11-34 or 11-28?
 

I'm in the market for a new endurance road bike. Looking at 105 level.

The area I ride in is more rolling than flat or major hills. Last ride was 31km and elevation gain was 280m. pretty typical for my rides.

I ride on a 10 speed Tiagara now with an 11-32 cassette and a 50/34 crank set. I ride 90% of the time on the 50 ring and rarely use the 3 biggest gears on the cassette. In the rare times that's not enough, I usually drop to the 34 ring to avoid cross-chaining, instead of using the biggest gears on the cassette. But I do find that I'm often searching for an 'in-between gear' on the flats.

So, I'm thinking of 11 speeds on an 11-28 would be a better fit. Am I missing anything?? (unless I go to a crank with a 52 then the 11-34 might make more sense?)

If you're on the same 50/34 and aren't really using the 34T, then go for the 11-28. For most people and most roads, a 34-28 bottom gear is enough. If you ride for a bit and find it's not low enough, then you can always replace the cassette easily enough.

You can get an 11-30T cassette in Shimano 11-speed if that's a better option for you (my preference, just for that extra gear if I hit an unexpected steep pinch or am weak/tired).

Going from 50 to 52 is a 4% gear change. Going 28-34 is a21% change. And you aren't even using those biggest cogs with your 50/52. If it were me, I'd keep the 11-28 and maybe simply downshift to the inner ring a little more often.

50 crank 12s 11-34

If you get DI2 with your new bike, it will automate shifting down to the small ring (if you choose that particular setting) and you'll find you use the full gear range more easily.

Also, I think 105 is now 2 X 12.

I went through a similar dilemma when I got more into road riding during the pandemic. My bike originally came with an 11-speed 11-32 cassette with a 50/34 crankset, and I just was not comfortable with the gaps in this cassette. Like you, I was always hunting for an in-between gear on relatively flat terrain. So I swapped from 11-32 to 11-28 to 12-25 to 12-28. In the process, I became a gearing expert, reflecting my narrow power band (otherwise known as cadence intolerance here on Bike Forums).

In your case, comparing (A) a 10-speed 11-32 cassette to (B) an 11-speed 11-28 cassette, both driven by a 50/34 crankset: Bicycle Gear Calculator (gear-calculator.com)

Assume that you cannot use the 3 or 4 physically smallest cogs of the cassette with the 34T chain ring, then compare the respective gaps between the two drivetrains, especially at higher velocities. (A) has many more gaps than (B). On (B), the only significant gap for most people is the 17T to 15T gap in the cassette when on the 50T chain ring.

However, as you are considering a whole new bike (rather than just buying a new cassette), just buy the bike you want with the crankset you want, then swap the cassette later if necessary. In other words, do not let the installed cassette deter you from the bike you want.

The bikes I'm looking at are still 2X11. Also, budget is mechanical level.

So, you need only replace the cassette? I thought chain and derailleur would also be impacted, though I'm not expert here.

In Shimano's latest (i.e., 105 R7000 and Ultegra R8000) 11-speed drivetrains, a medium cage rear derailleur handles up to a 34T max cog, while a short cage rear derailleur handles up to a 30T max cog. However, you can still use a medium cage RD with a smaller (e.g., 11-28 or 12-25) cassette, you just have to loosen the B screw as much as possible and shorten the chain.

so If I get a new bike with a 32 or 34 max cog cassette, I can swap later to a 28 and if I don't like that, swap back. That seems pretty straight forward. Thanks!

I ran both a 12-25 and a 14-28 on my 11 speed di2 with the mid cage replacing the 11-34, and I did not need to adjust my b screw that much, a couple of turns was all that was needed, so just be mindful of you individual need. As far as the chain, if I recall correctly, it was 3 links, could have been 4, but it's been a while, and I am old.

Edit: Sorry mid cage, not long.

