Shimano Seven Speed Cassette Differences..?
 

My recent project, refurbishing a Marinoni Special that I bought last summer, has presented me with a learning opportunity. Frankly, I know little about the Shimano seven speed cassette. Though my memory might be playing tricks on me (again), it seems to me that there were two different Shimano seven speed cassettes. My Marinoni is fitted with this cassette...
https://cimg2.ibsrv.net/gimg/bikefor...3e5afd6e64.jpg

Sadly, for me, the rims on the bike, "as found", did not match (rear 36 and front 32 spoke holes and different makes). They were close and are being used (temporarily) in the build. I have a nice set of Mavic 32 hole rims (could be NOS) and decided to buy a set of Shimano seven speed hubs with a matching hole count. Sadly, again, my Marinoni cassette did/does not fit the purchased hub set.

My question is is there two seven speed models? Which one do I need? Once I know, I will try to find a proper cassette and one with a big cog that exceeds 23 teeth (26 would be much better for this old fella)...
https://cimg7.ibsrv.net/gimg/bikefor...419ecb7fbf.jpg

In your pic is a modern hyperglide hub which is the current standard.
You may have bought a uniglide hub which is archaic and defunct.
https://www.sheldonbrown.com/k7.html#uniglide

Sheldon's suggestion was to transplant a hyperglide freehub on to there which is pretty straightforward.

I know there are cassette purists, but your 105 set is workmanlike and doesn't really need a fuss over period correct consumables. There are 2 off the self currently available decent silver 7 speed cassettes, the 11-28 shimano acera one, and the 12-32 sram one. Both about $20. I prefer the Sram.
Wider gears is always better. You would almost certainly shift the 11-28 and might do the 12-32 with a flipped b-screw, if not, a different derailer. The 11-28 can be improved by swapping a 12t top cog, so you get 12-13 (and a silver lockring).

Dunno about the HG 7sp cassettes, but there were a couple different threaded freewheels offered. One appeared much like the photo you posted, but the one I wound up using had a 34-tooth granny gear for touring, instead of a 28-tooth low gear. There was a pretty fair jump from the 34t cog to the one below it, but it seems to shift okay. It wouldn't surprise me to learn that there's similar HG cassettes available.

Depending on which freehub you have, it may or may not work with the 11T small cog. If the splines go all the way to the end it won't take a 11T . If the splines stop short before reaching the end, then it will take the 11T.

Shimano offered quite a few combinations of 7-speed Hyperglide cassettes back in the day (actually, until somewhat recently.) Sheldon Brown kept a chart on his site: https://www.sheldonbrown.com/k7-7.shtml#shimano7

I used a 13-28T "M" cassette with that exact 105 RD with no issues whatsoever.

Shimano 7- and 8-speed cassettes are typically bolted together, or rivets that easily be drilled out on the head end. The loose cogs and spacers can then be grouped in whatever combination suits your legs and terrain. SRAM cassettes can also be disassembled into loose cogs and Miche cogs also work fine.

No, the bolts and rivets don’t add strength.
No, the grouped cog sets do not have to be matched. I’ve only noticed less than perfect shifting (sometimes) only when the cogs are a single tooth spaced.

The 8-speed cassette on my Marinoni is 12-14-15-16-18-21-25-30, assembled from a mix of cog brands - Not a combination in any catalog!

I'm with Dfrost on this. That is likely a 11 /23 or 12/23. The simplest thing to do is drop the smallest sprocket and add a 26 to the other side of the cassette.
That is assuming you don't need the smallest sprocket.
And you have the tools or a shop willing to do it for you and access to a spare sprocket.
And it is possible to clock the cog yourself by filing of the long tab on it and rotating it to the correct position. It only needs to be clocked to the adjacent one.
And you may not even have to adjust the cable tension or limit screws for it to work.
Obviously you have to check that's true.
And it is difficult to find a new cassette that actually suits your needs rather than the population as a whole.
Pardon me, i just realised who the o.p. is. He will be able to figure it out.

My money is on [MENTION=84826]randyjawa[/MENTION] having a 13-23T "I" cassette on that wheel. ;)

Well, the Marinoni is coming along. The 32 hole Shimano 600 hub set I bought is the wrong one. This set does not have the one wider spaced spline...
https://cimg7.ibsrv.net/gimg/bikefor...e6e2af5a91.jpg
https://cimg8.ibsrv.net/gimg/bikefor...2c1eda648b.jpg

None the less, even though the wheel rims do not match, they are close enough for now. With that in mind, the original hubs and seven speed cassette will do just fine...
https://cimg2.ibsrv.net/gimg/bikefor...efc5bc09c1.jpg
https://cimg3.ibsrv.net/gimg/bikefor...4e471028d7.jpg

Install a chain, tune the bike up and, after double checking everything to ensure that I did not forget something, time for a test ride. Once satisfied with Brifter location, time to install the inexpensive handlebar tape, that arrived from China about an hour ago. Looking good and looking forward to the next phase in the build...
https://cimg7.ibsrv.net/gimg/bikefor...ef52a91f9a.jpg

If you did want to use those hubs it's pretty easy to get a hg cassette on there.

-ish. Grinding down the wide spline and using the threaded sprocket is easy enough. However, I’d be concerned that the threaded sprocket is worn while the other sprockets were not. The only way to find out it to try it.

Lockring instead of the threaded sprocket if it is worn. Bsa bb lockring fits.
You do lose a sprocket but you really don't lose that much if the ratios you choose suit your riding needs.
It's just a suggestion to show that it can be done quite successfully if required.

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In this case I believe you have FH-6400, the one that is 7 speed and compatible with both UG and HG is FH-6401.

Been at the Marinoni again and getting close to finished. Lots of Marinoni interruptions due to a refurbishment of the back entrance room of the lake cottage). Anyway, let me see if I understand...

I can file or grind the one wide tab on my seven speed cassette so that it will fit my 32 hole hub. That sounds good. I will take a closer look to see what it all looks like in the real world. I would really like to use the 32 hole rims, as they appear to be NOS Mavic hoops with machined brake surfaces (I loathe anodized brake surfaces, particularly dark anodized ones). Why? Because, in short order, they end up looking like this...


https://cimg2.ibsrv.net/gimg/bikefor...6aee230c19.jpg

And, it really bugs me to have mismatched wheels on one of my bikes. More so this one since it will, most likely prove to be a keeper. Spent some time on the bike today. Gotta go to the city tomorrow to get a chain, some spare links, handle bar tape (actually, some arrived in the mail the other day - four sets, $12.00 delivered) and some more lumber for my refurbish the rear entrance way project...
https://cimg3.ibsrv.net/gimg/bikefor...34b81e0a5a.jpg