phtomita

Is it possible to use the large cogs (I believe 3 of them are attached each other) from a Shimano 10 sp and use as large cogs on a Shimano 11 sp cassette?
Probably will use the following cogs as well to avoid any big jumps.
I am looking to have a bigger cog for some step hills - current one is 32T - and wanted to have a 34 or 36T as the bigger one.

Crankycrank

No. The cogs between 10sp and 11sp have different spacing. The cogs themselves are the same thickness so if you can find loose cogs with the proper 11sp spacers it will work.

tomtomtom123

Well, it's possible but he would just have to use the appropriate spacers. If the Shimano cassettes are riveted together, you can drill them out to get the cogs loose. But there is a lot of missing information. Like, how many speeds are you trying to build? 10 or 11? Which cassette do you already own? Why do you want to mix 10 and 11 speed cassettes instead of mixing 2 sets of 10 speed cassettes, or 2 sets of 11 speed cassettes?

Also, some of the higher end models from Shimano have the large sized cogs riveted to a spider, so you can't separate them. You should have a look at the exploded diagrams to see which cogs are on a spider. Look for the diagrams here by typing in the model number:
https://si.shimano.com/#/

Also, some cassettes don't mix well with each other, causing shifting problems. And I assume there is less compatibility when mixing cogs from 10 and 11 speeds, instead of mixing 10 speed with 10 speed and 11 speed with 11 speed. Also, The largest cog on the inner most position may have different offset and spacer thickness between the 10 and 11 speed cassettes. So if you're trying to use an 11 speed last position cog on a 10 speed setup, you might get incorrect total cassette width. You could solve this if you only mix 10 speed cogs for a 10 speed setup and 11 speed cogs for an 11 speed setup. (So what is the reason you want to mix 10 and 11 speed cogs?)

Also, 11 speed MTB cassette and 11 speed road cassette have different offsets on the last position cog. 11 speed MTB cassette last cog has a greater offset so that the entire cassette can fit on a 10 speed freehub. While the 11 speed road cassette needs the longer 11 speed freehub with the extra 1.85mm length. That's why if you try to use an 11 speed MTB cassette on an 11 speed freehub, you have to add the 1.85mm spacer as if it were a 10 speed cassette. But 11 speed road cassette cannot fit on a 10 speed freehub.

I mixed my own 10 speed cassette using cogs from 3 different Shimano 10 speed cassettes. Some combinations did not work, so I had to switch a few of duplicate cogs around until a got a good combination.

Miche also sells custom mixes of cogs. 11 speed anything from 11-34T. They also have 10 speed, but the last position only goes up to 30T.
https://thecycleclinic.co.uk/product...r-shimano-sram
https://www.miche.it/en/prodotti/str...mato-10sh.html
https://www.miche.it/en/prodotti/strada/cassette-pignoni/light-primato-11sh.html
https://www.miche.it/pub/media/productattach/t/a/tabella_compatibilit__primato.pdf

Here you have the list of all the current Shimano models for 11 speed road cassettes up to 34T. You still have to check which cogs are connected to a spider.
https://productinfo.shimano.com/#/sp...tte%20Sprocket

phtomita

Thank you for detailed explanation!
I have a 5800 11-32T - I think I will just get a new 11 speed with 34T.
I saw a cheap 10 speed 11-36T and was thinking if it was possible to mix it up - but then I would need the big cogs that are riveted and per above will have different spacing.

shelbyfv

Yes.