I find that a lot with 50/34. At normal speed on the flats I feel like I'm cross-chaining one way or the other, and shifting the front a whole lot more than I do with 53/39, or 52/36. If you only have rollers, and no walls to climb, 34x34 is a waste. I don't even use 36x34 all that much, and I live in a hilly area.

Your last ride is about 45 ft/mile of climbing, which compares pretty well with my 21 mile route which is about 46 feet/mile. I think of that as my flat route, versus the 55 ft/mile of my usual Sunday long rides. So if you're only doing 45 ft/mile, you don't need wallclimbing gears and really don't need a compact crank. I'd consider the 52/36 and an 11-28 or 11-30.

This.

And for $45 you can get a second cassette, and for not much more you can get the tools to swap them.

I with a 52/34 I run a 11/30 rear 90% of the time. No issues with rolling terrain and short/steep spikes. For mountains or heavier climbing days I simply swap the 11/34. Takes 5 min max, and you can clean your cassette in the process.

Cassettes can be had for under $100. The rear rear dearuiler that you are looking at for either bike should be able to handle 11-28 or 11-34. So just get the bike you like better.

I looked at all the 11 speed cassette options a few years ago. I ride rolling terrain, with multiple 1 mile / 1.6 km climbs of 300 feet / 100m. So I use the 34F-32R a lot!

Like you, I was always shifting up--too hard, then back down--too easy, on fast rides, fairly flat group rides. I built a 14-32 from a 14-28 Junior cassette and a 11-32, for those fast group rides. It worked great for me, with very close shifts. But it needed two or three cog shifts quite often, since they were very close together. And I shifted the chainrings a lot. This worked fine with my Di2, but would be annoying with mechanical. It was 14-15-16-17-18-19-20-21-24-28-32!!

11-32 works fine with my short cage Di2. In general, most riders find they can use cassettes outside the recommended range for the derailleur. Just make sure the chain is long enough, and do a careful test on the bike stand: from mid cassette, shift to the big ring, then "carefully" shift to the largest cog. You need a small amount of clearance to the top pulley, and the chain needs a jog in it, not stretched straight between the pulleys.

In 11 speed:
The 11-32 cassettes from Shimano and Sram are quite similar.
But, Sram's 11-28 works better at the higher speeds, with closer shifts. Shimano's 11-28 is better for cyclists at a moderate speed.

From Mike Sherman's Gear Calculator (recommended! Click Save to make a URL for the current view to recall it later. All the changes update as you edit the numbers. )

~~~

Shimano 11-28 and 34/50 front, at typical flat road cadences. 50 chainring in black, 34 chainring in red.
Good in general, but it has quite large shifts in the 25-40 kph range. It's biased toward the larger cogs, very good for more casual riders.
Link to the Gear Calculator Shimano 11-28

https://cimg6.ibsrv.net/gimg/bikefor...eaca56f91a.jpg
~~~

