# Any noticable difference in 12-27 vs 11-28??



## MJCBH (Nov 25, 2002)

I currently run DA 7900 50-34 with a 12-27 Ultegra rear cassette and am thinking of switching to a 12-28 (which I will most likely have to do in the future anyway since apparently shimano is not making the 12-27 anymore). For climbing and on flats, do you think 1 cog is going to make that much of a difference? I previously had a triple set-up and really liked it for climbing.


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## cxwrench (Nov 9, 2004)

not sure why you think you can't get the 12-27 anymore, it's in stock at QBP and any shop can order it for you if they don't have it. 
as for the difference between 11-28 and 12-27...at the low end it's a pretty small difference between the 27 and the 28, you probably won't notice it. at the high end it's nearly 10%, so the 11 is a much higher gear than the 12. 
the cogs on the 27 look like this...
12,13,14,15,16,17,19,21,24,27
and the 28 is like this...
11,12,13,14,15,17,19,21,24,28
you do give up the 16 cog on the 28, but unless you're really finicky about that one cog, you should be fine.


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## nightfend (Mar 15, 2009)

27 to 28 is a small difference, you won't really notice it. But the 11 could possibly be useful if you are a racer. Otherwise I think the 12 is fine.


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## kbwh (May 28, 2010)

Loosing the 16 is big. I dislike the big jump between 17 and 19 too...


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## jwp3476 (Jun 22, 2010)

Normally there is a 3 cog change with a 12-27 cassette when changing the front ring with a 39-53 crankset. I found that I needed to shift 4 cogs on the 12-27 cassette frequently when shifting to and from the big ring with a 34-50 compact crankset but only 3 cogs with the 11-28.


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## ericm979 (Jun 26, 2005)

Shimano stopped making 12-27 ultegra. It's still available in Dura-Ace, but the cost is high. They're not worth using for training.

However Sram makes 1070s in 12-27 and they work well with Shimano derailleurs. They won't fit on 10sp freehubs that have the tall splines, but those were only on some Shimano hubs and a couple after market hubs. The large majority of Shimano style hubs accept Sram cassettes.


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## danl1 (Jul 23, 2005)

ericm979 said:


> Shimano stopped making 12-27 ultegra. It's still available in Dura-Ace, but the cost is high. They're not worth using for training.


Still available as 105.


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## Guest (Jan 23, 2012)

Do you have a compact or standard crank?

I have the 11-28 on mine, but that's because I have a 50x36 crankset. 50/11 is basically the same is 53/12, and 53/11 is widely considered overkill for almost all riders.

Check out a gear-calculator to see the differences:

 11-28 setup w/ 50x34 
12-27 w/ 50-34


The 12-27 gives you the 16t intermediate cog. The 11-28 gives a faster top-end, and allows you to develop more speed from the small-ring without cross chaining.


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## FBinNY (Jan 24, 2009)

You won't notice much difference between a 28t ans 27t low. Most times once you're in low gear you're just doing whatever it takes to get up the hill. The added 3% or so might help slightly.

The problem is at the other end, and really depends on which gears you use for general flat riding which is about 80-90% of the time. If you rarely ever used the 12t, you'll now have one more wasted gear. It come as a cost of a wider jump farther up the line, and if you ride the now missing gear routinely, you'll miss it. 

There's also the issue of the mid range gears being pushed inboard one position. If you spend lots of time on the outer chainring, in the upper middle of the cassette, then some of those combinations will be now be somewhat crossed over more, and will run noisier and cause increased chain wear.

OTOH- if you spend lots of time on the 12, 13, and 14t sprockets, you'll have a nice addition to your range for those long shallow grades and/or tailwinds.


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## new2rd (Aug 8, 2010)

I'm searching for the exact same thing. 
I'm running a 50-34 with 11-32. 
My issues with the 11-32? I wish I had a 16t and I don' t like the 19-22 jump.
The best solution seems to be the 12-28 SRAM 1070 w/
12-13-14-15-16-17-19-21-24-28
or
12-13-14-15-16-17-19-21-24-27 (I think I would rather have the extra tooth of a 28 even if the differnce is small).

