What is bracket #21 ?

[Bone]

See item number 21 just to the right of the fan blades ? What is it ?
The other day I found a piece of broken stud (the one from the very
bottom of the bracket) with a nut still attached on the garage floor. 
The nut was loose I unscrewed it with my fingers.
There is a rubber bushing #12 & #26 on the remaining stud.  I screwed
the nut back on and tightened.
The lower end of the bracket (#12 & #26 area) is not attached to anything.

[fordmano]

The bottom mount of the radiator, they look like a threaded stud I think. The ones on my I/S look threaded but don't stick through the rubber grommets, they dont stick far enough out to get any nut on them. The radiator pivots or tilts forward on them when you remove the single top bolt that attaches top Brandt of teh radiator to the frame.

And that my opinion and I am sticking to it!!!

[Bone]

Ok that makes sense. Grommet is the word I couldn't find when I said bushing. I see there are 2 brackets now I didn't look for another. The broken piece of stud is almost an inch long with more on the bracket that I screwed the nut on.
I will go out and look again to see what happened and what is left. I've been riding the radiator is secure.

[John Schmidt]

When you remove the radiator, after removing that top bolt you then slide the radiator to the right as you're facing the front of the bike(left when sitting on it). It slides on those two studs you're referring to, you don't use a nut on the outside to hold it in place.

[Bone]

Guess it's obvious I've never had the radiator off. Rolled the bike out into the sunshine and can see the tab from the bottom of the radiator thats on the stud. There was a nut on the stud that broke but I can see it wouldn't be needed.