spark plug

[Hugo a Gogo]

What's happened here? Or have I just dropped it right on its end after I took it out? 😅 I must admit I only gave it a cursory glance before putting it on the floor. It couldn't have run like that, surely?

[Derry Rhumba]

fk me!

What are you going to measure the "gap" on that with, a pry bar?

Seriously, that couldn't have run normally with that in, surely.

[stevieturbo]

What on earth is it for ?

The whole top body looks mushroomed too, threads not exactly nice ?

Clearly that will not be able to produce a worthwhile spark, so what was it removed from, and was it running at all ?

[Hugo a Gogo]

It was in my bike, a Cagiva Raptor 650, which is the Suzuki SV650 engine. It started running really rough, on one cylinder ( V twin) and the Suzuki has a kinda reputation for losing the front cylinder due to water getting in the the plug hole area, so I thought it was that, bought some plugs, changed the front one, and it was still running on only one, so lifted the tank to change the rear one, and the plug cable was hanging loose! Swapped the plug anyway while I was in there, and that's what was in. It surely landed right on the electrode bit when I dropped it onto the ground
Anyway, it runs fine now, not that I ve been out on it, just started it up
/Too much back story

[E-bmw]

That looks like the end has been well & truly hammerred all the way round, ven the end of the thread looks like it is "mushroomed".

Pic of new one for comparison would be helpful.

[Hugo a Gogo]

I didn't take a pic, but it's a cr8eix iridium thing in there now, the old one just a cr8e

[Hugo a Gogo]

Could the piston be somehow hitting it? If bearings are really loose or something???

[Hugo a Gogo]

Or if the plug lead was off, and I rode it a couple of miles home on one cylinder, the compression or detonation or something closing the gap?

[stevieturbo]

Hugo a Gogo said:

Or if the plug lead was off, and I rode it a couple of miles home on one cylinder, the compression or detonation or something closing the gap?

I've seen detonation close gaps yes.

But if the lead is off and it isn't sparking at all, not an awful lot will be happening in the chamber,

But the mushrooming looks like physical damage and lots of it. Very strange. Although also fairly smooth looking. Surprised it didn't damage threads on the way out ?

[Tuktuk]

I'd want to be getting a bore scope into that cylinder and checking the top of the piston for matching damage.