Saltlydog4 said:
I was thinking of going with a 12-28 cassette but am wondering if its overkill. Right now the 11-21 just makes some of the climbs here miserable. How much would a 34t upfront help instead of the 36? I want to try and avoid overlap as much as possible so I need help there as well.
I was going to say "you mean 11-28 cassette, not 12-28"... but turns out, whoa, SRAM
is offering 12-28 now. And the ratios look pretty good actually- you get the 28t, but without losing the 16t. Nice! :yesnod:
Far as your situation goes, it's difficult to prescribe exact gearing for someone else, considering that so much of it is up to a rider's individual fitness level, preferences, riding terrain, etc. etc.
It's like, just how badly are you getting jacked up by your current climbs? If it's just somewhat, then maybe 12-25 might be ok. Lots of ppl like that cassette because you have the 16t cog and no large jumps. But if you're getting absolutely
totalled by your climbs, then 12-28 starts to look real good, and you shouldn't worry about getting it, assuming it will work with your drivetrain.
On chainrings... Julius is right when he says 34t inner chainrings aren't that expensive (it's the big chainring that is seemingly made of gold, considering what the parts makers charge for it

), so that could be another good change. By itself though, it isn't getting you that much lower of a low gear... for you, it'd be about the same level of change as if you'd gone to a 22t large cog in the back, i.e. not much better.
If you're terribly budget-squeezed, then perhaps do the cassette change by itself first, and then assess from there.
Btw, how old is your ultegra rear derailleur? The older ones didn't have quite as much chain wrap capacity (though often you can get away with exceeding the spec slightly), while the newer ones were designed to work fine with big chainring differences (50-34) plus wide-range cassettes (even 11-28).
So, if it's an older rear derailleur and you wanted to go 50-34 up front, it might be that the 12-28 isn't an option, at least not without exceeding the spec a little bit. Some ppl are fine with trying things that are a bit outside of spec, but others get nervous and worry that something's going to break, even though that's pretty unlikely.
If it were me, I'd just put on a 12-28 cassette (the one that goes 21-24-28 on the last three cogs, not the weird one that goes 21-23-28), and then assess if that's enough (as a bonus, with 50-36 up front, you shouldn't be exceeding spec). If it's not enough, then I'd spend the xtra $$ on getting a 34t small chainring.
/ and I wouldn't sweat it if the 12-28 ends up being 'overkill', low gear-wise... there's always going to be days when you're not at your best, or you've been dealing with headwinds all day, or you do an extra-long ride and are just totally beat but still have big hills to climb to make it back home.
Times like those, having that one extra 'overkill' bailout gear that you don't normally need can be a godsend.
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