Does anybody make a spring, or linkage for this?
Maybe I'm a sissy, but I can't get used to the standard wire throttle that does not return.
Aggravated by my 2010 Dyna that does return

 

Two ways it has been done

yes they make a bracket and a spring fo the carb end - new design

50 years ago they would take the end screw and attach a spring to it between it and the riding sleeve in the handlebar to pull the cable. - only have a simple drawing of the workings

 

Hard to explain, but you can put a spring in the handle bar between the plunger and the cable ferule. Doesn't give you 100% return, only about 85% but will give you want you are looking for.

I have also seen lots of springs just hooked on the the lever on the carb going back to the frame or the heads. Very caveman, but it can work. Sometimes you will see a hole drilled in a fin for the spring to hook into.

For me, I just removed the spring in the handle bar before my cross country trip because I wanted the cruise control to work. I am good without a spring, just need to get used to it.

 

I've stared at the carb looking for a non-caveman solution
Saw and bought this solution - supposedly works on a 45.
It appears to replace the existing throttle shaft with a longer one.
I'm a little worried as I replaced my old shaft and the bushing was honed to fit the shaft.
I could be going backwards

 

Yeh, don't mess with that shaft unless you must. It will cause a leak for sure.

Just hook a spring from the lever on the carb to something, see if it does want you want. You can get all sexy later if you like the functionality.