Stelvio and 8V Spark Plug Caps. Need NGK SB05E

[leafman60]

I suppose you could use the CR8EIX iridium plugs with the SD05F caps. Those plugs have the screw-on terminals (or come with removable push-on terminals, at least). Does the SD05F fit under the removable cover or do you have to leave that off?

 

Oh, the SD05F looks just like the SB05E.  Scroll up and look at the pics.  It will fit just fine. The only difference is that the SD is for screw-on and the SB is for push-on.  

These are straight caps and the wires bend over to align them with the plugs.

[John Warner]

Decided to do my Caps today, went a slightly different route (pretty normal for me!).

Used NGKs Red all-rubber Caps~


Cut the leads right at the ends to give maximum length.

I pulled the New Caps internals out, hoping to fit the original in the sleeve, but it was too loose.

New cap sticks out a bit as you can see, but the upper 30mm or so is just an empty sleeve, the fitting the lead screws into is far enough down for the top to fold over easily, so it fits under the plastic cover.

[leafman60]

Bump upon request.

[Lannis]

Perhaps you could change to different terminals.  I cant see why the terminal design alone would make a difference if the other plug parameters are the same.

The SD05F caps will not fit the terminals of the stock Stelvio NTX sparkplugs. 

The sparkplugs have the push-on terminals and the SD05F fits the screw-on terminal plugs.  SB05E fits the push-on terminal plugs but the rubber boot is too big. 

To do it right, you get the SB05E so the cap will fit the plug and you get the SD05F for the correct size weather boot to use on the SB05E cap  Got it ?  Complicated but they are not expensive.

NGK doesn't import the proper cap with the proper weather seal which would be the SD05E in NGK nomenclature.

Just to experiment, I bought a pair of SB05E and a pair of SD05F and put them in my fairing pocket, to see how far the originals would go.   Is the weakness of the originals an urban legend or not?   

The left side (the hardest one to replace because you have to shift a fairing piece to reroute the wire) went bad at last year's National in New Hampshire, right in the fairground, so we had a bit of tech session to replace it.   33,000 miles.

The right side went bad just as we started a 2500 trip with friends.   Took 5 minutes, 40,500 miles.

That amazes me, since the OEM boots LOOK and FEEL like they're the toughest, heaviest spark plug boots ever made.   Obviously, however, they are not - someone screwed up the design on these, one of the simplest and longest-used functions in automotive history, and it's Japan Incorporated to the rescue ....

Lannis

[Wayne Orwig]

Simple. They are too hard to pull. And they have a rubber 90 degree bend. So the rubber gets cracked right below the 90 because people tend to pull on the wire and bend the and crack the rubber. Which is where the wire terminal is. So you get an arc once the crack opens up enough and humidity or such sends the voltage a few volts higher.

When my originals final, I replaced them with originals under warranty. I remove the replacements with care (never bend that 90). Those have about 50,000 miles now.

If they reduced the pull, we wouldn't have issues. If they double insulated the terminal so it didn't arc if it cracked the rubber elbow, we wouldn't have issues.

[Lannis]

Simple. They are too hard to pull. And they have a rubber 90 degree bend. So the rubber gets cracked right below the 90 because people tend to pull on the wire and bend the and crack the rubber. Which is where the wire terminal is. So you get an arc once the crack opens up enough and humidity or such sends the voltage a few volts higher.

When my originals final, I replaced them with originals under warranty. I remove the replacements with care (never bend that 90). Those have about 50,000 miles now.

If they reduced the pull, we wouldn't have issues. If they double insulated the terminal so it didn't arc if it cracked the rubber elbow, we wouldn't have issues.

In my case, I used a bit of "mechanical sympathy" and never pulled on the 90-deg bend ... I used a combination of pulling straight up and pushing from the bottom.   I never minded - "tight" is good for a spark plug boot when you're traveling in monsoon conditions and want the bike to keep running.

You're right, they should have designed for "Normal Use" and not built a weak point into the part that wasn't user-friendly ....

Jeep did that on the windshield wipers on my 1980 J10 pickup.   On almost every other car I know, you can pull the windshield wipers back off the windshield to clean it or scrape ice off of it.   On the Jeep, the normal pull that you would use to move the wipers back would snap the linkage right in two - they weren't made to pull back but your average service station guy didn't know that .... OR your normal owner.

Lannis

[Dilliw]

My Griso had the later version of those caps and had a ton insulation on them but the bike would run like crap at low rpm or in the rain.  For $20 and a hour's worth of work I'd say the  SB05E/SD05F mod is the beat bang for the buck in improvement you can make on an 8V.

Thanks again Leafman!

[Bulldog9]

Just had this done on my 8V Norge. It's all fun and games until you want to remove the plugs again and can't get a grip on the new plug cap and the wire pulls out. Yeah, thats going to be a good long term fix.  Time to buy a cache of plug wire...... Stuff like this pisses me off.