My concerns are losing the 11t. I know there's some kind of calculation out there, but can't I get the same speed in a 12 by pedaling a few more RPM's? I don't live near mountains so I don't plan on spinning at 140 RPM's down hills.


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## new2rd (Aug 8, 2010)

PhotonFreak said:


> Do you have a compact or standard crank?
> 
> I have the 11-28 on mine, but that's because I have a 50x36 crankset. 50/11 is basically the same is 53/12, and 53/11 is widely considered overkill for almost all riders.
> 
> ...


Using a 50/34, I find that the small ring is only used for hills or against the wind. What do you consider cross chained? Small chainring to the two smallest cogs.. three smallest? I ask because everyone seems to have a different opinion on this.


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## kbwh (May 28, 2010)

Try putting your cassettes and chain rings into this:
BikeCalc.com - Speed at all Cadences for any Gear and Wheel
Or even better. This one is marvellous:
http://www.gear-calculator.com/


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## redondoaveb (Jan 16, 2011)

new2rd said:


> I'm searching for the exact same thing.
> I'm running a 50-34 with 11-32.
> My issues with the 11-32? I wish I had a 16t and I don' t like the 19-22 jump.
> The best solution seems to be the 12-28 SRAM 1070 w/
> ...


I was running a 12-25 but have recently switched to a 12-27. I could climb everything with my 34-25 but had to do a lot of standing in the really steep sections. It's nice having the 27 just in case. I don't miss not having an 11 but that's just me as I can't push an 11 on the flats anyway and by the time I spin out the 12 downhill, I'm in a tuck and not pedaling.


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## jnbrown (Dec 9, 2009)

I definitely notice the difference between 27 and 28 on steep hills.
I really like my SRAM 12-28 because the three top cogs are 22-25-28.
It doesn't shift so well so I am planning on getting Shimano 11-28 and 12-25 swap the the cogs to make a 12-28 and sell the rest as 11-25. Would rather have the 16T instead of the 11T.


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## jwp3476 (Jun 22, 2010)

jnbrown said:


> I definitely notice the difference between 27 and 28 on steep hills.
> I really like my SRAM 12-28 because the three top cogs are 22-25-28.
> It doesn't shift so well so I am planning on getting Shimano 11-28 and 12-25 swap the the cogs to make a 12-28 and sell the rest as 11-25. Would rather have the 16T instead of the 11T.


When you get both cassettes, look at the pattern the teeth make. Each is supposed to be optimized for easy shifting. After you swap individual cogs, see if the pattern is the same. I tried to mate an 11-23 with a 12-27 and they just didn't look right when I was finished. I didn't try to ride it but I suspect the shifting would not have been too good.


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## jnbrown (Dec 9, 2009)

jwp3476 said:


> When you get both cassettes, look at the pattern the teeth make. Each is supposed to be optimized for easy shifting. After you swap individual cogs, see if the pattern is the same. I tried to mate an 11-23 with a 12-27 and they just didn't look right when I was finished. I didn't try to ride it but I suspect the shifting would not have been too good.


I would be swapping the lower 7 cogs, 11-19 with 12-19.
In both cases you end up with 19 next to the existing 21 T cog so I don't see why it would not work perfectly.


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## Bocephus Jones II (Oct 7, 2004)

MJCBH said:


> I currently run DA 7900 50-34 with a 12-27 Ultegra rear cassette and am thinking of switching to a 12-28 (which I will most likely have to do in the future anyway since apparently shimano is not making the 12-27 anymore). For climbing and on flats, do you think 1 cog is going to make that much of a difference? I previously had a triple set-up and really liked it for climbing.


