I was doing a bit of research for possible casette combinations and wanted to see if there are ways of decreasing my maximum gear inches, which led me to the Shimano Deore casette. However, I was a bit confused by how they are designated, because each of the different combinations is followed by a bs, bt, or bu letter combination and I am not sure if this is an abbreviation for something, or if it otherwise means anything that should make me concerned about compatibility. Haven't been able to find any information out there.
Let's say I currently have a Shimano 11-speed 11-32 casette. Would the bs, bt, or bu mean anything that is relevant for compatibility?
https://bike.shimano.com/en-EU/product/component/grx-11-speed/CS-M8000.html
by smoelf
3 Comments
Those designations are inconsequential. I believe they have something to do with what cassette cogs can be mixed with each other (and the fact that the designators are different means you cannot make up some frankencassette by mixing and matching cogs from e.g. a 11-42 and 11-46 cassette).
If you currently have an 11-32 cassette your derailleur probably doesn’t have the capacity to shift a 11-40 (or -42 or -46) cassette.
That’s their coding for the different cassettes, ignore that lol, just look at the gears you get and you’ll be right 🙂
The page you’re linking to explains the difference:
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https://preview.redd.it/ubrrues7mr1d1.png?width=1432&format=png&auto=webp&s=a3e43a4a6c91ec650009ff10f125ad43ec9ab75d