Wrong spark plugs and possible broken piston rings?

Help a newbee. I was riding one day and my bike started dragging. I pulled off and killed my bike. Upon inspection the airbox dumped a large amount of oil. I rode home in first gear. I pulled the spark plugs and found that the electrode at #3 was completely burned off. I examined the friction and plain plates on the clutch and found no problem there. I also examined the oil separator and found no sludge there. This is my first bike. When I bought this bike last June I replaced the spark plugs with the ones that were in the bike, Autolite 64's. I plan to replace these with NGK spark plugs. Did I unknowingly screw up? Do I have broken piston rings?


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rocs82650
It has 19k miles, it had 17k when I bought it.

I've been using the manual and following this website to learn about and work on my bike. So far I've:

Rebuilt both control switches. Stripped and re-soldered contact button to re-enable starting bike at the button.
New solenoid
re-wired new fuse box
made front flashers running lights
new tires
rebuilt mc and brake caliper. They were disabled when I bought it.
complete front forks removal, cleaning and repair
new brake pads on front and rear
new oil and air filter
new seat cushion and cover
new battery
replaced bent '82 handlebars with '81 bars.
about to replace modified stock exhaust that came with bike with Mac 4-2 complete + carbs jetting.

 

Probably not,
Do a compression test on the engine and let us know the numbers.
Seriously look at checking the valve clearences sometime soon.
Get the right plugs and try again after the compression test.
Can't say why you have oil in the airbox, could be worn rings but we need to start with the compression numbers.
Take some pics of the plugs and show us. Hopefully they are not black and oily. Light tan is good, white is lean.

 

Will do. Thanks Wiz.

 

Smell your oil. I'll bet you've developed a float valve issue and your crankcase is "overfilling" because of the added gas and pumping oil out the breather. Unless you just changed the oil and overfilled it. You're making quite a huge leap from oil in the airbox to broken piston rings (which you probably don't have.)

Buy some some NGK plugs. And check those valve clearances! I don't see it on your list.

 

Will do. Thanks Fitz.