Sounds like the clutch... as others have mentioned, try adjusting it first...

IMHO, take off the outer primary and inspect it 2nd, then based on the inspection, maybe replace it is third...

Another thought just popped into my head... from when you say "jumping" when trying to accelerate at speed.....

"Basically, If I’m traveling at highway speeds and try to accelerate too quickly, I can feel what i assume is the transmission almost jumping. Some described it as slippage, but it doesn’t quite feel like slipping in a way I’m used to"


Based on your description and gut feeling, make sure to inspect your final drive belt..

My guess would still be the clutch, but inspecting the drive belt and sprockets is the cheapest and easiest thing to do..

If the drive belt is the cause, and it has damage, is too loose, the drive belt sprockets are worn/damaged, and/or any combination of these... it is possible your drive belt could be jumping a tooth on one of the sprockets when you hit the power at speed..... If this is the cause, it should be pretty obvious from a good inspection of the drive belt and sprockets...

Good luck with your repair and keep us posted....

 

Not disagreeing with the other guys in any manner, they are 1000x more knowledgeable on HD's than me. But one simple thing - Have you inspected the belt? Any excess rubber dust or missing teeth, loose?