Originally Posted by
andr0id
That's the only thing I can think of.
They are compatible within 9/10/11 groups and I run a SRAM cassette on my tandem with everything else Shimano.
ok thanks for confirming,... I might try to play around with derailleur adjustements after this weekend's ride,... or just go back to my 12/25 and forget about this all until my next hilly ride
Originally Posted by
lostarchitect
Did you attempt to adjust the derailleur at all?
Not really, I mean, not beyond the B-screw setting.
Originally Posted by
dsbrantjr
Is your derailleur capable of a 28-tooth cassette? Not all are.
I always count on readjusting my derailleur whenever I change cassettes, even like for like, due to manufacturing tolerances.
It is likely that your B-screw adjustment needs to be changed when you change the cassette for one with different numbers of cog teeth; perhaps this is why the 27-tooth cassette ran OK but not the 28.
If you are going to put a larger cassette on you must be sure that your chain is long enough that you can comfortably shift to your large ring/large cog combination without straining anything. Test this while pedaling gently by hand.
Yes, SRAM documentation says maximum is 28t.
The B-Screw had been adjusted.
The chain is long enough. As I said, I voluntarily sized it a few links too long when sizing it for the 12/25 (thinking about using it with larger cassettes). And, FWIW, when I put the 53/28 speed which is the one requiring the most chain length, the rear derailleur is extended but not fully, there is still some room for a little more (which is one of the criteria for a perfect chain length sizing, though there are several methods, I know..)