[Dilliw]

Just had this done on my 8V Norge. It's all fun and games until you want to remove the plugs again and can't get a grip on the new plug cap and the wire pulls out. Yeah, thats going to be a good long term fix.  Time to buy a cache of plug wire...... Stuff like this pisses me off.

Try starting it with a long screwdriver through the port hole.  Phang had a write up/photo of it:





Model: 1200 8V ENGINE.

Subject: Removing the spark plug boot correctly.

Dear Dealer,

We are writing to inform you of a practical and simple method for removing the spark plug boot on 1200 8V engines.

As shown in the photo, insert a normal flat headed screwdriver into the drain hole in the spark plug well on the head, on either the intake side or exhaust side. Apply leverage, pushing down on the screwdriver, to lift the boot.

This procedure significantly simplifies the removal of the spark plug boot and preventing damage to the boot itself, which is not reimbursable under warranty."

[Bulldog9]

A million thank yous.....

[leafman60]

The "correct way" of removing a plug boot is all well and fine.  However, please be aware that, on my bike, the boot failed and to my knowledge the boot had always been removed by the "correct way."

I am not sure that the "correct way" with the screwdriver is a guarantee that you won't have a boot failure. Even if it works, it's sorta stupid to me to have to baby it that much. The NGK hard caps allow something you can pull on without creating a problem.

By the way, the stock rubber boots were supposedly a USA-made product!

[Bonafide Bob]

I find the best way to remove the stock plug caps is to slide a zip tie under them and lift them up.
Bob

[Bulldog9]

You can get your fingers down the tube to pull up on the NGK cap? 

The "correct way" of removing a plug boot is all well and fine.  However, please be aware that, on my bike, the boot failed and to my knowledge the boot had always been removed by the "correct way."

I am not sure that the "correct way" with the screwdriver is a guarantee that you won't have a boot failure. Even if it works, it's sorta stupid to me to have to baby it that much. The NGK hard caps allow something you can pull on without creating a problem.

By the way, the stock rubber boots were supposedly a USA-made product!

[Pazzo Gatto]

Just stumbled on to this tread.  After 2 valve lash adjustments and a replacement of the OEM plugs with Iridium's, I've never pulled the plug boot from the valve cover.  Call me lazy, but I've just removed the 4 bolts and removed the cover, leaving the plug boot in place in the cover.  It never occurred to me that I should remove the plug boot.  Never had a problem (yet) and the plug boot just snaps back in place on the spark plug when replacing the valve cover.

[Lannis]

Just stumbled on to this tread.  After 2 valve lash adjustments and a replacement of the OEM plugs with Iridium's, I've never pulled the plug boot from the valve cover.  Call me lazy, but I've just removed the 4 bolts and removed the cover, leaving the plug boot in place in the cover.  It never occurred to me that I should remove the plug boot.  Never had a problem (yet) and the plug boot just snaps back in place on the spark plug when replacing the valve cover.

I would NEVER have thought of that, and I'll bet no one else has either.   That's a great solution that won't destroy the boot ...

One of those forehead-slapping things!

Lannis

[leafman60]

You can get your fingers down the tube to pull up on the NGK cap? 

Yes I can, but look at the original pictorial early in this thread. You can also make a zip-tie puller.

[Sashadeboer]

Thanks for all the pics Leafman60, that's awesome.

[bobrebos]

I ordered the NGK SB05E and the SD05F (to use the rubber boot off of and place on the SB05E) for my Alaska trip.  Il put them in the bags and hope my originals dont fail but better safe than sorry I guess.......Now to take those running lights apart to check for chafing wires...

[MotoG5]

Yes I can, but look at the original pictorial early in this thread. You can also make a zip-tie puller.

Have used the zip tie puller for six years now and still running original caps. I do carry a set of SB05E just in case.

[guzzisteve]

If you have the caps don't wait for a fail to put them on. It may not be a good time on the side of the road, it may also be raining.

[bobrebos]

If you have the caps don't wait for a fail to put them on. It may not be a good time on the side of the road, it may also be raining.

Do they fail from how they are taken on and off, or do they just fail while on the bike on their own??

[pete roper]

Do they fail from how they are taken on and off, or do they just fail while on the bike on their own??

Generally they fail due to abuse when being removed. People grab the tops of them and twist and tug at them, sometimes with pliers, and they get ripped. Small tears in the corner of the cap usually and the spark earths to ground through there to the rocker cover.

The best way to remove any plug cap on an 8V is to insert a long, thin screwdriver through the cooling tunnel just above the exhaust header. You can poke about until you feel the rubber of the cap or, on the case of NGK caps the sealing cap on the end of the bakelite plug caps themselves, hook the screwdriver blade under it and lever it up from the bottom. Very easy after you get the hang of it.

