Thanks one and all for the very helpful responses!
My fuel line situation is in good working order.
I’ll look in to a dellorto square pump.
Thanks for the specific make/model of carb recommendation for the CR 80. I am currently running the stock Keihin carb.
I’m betting it has a lot to do with jetting; the motor felt like it was signing off halfway through the powerband in some turns and straights; and a plug test showed it was on the rich side. ( motor has excellent compression )
I wanted to swap to a flatslide carb due to my experience with them in MX and sleds. I’ll keep adjusting the jetting and hunt for the Mikuni model.
I especially appreciate the jetting suggestions. I realize they vary based on many conditions, but a starting point is very helpful. All comments and suggestions welcome.