This last friction combo I tried that fails me, its a modern sunrace 8 spd cassette with an all original 6 spd bike. I'll try lube and adjusting it up, but I think based on the feedback in this thread it it may just be me.
The thought crossed my mind to grab one of the ubiquitous 7spd mtb cassettes and chop off the low gear... I may try that in index mode just for kicks. I ordered a pack of spacers to get 7's onto the wider freehubs, should come in any day.