subject line says.

I did some much deeper digging, and by my latest count, there are at least nine NGK spark plugs available which are suitable for the 1 170 cm3 liquid-cooled boxer-twin (in terms of having 10mm thread diameter and 26.5mm reach).
Four of those nine use iridium electrodes.

This is the list of NGK iridium plugs I've found so far:
- LMAR9AI-8 (fitment to KTM 350 SX-F)
- LMAR9AI-10 (fitment to KTM Freeride 350)
- SILMAR9A9S (fitment to Honda CRF 450R)
- SILMAR10A9S (the same plug as above, but one heat-range colder. I wouldn't recommend these for WC engines tuned for the road - they would likely foul with carbon).

CAVEAT! I make no representation that any of these plugs will not fry, boil, blanche, saute, flambee or otherwise wreak havoc with your engine.
There is no good reason why any of them should, but as always, you step outside factory recommendations at your own risk.

Detailed specs are as follows:

LMAR9AI-8:
Thread Size: 10mm
Hex Size: 9/16" (14.3mm)
Reach: 26.5mm (1.04")
Seat Type: Gasket
Gap: .032" (0.8mm)
Heat Range: 9
Terminal Type: Solid
Resistor: Yes
Brand: NGK
Center Electrode:
Type: Fine Wire
Material: Iridium
Ground Electrode:
Type: Standard
Material: Platinum
Quantity: 1

SILMAR9A9S:
Thread Size: 10mm
Hex Size: 14mm
Reach: 26.5mm (1.04")
Seat Type: Gasket
Gap: .036" (0.9mm)
Heat Range: 9
Terminal Type: Solid
Resistor: Yes
Thread Pitch: 1.0mm
Brand: NGK
Center Electrode:
Type: Fine Wire
Material: Iridium
Projection: Projected
Ground Electrode:
Type: Taper Cut
Material: Platinum
Quantity: 1

SILMAR10A9S:
Thread Size: 10mm
Hex Size: 14mm
Reach: 26.5mm (1.04")
Seat Type: Gasket
Gap: .036" (0.9mm)
Heat Range: 10
Terminal Type: Solid
Resistor: Yes
Thread Pitch: 1.0mm
Brand: NGK
Center Electrode:
Type: Fine Wire
Material: Iridium
Projection: Projected
Ground Electrode:
Type: Taper Cut
Material: Platinum
Quantity: 1

 

[ATG]

Nick;

Indeed great news !

I wonder: HAve you tried any of these on the GSW ? If so, which and with what kind of results ? Is your GSW standard or did you make any engine mods ?

Personally I have a 2014 GSW with Rhemus cat less and valve less headers and Akrapovic (BMW HP) silencer. I use a booster to increase (lower) the air fuel ratio.

I would be greatly interested to share your experience ! Please report.

Best regards,

Andre

 

[Nick V]

I wonder: HAve you tried any of these on the GSW ? If so, which and with what kind of results ? Is your GSW standard or did you make any engine mods ?
Personally I have a 2014 GSW with Rhemus cat less and valve less headers and Akrapovic (BMW HP) silencer. I use a booster to increase (lower) the air fuel ratio.
I would be greatly interested to share your experience ! Please report.

Hi Andre!

I haven't tried any of these plugs on my bike yet as I still have about 6 months left of the warranty period.
If my bike has to go into a BMW workshop for any reason and the mechanics spy anything other than the standard plugs in there, that warranty will be history faster than you can believe (and since I'm due for a replacement rear tyre-pressure sensor and upper steering triple-clamp bearing, the remainder of the warranty is not something I'm keen to lose.)

At the moment, the bike is completely standard, but a setup very similar to yours is on the cards for some time in the mid-future.

When it comes time to change my own plugs for iridium ones, availability will play a big part in my choice. Here in SA, you can't just find out about a plug you like, then go out and buy it. Most guys who man parts stores here seem terminally stupid, and if you mention any spark plug they don't handle on a daily basis, you can literally watch them struggling to think.
Also, with our weak exchange rate, it costs retailers money to sit with stock of exotic plugs on their shelves. So if it's stock they can't shift a lot of, they simply won't order them.

Personally, I would have no reservations about using the LMAR9AI-8 (heat range 9, 0.8mm air gap) or SILMAR9A9S (heat range 9, 0.9mm air gap).
Interestingly, the LMAR9AI-8 is almost exactly the same plug used in the K1600 six-cylinder bikes. It's just one heat range colder.
So my list is incomplete - you could also use the LMAR8AI-8. Sit down before you hear the price, though - they're listed on the Max BMW site for US$22.10 each. (You could probably get them cheaper from a good automotive parts store).

The LMAR9AI-10 has a 1.0mm air gap which, in my opinion, is excessive. The SILMAR10A9S has a heat range of 10 (two heat ranges colder than standard). It might be a great plug if you were running an LC at Interlagos , but for everyday riding, you might get problems with cold starts and low-speed running.

 

[ATG]

Hi Nick;

I wanted to send you a private message, however, for some reason the UKGser doesn't allow me to do so...

Perhaps we may communicate through email ? My address is:

[email protected]

Please write me your address so I can share some information I gathered.

Andre

 

[Nick V]

Hi again Andre,

No problem! I'll send you a mail from my address.

 

[ATG]

Hi Nick;

Send you an email (reply to your's) on the 19th and I wonder if you received it ?

If not let me know and I will send it again.

Merry Christmas !

Andre

 

[Nick V]

Hi Andre! I replied to your E-mail some time ago.
How are the new plugs going? Any feedback as yet?

 

[ATG]

Hi Nick;

Sorry... I saw your email while I was travelling and when came back had forgotten to answer it. Sorry again.

The plugs are working fine. I have riden some 2000 Km since installing them and find the improvement small but worthwhile.

Best regards,

Andre