Bicycle Mechanics - Freewheel cog spacing?

I have a 1988 Club Fuji with Suntour Accushift SIS/Friction so my question is will any freewheel with 5mm spaced cogs work in SIS mode? The current and original FW is a Suntour Ole' 6 speed 13-24 and spaced 5mm. I have a Suntour Winner Pro and wonder if it will work and also a Shimano 600 all 5mm spaced?

Just to clarify, "SIS" stands for "Shimano Indexing System", so you don't have SIS Suntour shifters.

I would expect any freewheel with the correct spacing to index fine. I've had good luck mixing and matching Shimano 7-speed spacing with 8-speed shifters and vice versa (which are slightly different, I can't remember the numbers.) It's not an absolute exact thing.

Friction shifters work great. that way,

You can make any of those work if you use a bit of finesse .. :fred:

I have a 1988 Club Fuji with Suntour Accushift SIS/Friction so my question is will any freewheel with 5mm spaced cogs work in SIS mode? The current and original FW is a Suntour Ole' 6 speed 13-24 and spaced 5mm. I have a Suntour Winner Pro and wonder if it will work and also a Shimano 600 all 5mm spaced?

Probably not. Suntour and Shimano differed in that Shimano's cogs were spaced evenly from bottom to top. Suntour's were not. You might be able to switch to the Winner Pro freewheel without issues, but I'd guess that the Shimano freewheel will have issues.

I have a 1988 Club Fuji with Suntour Accushift SIS/Friction so my question is will any freewheel with 5mm spaced cogs work in SIS mode? The current and original FW is a Suntour Ole' 6 speed 13-24 and spaced 5mm. I have a Suntour Winner Pro and wonder if it will work and also a Shimano 600 all 5mm spaced?

Out of all the freewheels you've listed, you'll find that the Shimano one will work the best. Most likely it's a Uniglide freewheel with the twist-tooth which works better than the thick blunt ends of the Suntour cogs.

Just to clarify, "SIS" stands for "Shimano Indexing System", so you don't have SIS Suntour shifters.

I know, I wasn't thinking when I typed that:(

I've measured all 3 freewheels and they all have the same spacing hight to low, so will all work?

I just switched the dial over to the friction mode so I suppose any freewheel would work, correct?

Friction shifters work great. :fred:

Good index systems work better.

Good index systems work better.the Good ones .... Rohloff

NB: the dozens of pages where people cannot make their front click,
and the rear mech talk to each other and want help.

I know, I wasn't thinking when I typed that:(

I've measured all 3 freewheels and they all have the same spacing hight to low, so will all work?

I just switched the dial over to the friction mode so I suppose any freewheel would work, correct?

As Danno pointed out, the Shimano twist-tooth cogs shift far better than the Suntour flat-top cogs. As long as you've got all the freewheels, try 'em out and find out for yerself!

Good index systems work better.
+1. The fact that some riders don't tune them properly doesn't mean the systems can't and won't work extremely well if set up correctly and it isn't that difficult.

I just switched the dial over to the friction mode so I suppose any freewheel would work, correct? Absolutely.

Indexing performance can vary greatly depending on the level of modern-ness of the sprocket teeth and chain.

For spin-on freewheels, 5-speed Shimano UG models work best. For 6 or 7 speeds, Shimano offers HG freewheels. I have used chains as narrow as Shimano 9-speed on Shimano 5-speed freewheels, index or friction shifting was great. The 9-speed chain might not play nice with older 5/6 speed spacing on the chainwheels, sometimes it's good but some particular cranksets from the old days like a bit wider chain. The 9-speed chains also worked particularly well with Suntour's Ultra-6 and standard 6-speed freewheels, but not with old French or Italian freewheels.