Stelvio NGK Spark Plug Cap Replacement

[Steve350f]

OK, too much info out there on this and between AF1 and MG Cycle, there are 3 different NGK replacement numbers for the originals.  So, AF1 shows SB05E, and MG Cycle shows SD05F for original spark plugs & SB05F for replacement plugs with a threaded stud terminal.  If I stay with the original fixed terminal plug, should I be getting the SB05E or the SD05F?

I saw something about ordering both the NGK SB05E, and the also buying the SD05F to use that rubber boot on the SB05E. 

[Kiwi Dave]

Commonly-used replacement spark plug caps are the NGK SB05E.  Moto International (when they existed) recommended  NGK CR8EIX Platinum plugs with NGK SB05F spark plug caps.  I installed these on my Griso 1200SE which uses the same original caps as the Stelvio (I theenk!).

[wirespokes]

You can google image search for the NGK plug cap chart.

If Dave's data doesn't do it for you, or clarification is needed, here you go

https://www.google.com/search?q=NGK+cap+chart&client=firefox-b-1-d&tbm=isch&source=iu&ictx=1&fir=VDtTyeL2mbZ9sM%253A%252CJwiLp6BHdtp7MM%252C_&vet=1&usg=AI4_-kS1WOuu2FaO7DkDD-lkukGd-82j5A&sa=X&ved=2ahUKEwjgue-mkbToAhWDo54KHcfEB3gQ9QEwCHoECAcQEA&biw=1152&bih=636#imgrc=VDtTyeL2mbZ9sM:

[guzzisteve]

I just did 2 Stelvio's last year. You need both, the body for a post or threaded depending what plug you use AND the correct rubber to fit on insulator when installed. Figuring out the numbers is there.

[Lannis]

I saw something about ordering both the NGK SB05E, and the also buying the SD05F to use that rubber boot on the SB05E. 

That's exactly what I did to replace the busted boots on my Stelvio.   One model has the right electrical connection, the other has the right rubber bit.

It was hard for me to believe that the stock Stelvio plug boot was so fragile.   It FEELS like a quality, overbuilt, heavy-duty part, but everyone's boots seemed to be failing.

I guessed that some were failing from ham-handed removal - people just hauling on the wire to get the boot off and breaking the cable inside the boot.   I always gently pulled from the top, and levered it up with a screwdriver from the bottom ....

So I got two of the SD05F and two of the SB05E and put them in my glovebox and rode on.

The right side failed as I started it up in the morning to go to work ... the right side is an easy replacement because the cable length is just right.

About 2500 miles later, the left side failed as I was firing up the bike for a ride at the 2015 New Hampshire MGNOC National Rally.    That was a little tougher, as the left side cable has to be re-routed to reach the new boot fully - it's just about 1/2" short with stock routing but that bugger will NOT stretch!   But willing volunteer hands got up under the bike and sorted it in about 10 minutes.

Been good ever since.

Lannis

[Steve350f]

Wonder why both AF1 and MG Cycle wouldn’t explain this while selling these. 🤷‍♂️

[Lannis]

Wonder why both AF1 and MG Cycle wouldn’t explain this while selling these. 🤷‍♂️

Maybe it sounds like an "I heard it on the Internet so it must be true" bodge to them?   I'm sure they get a lot of that.

On the other hand, if I were a Moto Guzzi dealer, I would make it my business to read this list EVERY DAY.   You can certainly separate the technical Guzzi wheat from the chaff real quick to avoid wasting time, and there's no better way of getting a sense of what your (very small) customer base is thinking.   It's market research you can't possibly get any other way ....

Lannis