Hi, I am replacing the head bearings on my 86 K100, it had a RT fairing on it , I have removed that and pulled away the speedometer ect.
At some point this part fell off and I found it on the floor. Any ideas?
The hole is threaded

 

 

Never seen that one....

I assume it’s metal?
What is the span across the flats?

I'll guess non original replacement. What's the internal diameter? Maybe it matches the vacuum caps, if ones missing. Or replacing the rubber supports for the tool box, or fuse box, especially if one's missing and this substitutes it.

Muffler bearing cap.

Metal, rubber or plastic?

What size are the threads?

Can you take a picture with a ruler in it?

Thanks for the reply's, the part is about 7/8 inch long with the flats about 1/2 inch and the threads the same as the transmission to bell housing bolts m8x45. I did take a look at parts fiche with no luck . The material seems to be a nylon type deal.
I have never seen it in my shop before, possible some one is messing with me. On the plus side I figured out how to post photos from my phone.

Some kind of steering stop ? Maybe ? 
regards
Bill