It's one more

<img src=https://deadcowgirl.com/wp-content/uploads/2011/06/spinaltapamp.jpg>


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## jwp3476 (Jun 22, 2010)

As I said, look at the pattern the cogs make before and after. The 19 from one and the 19 from the other may be in the same orientation which may affect the shifting.


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## Guest (Jan 23, 2012)

new2rd said:


> Using a 50/34, I find that the small ring is only used for hills or against the wind. What do you consider cross chained? Small chainring to the two smallest cogs.. three smallest? I ask because everyone seems to have a different opinion on this.


I consider two-smallest to be cross chained/should always be avoided. I _usually_ avoid the third smallest (36/13) but don't sweat that one as much. I'll use 36/13 if, say, a climb levels out brieftly then starts ramping up again and I don't want to front shift twice. 

For the big-ring, I avoid the two largest (50/24 and 50/28) but use the third largest (50/21) frequently. However, unlike with the small ring, big-big cross chaining can actually be done on my bike without producing rubbing if I trim the front derailleur. I still prefer the two largest cogs if I can though. 

My optimum cadence for steady-speed riding is around 110rpm, so this means I use the big ring only if going over 20mph for an extended amount of time (50/21 is 20.3mph @ 110rpm). For seated climbing I'm usually more like 90rpm cadence. Out-of-saddle climbing often lower still. Overall I probably spend roughly equal amount of time in one ring or the other.


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## baker921 (Jul 20, 2007)

new2rd said:


> I'm searching for the exact same thing.
> I'm running a 50-34 with 11-32.
> My issues with the 11-32? I wish I had a 16t and I don' t like the 19-22 jump.


Or you could run a triple and have it all; except your street cred of course!

I totally get running a compact over a triple but not at the cost of a MTB cassette which implies you want the full range of gears offered by a road triple.


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## new2rd (Aug 8, 2010)

redondoaveb said:


> I was running a 12-25 but have recently switched to a 12-27. I could climb everything with my 34-25 but had to do a lot of standing in the really steep sections. It's nice having the 27 just in case. I don't miss not having an 11 but that's just me as I can't push an 11 on the flats anyway and by the time I spin out the 12 downhill, I'm in a tuck and not pedaling.


I just ordered a 12-26 from my LBS. I wasn't too sure about the 26 vs. a 27 or even a 28, but the owner who I completely trust gave me the advice. Since we only have one steep section in the area, I can handle being out of the seat in a 23 or 26 for the short time. Now if I lived in the mountains it might be another story.


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## new2rd (Aug 8, 2010)

PhotonFreak said:


> I consider two-smallest to be cross chained/should always be avoided. I _usually_ avoid the third smallest (36/13) but don't sweat that one as much. I'll use 36/13 if, say, a climb levels out brieftly then starts ramping up again and I don't want to front shift twice.
> 
> For the big-ring, I avoid the two largest (50/24 and 50/28) but use the third largest (50/21) frequently. However, unlike with the small ring, big-big cross chaining can actually be done on my bike without producing rubbing if I trim the front derailleur. I still prefer the two largest cogs if I can though.
> 
> My optimum cadence for steady-speed riding is around 110rpm, so this means I use the big ring only if going over 20mph for an extended amount of time (50/21 is 20.3mph @ 110rpm). For seated climbing I'm usually more like 90rpm cadence. Out-of-saddle climbing often lower still. Overall I probably spend roughly equal amount of time in one ring or the other.


I feel the same way, although I'm not too concerned about cross chaining from the big ring given the trim option on the Force FD. However, I don't make it a habit to stay in the cross chained area for a long time (more than a minute). My RPM's are a bit lower at the mid 90's to 100 and I'm hoping with the 12-26 cassette I just ordered that I can spend a little more time in the 34-15/16 area before going up to the 50-19/21. I do everything possible to avoid the three smallest cogs when I'm using the 34 chainring, but there are time like you said where you don't want to shift twice in a short time span (rollers). 

I appreciate the response.


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