What is this upper tree hollow nut for?

[lemonshindig]

I royally screwed up the triple tree for my 78 GS1000. I have another set that I bought, but the steering stem is about 3/4" longer and has a hollow hex nut instead of a bolt. What is this used for? Wondering if I can do this swap.

This is the style of my original stem:

[lemonshindig]

But my replacement is this style:

[Steve]

Not sure when the chain-driven E models changed from having a lever on the carbs,
but the '80/'81 850 and 1000 shafties had the "choke" knob there.

.

[hillsy]

Your replacement clamps look like leading axle clamps. The offset of the forks v stem is different between the two types.

If your original forks are not leading axle, then the new clamps will change the geometry (possibly dangerously).

[Guest]

Definitely check to see if the fork clamps and steering stems line up to make sure, but the hollow stem shouldn't make any difference if everything else is the same.

BTW, the 79 850G I have has the choke down the center stem.

[lemonshindig]

Thanks guys! My trees are exactly the same. Only the steering stem is different. I took these pictures off of ebay- they are not my parts.

Choke knob. 10-4. Thanks!

[TxGSrider]

I believe the ones from the GSX-R front tree that I used was hollow (weight savings?) but there was a big chrome nut that went over it.

[wymple]

Definitely check to see if the fork clamps and steering stems line up to make sure, but the hollow stem shouldn't make any difference if everything else is the same.

BTW, the 79 850G I have has the choke down the center stem.

So does my 81 850G