Replacing cassette: Does it need to be tandem-specific?
 

Hi all,
I want to replace the cassette on our 2000 Santana Sovereign SE. It now has an 11-34 9-speed (the original Shimano, I presume). I want to try an 11-36 or 12-36.
*Aside* from issues with the derailleur (it's the original XT) and the chainrings (52/42/26) and chain length (who knows), is there a special version of Shimano cassette I should get, or do I simply buy an off-the-shelf 9-speed mountain-bike version?
Or just swap out the big cog to a 36?
Any recommendations for specific model cassette?
Thanks!

Both Shimano and SRAM off the shelf 9 speed MTB cassettes have worked out fine for us.

Thanks.
Like the Shimano cs-hg400-9?

As far asbo know, there is no cassette specifically designed for tandems. Things to consider mostlybare your gear ratios (which you are doing) and if the 11 t cog will fit on your hub. Some older hubs won't accept them, though according to the Sheldon Brown website ( tons if all kinds of esoteric and practical information) it is possible to modify an older hub.

To be honest, I've not yet encounted a hub that wouldn't take an 11 tooth sprocket, so maybe that is not a real concern.

I dont know if component life would be affected by going to 10 or 11 speeds. Certainly, chain and sprockets get narrower with increases in 'speeds.' My guess would be that 9 speed is adequate for the additional forces involved with tandem riding. 11 speed might be too 'delicate.' Anybody have any input on that?

I haven't personally used that particular cassette but I have no doubt it would work. I currently have SRAM PG 970 and PG 990 on our tandems, 11-34. Even though they are lighter weight cassettes they are still working fine.

The cassette is just a bunch of sprockets, and they don't care how you use them.

What may care I'd the free hub ratchet. Lower gearing means higher torque, and if you're climbing steep grades, you can approach the limits of three ratchet mechanism.

Most have plenty pfft reserve strength, but I've seen some fail strong climbers. Rare, but happens, though rarer yet with the well respected brands.

We *aren't* strong climbers, which is why we need those extra teeth!

No, most likely your existing 9 speed Shimano cassette uses a typical multi sprocket carrier ("spider") and so you cannot simply replace just the 34t with a 36t.

For tandem usage, try to get a cassette that has all cogs made from steel, not alloy. Steel will last a lot longer and less chance of bending one.

see:

https://www.bike-discount.de/en/buy/...0-11-36-625054

Thanks. That's exactly the cassette I was wondering about.

Pedantic engineering rant here: "Alloy" is likely intended here to mean "aluminum alloy".


All common metals used are "alloys", including steels.

++++++ :)

Y, sorry. I meant AL(uminum) but brain farted instead.

That said, plenty of mtb tandems are attempting to use the super wide cassettes of which most have a AL mega cog. Some have reported bending the 50t on a SRAM for example and I have seen a photo of the same with a tooth snapped off.

Don't feel bad. Despite "alloy" being used as shorthand for aluminum and other light alloys for generations, some folks still feel the need to "correct" people for it. ;)