Even with a good crank a engine like the V twin for normal street use needs something to dampen the power pulse in the lower RPM. Many guys have tried the solid comp route and most do not like the jerky-ness in low RPM and many time it will transmit vibration as well..
Now on inline smooth imports sure but not so much for a 900+ lb bagger chugging around in a parking lot.
I suppose.. just thinking, though. Maybe its the 900lbs or the length of the stroke.... Like you, I have had more than a few Vrods apart and they are gear driven on that side, with no comp, except for the floating rear belt sprocket (like our 09 and up touring). With those, they are smooth above 2K rpms. Am I comparing oranges and orangutans?
I do think the next time I go into the primary I will swap to a stronger clutch and a solid sprocket. I need to get the trap door replaced this winter so that might be the best time... I'll save the comp and worst case, its a gasket and couple $$ paper weight.
Chris