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I've searched, but can't find much directly on point.

Briefly: I'm about to finally upgrade from the DA 7800 drivetrain i've been using for the last decade. Time I let go of my grouchy old man ways and get hip to the new stuff. That said, as I'm looking at 11 speed options these days and compact gearing, I hear about large chainring jumps being less than seamless to those of us who are so used to ratios that we've been on for the longest time...

I'm looking at the Shimano 11 speed road offerings and seeing several options for standard, compact and mid compact with options for 14 tooth jumps (39/53 and 38/52) and larger jumps of (50/34 and 52/36) teeth.

I've historically been mostly a flatlander, so 53/39 has been great, though I've been riding more hilly terrain in the last several years AND i'm older and riding less than I used to. Enter the compact thoughts.

Gear calculations and front shifting performance (debateably) aside, why is 50/36 not a popular "stock" option for gearing to preserve the 14 tooth jump between chainrings? When i take a look at other popular compact ratios that have 16 tooth jumps, it seems like there is an inevitable gap-gear range that would require crosschaining or lots of front and rear shifts to keep momentum as terrain changes.

So basically, for someone who is getting older but wants to keep the same basic front gearing spread, but just lower overall, why wouldn't 50/36 be ideal with maybe a spare "rainy day" cassette with a larger 28t cog in back for climbs etc when needed? Seems like this would effectively be a downsized version of 53/39 and 12-23 or 12-25 that I've known forever, only slightly lower across the board overall.

Is my thinking off on compact gearing? I'd be fine just getting an 11 spd shimano crank and swapping a chainring to make this combo, but just wondered why I haven't seen more about this through my research. Thanks for reading.
 

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It's the missing 18t cog that screws up the gearing spacing and the 50something/18 is right in the sweet spot for older former fast guys on the flats. At least with 11 speed cassettes you can keep the 18 on a 12-25 and not have any gaps on a 52/36
 

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I went from a 50/36 where I would run an 11/23 10 speed (in flatter areas) to 52/36 with 12/25, 11 speed and like the slightly closer gear spacing. I am running DA9000 and find no issues shifting from chainring to chainring.
 

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wants to keep the same basic front gearing spread, but just lower overall, why wouldn't 50/36 be ideal with maybe a spare "rainy day" cassette with a larger 28t cog in back for climbs etc when needed? Seems like this would effectively be a downsized version of 53/39
I think your thinking is right, but just be more precise about it, you should pay attention to the ratios, not the absolute tooth differences. 14 teeth is not the same if the ring sizes are different. To duplicate 53/39, 50/37 is closer. 49/36 is also closer than 50/36. The old "standard" was 52/39, and 36/48 is exactly the same ratio.

The chainsets sold as compact or mid-compact don't make a lot of sense to me in terms of shift patterns. Those large jumps are awkward.
 

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The compact or mid-compact makes sense if you need the low gearing. The larger spread between the chainrings is no problem. You just shift one more cog when changing chainrings. It's not difficult.

But if you don't find yourself wanting lower gears than 39x28 (or have epic mountains in your future) there's not much point in going compact. I find that on flat land the smaller 50t big ring is more useful and it's extremely rare that I want a higher gear than 50x11.

I suggest finding your favorite gearing calculator, looking at gearing charts and comparing to your current setup.
 

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It's easy to overthink this.

I believe you just have to commit to a gearing scheme and give it a try. You can always change it. It's easy and relatively inexpensive to swap chainrings on the current Shimano drive trains.
 

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50/36 is just a stupid compact ratio. I've been using 50/34 on most of my bikes and 53/39 on one. The 50/34 is a little pain if constantly transitioning above and below 20mph. I just ordered a new frame and I'm going with Ultegra Di2 with 52/36 up front and 11-28 in back. I'm hoping it will work out well
 

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Shimano design the shift ramps/ pins as a matched set for 50/34, 52/36, 52/38, 53/39 etc to optimise shift performance. I dont know if there is any noticeable difference when using combinations outside of these matched pairs though, I'm sure it will shift. I have 52/36 & 11-28, 11 speed, ride hills, love it.

Shimano's FD is designed to take a max of 16t chain ring difference.
 

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50/36 is just a stupid compact ratio...
In your opinion. With my old ride I wanted a compact 50/34 for trips to hilly areas like California, but the 34 was pretty useless in SE Wisconsin. The 36 was much better suited. With gearing there are too many variables to make blanket statements. I have two sets of chainrings (52/36 & 50/34) and 4 cassettes so that I can tailor to wherever I will be riding.
 

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I'm also an older guy (I'm 50) in a hilly area, and I find 52/36 works just fine. I should add that I am less fussed than most about small gaps on the cassette, so I'm happy to leave a wide range cassette on the back. The best way must be to borrow or rent a bike with the ratios you think you want, and go for a spin on your usual routes.
 

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why not wait a few months. Shimano is set to come out with their new gear set and one of the rumors is that it will be 12 speed, which if true will cut down on the jumps in the rear cassette. You could do semi-compact with a 32 cog and get the best of both worlds, not common but it would give you the escape gear when tired and climbing.
 

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why not wait a few months. Shimano is set to come out with their new gear set and one of the rumors is that it will be 12 speed, which if true will cut down on the jumps in the rear cassette. You could do semi-compact with a 32 cog and get the best of both worlds, not common but it would give you the escape gear when tired and climbing.
12 speed? Seriously? I thought we were done with this
 

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I have found a 52/36 up front with an 11-25 in back is perfect for my riding. I deal with l lots of hills and it meets my needs. I had an 11-28 on my Tarmac but found I just did not need the 28 so I matched up both bikes. I did ride a 10 speed with 50/34 and 11-25 and it was ok but seemed like the 34 ring did not get much use. I would guess I am probably conditioned to what I have for he most part. I can say I prefer the mid compact over a triple for sure.
 

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Yes, but you need a long cage rear derailleur, which rules out Dura Ace for that part.
That is not necessarily correct for 11 speed. I can run a 32 on my Domane with DA9000 (standard cage) with no issues. If need be, one could always could swap the cage on their DA9000 to the longer GS cage from an Ultegra derailleur.
 

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It's a serious rumor floating out there. Heard both from very knowlegable local bike shop and seen some chatter on forums. Not official and it may not happen, but if it does probably won't require new wheels and it may be available for only electronic shifting(something about the ability to accurately shift in smaller increments).

12 speed? Seriously? I thought we were done with this
 

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My goal was to keep my RPM above 85 on a 7mi 6% climb. Since I am a weekend warrior and not increasing my pwr/weight ratio fast enough I lowered my gearing. I have a 50/34 with a 12/28 (usual) or a 12/32 for long days of climbing. Why not, the worlds best climbers use similar gearing?

Since I don't do a lot of group rides or any racing I don't need to push 50x11 or 53x12 in a sprint. The 16t is way more useful than the 11t and the 50/34 crank is more suited to my riding. I put a triple (used as a double (39/28) with a 12-36 cassette on my cross bike for long and steep dirt back roads carrying camping and/or fishing gear....
 
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