Spark Plug sleeves?

[bikmakr]

I pulled my plugs off my 712 and all of them had copper sleeves around the threads. Are these stock? Should they have remained in the heads? Did someone repair the threads? The plugs were number W7DC. Help !!

Thanks

[Haf-e]

That doesn't sound good - shouldn't be any kind of sleeves that come out with the plugs. Can you post a picture?

All of the thread inserts I know of are suppose to stay in the engine after being installed... When properly done they work well.

[edzz]

any chance you are seeing copper colored anti-seize on the plug threads?