Yeah some of the Suntour stuff was well made, especially Superbe & Cyclone. Their index shifting just never worked as well as Shimano.
That's exactly what I was talking about. It's essential for index shifting to work well. By comparison, the Suntour cassettes that I saw in the shop back then had simple consistent tooth profiles. None of the tooth shaping, angling, ramping, etc. that Shimano used. Like this:
View attachment 81185
As I was pulling my hair out trying to get Suntour index shifting to work as well as Shimano, I realized the cassette tooth profiles were part of the problem. All that funky stuff Shimano did to the cassette teeth made the chain shift more readily.
I'm at home now and had a quick look at my old bikes. I don't ride them, but I just can seem to get rid of them where they just take up space in my storage room. But yeah the teeth are twisted at different angles, some teeth are thinner, some are angled weirdly,, and parts of the base are shaved off. I see this even on my 7-speed Dura-Ace freewheel. I don't recall if I had that on my old 6-speed Peugeot with a Maillard freewheel. They might have just used a Shimano shifter with a traditional tooth freewheel. That bike was trashed and I'd already swapped out some components before I crashed it. It still shifted pretty well. But I found a photo of one, although it might not have all original components. The saddle is definitely not original. I forgot who made the tubing, but it was French. I looked it up and it's something called "HLE".
As far as Suntour goes - they never made a complete groupset like Shimano or Campagnolo. I think they contracted with Sugino to make the crankset and chainrings, although Suntour made the bottom bracket. I thought that at least some of the Suntour brakes were made by Dia-Compe. And of course Campagnolo made rims. They had some weird stuff too like the corkscrew. I saw a few bike shops that had it - almost as a gag although I'm sure they would sell it.
I'm trying to figure out what was the Schwinn that was looking for in college. Might have been their 754. The list price was about $750 and I found it had Suntour GPX components. There was another bike I was considering at the time - a Bianchi in their signature light green color with Suntour GPX. But it was actually a Japanese bike probably "rebadged" with Ishiwata steel tubing.