Also note if you are fitting NGK caps to a Stelvio you will almost certainly need to make up a slightly longer HT lead for the left hand side or it won't fit under the lead cover. An inch or so is all that is needed.

Pete

[Lannis]

Do they fail from how they are taken on and off, or do they just fail while on the bike on their own??

Enhanced from an earlier post in this thread:

Just to experiment, I bought a pair of SB05E and a pair of SD05F and put them in my fairing pocket, to see how far the originals would go.   Was the weakness of the originals an urban legend or not?   

The left side (the hardest one to replace because you have to shift a fairing piece to reroute the existing wire to gain the extra inch that Pete mentions above) went bad at the National in New Hampshire, right in the fairground, so we had a bit of tech session to replace it.  I had not had the boot off for 5,000 miles or so, rode about 600 miles to the rally, had started the bike for a ride-out, was idling through the fairground, and suddenly one side went dead.  33,000 miles on the bike.   I would not have wanted to replace it on the side of a muddy highway 4,000 miles from home.   

The right side went bad just as we started a 2500 trip with friends.   Took 5 minutes, 40,500 miles on the bike.    The bike went to one cylinder as it was running.

That amazes me, since the OEM boots LOOK and FEEL like they're the toughest, heaviest spark plug boots ever made.   Obviously, however, they are not - someone screwed up the design on these, one of the simplest and longest-used functions in automotive history, and it's Japan Incorporated to the rescue ....

Lannis

[bobrebos]

Enhanced from an earlier post in this thread:

Just to experiment, I bought a pair of SB05E and a pair of SD05F and put them in my fairing pocket, to see how far the originals would go.   Was the weakness of the originals an urban legend or not?   

The left side (the hardest one to replace because you have to shift a fairing piece to reroute the existing wire to gain the extra inch that Pete mentions above) went bad at the National in New Hampshire, right in the fairground, so we had a bit of tech session to replace it.  I had not had the boot off for 5,000 miles or so, rode about 600 miles to the rally, had started the bike for a ride-out, was idling through the fairground, and suddenly one side went dead.  33,000 miles on the bike.   I would not have wanted to replace it on the side of a muddy highway 4,000 miles from home.   

The right side went bad just as we started a 2500 trip with friends.   Took 5 minutes, 40,500 miles on the bike.    The bike went to one cylinder as it was running.

That amazes me, since the OEM boots LOOK and FEEL like they're the toughest, heaviest spark plug boots ever made.   Obviously, however, they are not - someone screwed up the design on these, one of the simplest and longest-used functions in automotive history, and it's Japan Incorporated to the rescue ....

Lannis

Thank You.  I will replace mine before they fail on their own, and before my Alaska trip.   

[JeffOlson]

On my first Norge, one of the spark plug caps/boots went bad after taking the bike to the dealer for its initial service. On my second Norge, I had the dealer (a different one!) replace the caps/boots before I rode the Norge off the lot. Preventative maintenance...

[bobrebos]

Well, the NGK plug caps are now on order, so Il be cutting off the stock ones soon.  Seems a shame to do this but if they all go bad like everyone says, I guess I better before Im stranded on the roadside.......

[JeffOlson]

^ Yep.

[bobrebos]

NGK Caps arrived today and I cut the old/stock ones out and put the new NGK in.  Hope they dont give me any problems but those Guzzi ones seemed built pretty well????  Well...time (and miles) will tell. 

[Dilliw]

If you have the caps don't wait for a fail to put them on. It may not be a good time on the side of the road, it may also be raining.

Yeh I've never understood this thinking.  The NGK combo is a $20 + 1 hour solution that should last for the life of the bike. It's not a wear item like a tire or a battery, and they will affect performance long before they actually fail.   

I guess there is some challenge in babying the OEM plugs so that they will last but to me it's just one less thing to worry about.

Fix it and forget it.

[Lannis]

Yeh I've never understood this thinking.  The NGK combo is a $20 + 1 hour solution that should last for the life of the bike. It's not a wear item like a tire or a battery, and they will affect performance long before they actually fail.   

I guess there is some challenge in babying the OEM plugs so that they will last but to me it's just one less thing to worry about.

Fix it and forget it.

I carried my new ones, but it was an experiment, like leaving the stock mirrors on.

We KNOW they're going to fail, and people's plug wires and mirrors were failing in 4K to 20K miles, but let's see how far they WILL go.   Maybe I can set some sort of record, or maybe mine WON'T fail.

So I found out - the mirrors failed within 1000 miles of each other, and the spark plug boots failed right on schedule.   

The only thing I DIDN'T do that with was the flat tappets, for sort of obvious reasons involving huge piles of money, but until I hear different from another 8-valve owner, I'm claiming precedence with 40,000 miles on the original tappets and changed them out RIGHT before they failed - discolored but had not lost any material yet.    The shop estimated I had another 500 or 1000 miles before bits would be in the bearings ....

Living dangerously!   

Lannis