Sram 11-28. Note the closer shifts above 30 kph (19 mph) and also close shifts from 20 kph (12 mph) to 30 kph.
Link to Gear Calculator Sram 11-28
https://cimg0.ibsrv.net/gimg/bikefor...50e0d648d0.jpg

~~~~~~~~~~~~~~~~~~~~~~~~
For comparison:

Your 11-34 10 speed Shimano, with 50/34 at the same cadences:
Much bigger gaps between shifts at the higher speeds! Wow!

https://cimg0.ibsrv.net/gimg/bikefor...f28764acd1.jpg

I did! I bought one each of:
Cassette Wrench - 1670/2BI-US – Unior USA
Shimano/SRAM Cassette Lockring Tool with Guide Pin - 1670.7/4 – Unior USA
Cassette Lockring Tool with 12mm Guide - 1670.9/4 – Unior USA

Saying bye bye to old Park Tool 5.2 lock ring tool and chain whip.

52/36 vs 50/34 is just a 4% harder gearing in the big ring. That's about half a shift. (Percentages for a cog shift: divide the two cog teeth numbers: 16/15= 1.066 or 6.6%, for example. 15/13 is 15%. 6% to 12% is typical for a lot of gear shifts.)

A lot of cyclists that have hilly terrain would benefit from a smaller crankset than the typical 50/34. 46/30, for example, lowers all the gears 9% in the big ring, 13% in the small ring. Useful.

If you're looking for "in between" gears and don't need your largest cogs, getting a smaller range (and more gears to boot) makes perfect sense.

My main bike is a 2x11 that originally came equipped with the 50x34 crank, and 11-34 Shimano HG800 cassette.

I absolutely hated that cassette. On flat pavement, in still air, I'm comfortable holding 50x15 @ ~80rpm, but as soon as the grade shifts slightly, or there's a headwind, I need to downshift - but the next gear is a 17, which is just too big of a gap. Likewise, on a slight descent, I'd love to hold 50x14, but I have to stick with 50x13 (just a little too hard), or 50x15 (spinning faster than I'd like).

On the other hand, I have a short, 9.8%, 0.5km grind to get to the local MUP. Even on that, I never used 34T, and rarely the 30T - I was fastest grinding up that climb in 34x27. This is in-line with my experience on my other bike, where I would go up a 6% 1.5km climb in 32x25 or even 32x22 - never needing that bike's 27T granny gear until I took her out to CA - 2km @ 13.4% or 9% at the tail end of an 8km, 7% avg...

Having both of these experiences, I replaced the 11-34 HG800 with a Miche 12-29. I've never gotten the shifting to be quite as crisp as the Shimano cassette, but I have every gear between 12-17, and the 29T still gives me a 7% lower gear than I typically use. I also have a SRAM 1170 11-28, which is similar to the Miche, but is slightly more cruising focused (fewer climbing gears). The SRAM shifts better, but I'll trade that for the Miche's gear range.

My recommendation would be all else equal, pick the bike with the 11-28 gearing, as it sounds like you're not likely to want/need more. That said, if you like everything else on the bike with the wider gearing, go for that bike - if you don't like the 11-34 after a couple of rides, there are definitely other options that can be installed for very little money.

Can someone list all of the gears on both the 11-34 and the 11-28 cassette? Is there a standard? That would help answer the question, but OP I don’t think it matters people care about what gear they are in too much.

There's no standard. The Shimano R8000 11-28 skips the 16T, but the SRAM 1170 11-28 includes it. The R8000 includes 21T and 23T, which the SRAM trades for a single 22T.

Miche has individual cogs without a spider/carrier, which allows one to pick and choose.

I care a lot about my gearing, actually - I need a corncob from 12-17, but rarely use 11T. I've regularly used up to 27T, and when I'm feeling weak/tired/slow (name your excuse), I'm happy to have 28-30T. On my 11-34, my 34T is much, much shinier than my other cogs.

Exactly, with respect to road riding. The 11-34 cassette was originally designed for mountain bikes and has since been surpassed by even the wider range 11-40 and 11-42 cassettes. Given my experience with the 11-32 cassette, I thought I was going to hate the 11-34 cassette that came with my gravel bike, but in that application it works very well. The larger gaps at the smaller end of the cassette allows more gears at the bigger end, which allows better finetuning of climbing cadence.

Sounds like you need an 11-speed 12-28 cassette, which is my holy grail, so much that I bought two.

Of course you would not care much about gearing, given your ability to wait at the bottom of a hill for another cyclist to go past just to chase him/her/them down and blast past him/her/them with your glops of power.

For and endurance bike with clearance I started with the 11-34. For rolling hills the step just did not seem right. Switched to 11-28 and much better. But kept the 11-34 for mountains. Then after a year picked up a set of carbon road wheels 51 deep and run road tires. Use the 11-28 on these. Put 38mm gravel tires on the stock aluminum endurance wheels with the 11-34. It’s great having two sets of wheels. One for all road and the other for casual rides and gravel roads.

Either way get a bike with enough tire clearance for future versatility.

I’m partial to the Domane but I have one. Checkpoint for even more clearance.