I have a 2009 FLHR with about 6k racked up on the odometer.
Dropping the bike into 1st gear results in a rather loud "clunk" and a bit of a detectable lurch forward.
I've never had any creep at a stop or any reason to believe the clutch is dragging.
The dealer filled the primary with the prescribed (all synthetics) HD fluids at 1k, and I changed out the tranny fluid with Amsoil Severe Gear at about 2k to try and quiet the 5th gear whine.
I just recently adjusted the cable to the service manual spec of about 1/8" free play, lubed it up, and it seems to have helped slightly, but only after the bike is fully heated up.
I've tried to get in the habit of starting the bike with it in 1st gear to avoid that bang. It does tend to creep while the starter is turning the motor over, even though I've got the clutch nailed to the grip.
Is anybody else having this symptom?

 

What you are hearing is the dog engaging into the first gear cluster. The transmission is constant mesh. This means the gear clusters are constantly engaged. Dogs slide between clusters on the shafts to apply torque to the respective gear. You can see them in the photo. Just above #7.

Different fluids can change the sound. I would be upset if mine didn't do it.

 

Do a complete clutch adjustment with the bike completely cold and see if that helps. Many times the lurch is from cold primary oil drag until the oil warms up a bit. Some guys use a thinner primary oil than the 20w50 or formula+ which is a 50w. I use redline MTL which is a synthetic 70w80 manual transmission lubricant that pours like a 5w30 oil when cold and it reduces that a bit. But adjust the clutch first.

 

Very bad idea to start bike in gear, especially when clutch is dragging like that. Great way to have any number of failures in the near future.
Idle speed being high certainly contributes to this dynamic, as does a poorly adjusted clutch.

 

Well, I did a full adjustment on the clutch yesterday, and while it did not seem to improve my original concern over the loud clunk/lurch much, it did considerably quiet my at speed shifting. I'll be swapping out the primary and tranny oils today, time permitting, and probably tweak my clutch adjustment just a hair since it seems to be engaging a little early in the travel of the clutch lever.

 

Try some Redline MTL in the primary.

I've tried so very many different lubes in there, The MTL was the one that I stuck with because it shifted the smoothest.

Primary chain adjustment has a lot to do with it as well, but we are screwed on the newer bikes with the "not so perfect" auto adjuster.
At least with the old manual adjusters you could dial it in perfect.

 

I got the primary fluid changed out, but left the tranny fluid as is for the sake of the process of elimination. I put Amsoil 20w50 MCV in the primary. 2 votes here, and many postings outside of this thread will have me looking for the Redline MTL dealer in my area.

You know I must have read section 5 of the service manual about 6 times, and as close as they ever come to stating that the primary chain tensioner is automatic is this: "NOTE- Primary chain tensioner will not complete chain adjustment until vehicle is ridden. Vehicle must be test ridden after tensioner removal/installation to verify proper adjustment." Thanks for the point Faast Ed.
I didn't like the looks of the debris on the magnetic drain plug, or the dark residue on the inside of the clutch cover, so I'll be checking back in on this area soon.

 

Having debris on that drain plug is common. No need to worry unless you get a bunch of it. The oil gets dirty too. The clutch disks wear.