[B0B]

Hi all,
I decided to replace all 4 sparks on my r ninet (9k miles). Possibly early doors though keen to see the state of the plugs not having owned the bike from new.
All looking good until removing the right, secondary ignition plug.
It was black and wet. Looking at the ignition coil it didn’t seem to quite ‘click’ into place when putting back on.
Could it be the coil is faulty, not generating a spark? The primary spark was in good health.
Any thoughts/suggestions?

 

[UGS_Tom]

Some more informations could be helpful.
Does the bike run normal?
Had the sparks been changed at the last service and the coils properly refitted?
Any cable damage?
Have the plugs beeing well warmed up before you checked?
Same specs for all 4?

This can happen especially at the left side because of the side stand. (Due to the installation position - they are at the bottom of the combustion chamber- they are wetted by small amounts of remaining oil. The left side in particular is predestined for this.)
... clean it, dry it (hairdryer), put back again (or try a new one) and be sure the coil fits tight.

 

[B0B]

Some more informations could be helpful.
Does the bike run normal?
Had the sparks been changed at the last service and the coils properly refitted?
Any cable damage?
Have the plugs beeing well warmed up before you checked?
Same specs for all 4?

This can happen especially at the left side because of the side stand. (Due to the installation position - they are at the bottom of the combustion chamber- they are wetted by small amounts of remaining oil. The left side in particular is predestined for this.)
... clean it, dry it (hairdryer), put back again (or try a new one) and be sure the coil fits tight.

Thanks Thomas,

the bike runs well. No issues there.
Unsure when plugs were last changed. Not noted in the service book and only done 9k miles.
Theres no damage to the coils, just when putting the right side secondary on it doesn’t seem to click in very well.
I was more wondering if that meant no spark on the plug. Or even with a poor fitting coil would it still spark.
All other plugs looked good at the same time when changing them.

 

[arfingdog]

If your bike only has 9k miles on it, the plugs probably hadn't been done before, as I think the standard service interval on plugs is 12k miles.

 

[B0B]

Yeah, that’s what I thought. I just wanted to know the state of everything so changed all oils and plugs.
Odd that this one secondary plug was black and wet. Made me think the spark to it was poor - especially with the coil not really clicking in when refitting.
Surely an engine warning message would pop up if it wasn’t sparking though?

 

[dxamet]

Each cylinder has 2 spark plugs, it is quite possible that one spark plug will not cooperate without the driver noticing.
With the 1150 twinspark engine many stick coils failed. The engine continued to run, only minor hiccups at high revs and backfire were the symptoms.

 

[vagueout]

I have three boxers all with stick coils. Whenever I lift a stick coil off, I spray in and around it with a shot of contact cleaner, shake dry and then a shot of silicone spray inside and outside of the stick coil, shake out for a few seconds and then push back into place. The contact spray is self explanatory, for cleaning, the silicone shot helps ward off corrosion, I live next to a beach, and also ensures the coil properly clicks onto the spark plug.

 

[Patrolus]

From my experience the 2ndary plugs always look a bit worse.. As you say everything runs smooth - I wouldn't worry about it...

 

[B0B]

Thanks for all the feedback. I had thought I could disconnect the coil (leaving the plug in), then connect to an old plug, run the engine and confirm it sparks.
Worth going through that?

 

[Crankpin]

Thanks for all the feedback. I had thought I could disconnect the coil (leaving the plug in), then connect to an old plug, run the engine and confirm it sparks.
Worth going through that?

That's exactly what I'd be doing.