Michael, and all...
This is not a Jihad... just my experience.
The HD thumbscrews I have were purchased from an outfit in Arizona called Direct Parts. Their p/n for them is CP005.
They fit HD Keihin carbs CVK40 and SE CVK44.
When I bought and installed them, I never looked at them closely, I just wound them in and backed them out 3 1/2 turns. The bike started better and ran fine. My springs, o-rings, and washers are intact, btw. Recently, a method of adjusting them by disconnecting a plug wire was discussed on here. I tried that and found that the HD screws made no difference until nearly bottomed out, and even that difference was negligible. The bike was still starting and running well, so I left them adjusted at 1 1/2 turns.
Recently, I had the opportunity to have a set made, based on my stock screws. I just got them at work tonight, so I haven't tried them yet, other than to make sure they screw into the carb correctly.
Top left is the new screw. Bottom left is the stock screw. The right is the HD screw.
I could not get any closer with my camera and stay in focus, but I think you can see the difference in the taper. The tapered portion on the HD screw is also very slightly longer as well.
And that's where I'm at with the thumbscrews right now.
Once I try them, I'll report back.
I don't know how the screws that Michael or Brent sells compare to our stock screws, I just assumed (yeah I know about assuming) that the HD thumbscrews were a specially made item and therefore all the same.
