[BurbankScout]

Rolling down the rode today and hear the bike backfire then sound like I lost compression in one cylinder and then the bike died. Got pulled over to the side of the road safely and contacted AAA for a tow to my local Indian dealer. While waiting for the tow truck a couple friends and I fired up the bike. It displayed the same symptoms plus I could smell gas. I checked the rear cylinder spark plug and found it had blown out of the cylinder head!

Quick trip to the nearest auto parts store for two new plugs (gapped to .040"), replaced the rear plug, and she fired right up and we made it home. Once home I replaced the front spark plug as well and also found the front plug was less than finger tight.

Lesson learned - check your plugs every now and then.

 

[Ridgeracer]

Crazy story Burbank. Were the threads stripped at all? That would be a concern, as well as was there anything sucked in the head after the plug flew out. Likely not given you pulled over immediately it sounds like.

 

[tribaltek]

Scary situation! Also interested in hearing about the threads. Did the new plug seat in ok?

 

[Black2016RMrider]

Good reminder - I’ve checked mine and found them loose

 

[OracleDba]

My experience is one could/should confirm torque after one or two thermal cycles but thereafter they are fine until plugs are due to be changed again.

 

[BurbankScout]

The threads were not damaged and the new plugs seated just fine. I'll give the new plugs a check this week. I rode yesterday without any issues.

 

[Davetac1]

If the plugs were installed [torqued] correctly to begin with,then none of this would have happened.Hence the blame for this little mishap would be on the person who changed em.If it was a stealership,then shame on them.If it was you,then shame on you.And all this is the reason "WHY" I do all my own work which isn't all that diffucult to do because this is what I have done all my life to earn my living!!

 

[OracleDba]

please ignore this edited mis-post

 

[Charlie Chaplain]

If the plugs were installed [torqued] correctly to begin with,then none of this would have happened.Hence the blame for this little mishap would be on the person who changed em.If it was a stealership,then shame on them.If it was you,then shame on you.And all this is the reason "WHY" I do all my own work which isn't all that diffucult to do because this is what I have done all my life to earn my living!!

I agree, Dave. There is a crush washer on every spark plug, and after it is correctly tightened, it will NOT back out. You don’t have to be Magilla Gorilla on the ratchet, but proper tightening of the plug will give you security in knowing this won’t happen. I like to put a little thread lube on my plugs. This gives it a chance to be removed without stripping threads from dissimilar metal reaction too.
Charlie

 

[Davetac1]

Ya always wanna use alittle copper anti seize on the plugs' threads because the heads are aluminum.And then it's also a good idea to use the correct torque spec from the SM so ya don't over torque em.What ya don't wanna do is strip the threads in the heads,or break the plug off cause then you'll really have a problem.Don't ask how I know this. After close to 70 years in this business,ya gotta learn something!! Well,,, most guys do,just not dummies like me.DUH!!! Dave!!!