Compact v semi compact

[TonyM]

I used to ride 52/42 and 53/39 (together with 11-21 to 12-26) in the old days. But I was young and quite strong also. At that time there was also no there options...

Now I use now a compact 50/34 with 12-25 almost all time. I used only the 12-28 for alpine courses in the Alps for example.

With the 50/34 and 12-25 I can ride almost all times on the flats and small/ short hills on the big rig and this is more convenient (and mor efficient than small ring and small cog). For me it works better like this.

If I had to use a mid compact it will also be ok but I will have to use a 12-28.

[topflightpro]

I have all manner of gearing at my disposal, but I will say the one combination of chainrings that I just do not like is the compact 34/50. It's not so much the gearing it provides as the jump. I would find myself shifting between big and small rings far too often, and even with a simultaneous shifting of 1, 2 or 3 cogs at the back I never really seemed to be landing in the "right gear". Versus with either the 36/52 or the "standard" 39/53 a quick change at the front with a simultaneous 2 cog shift at the rear and boom, I'm pretty much where I want to be. ..... I think the only time I would choose a 34/50 is if I knew I was going to be in the 34 for a great majority of the day. I prefer the 39/53 for most things.

This was my experience too. I just could not get comfortable on a compact. I have not tried mid-compact yet - I've done 52/39 - but I expect it would be a good option.

[pdlpsher1]

I have all manner of gearing at my disposal, but I will say the one combination of chainrings that I just do not like is the compact 34/50. It's not so much the gearing it provides as the jump. I would find myself shifting between big and small rings far too often, and even with a simultaneous shifting of 1, 2 or 3 cogs at the back I never really seemed to be landing in the "right gear". Versus with either the 36/52 or the "standard" 39/53 a quick change at the front with a simultaneous 2 cog shift at the rear and boom, I'm pretty much where I want to be. ..... I think the only time I would choose a 34/50 is if I knew I was going to be in the 34 for a great majority of the day. I prefer the 39/53 for most things.

This was my experience too. I just could not get comfortable on a compact. I have not tried mid-compact yet - I've done 52/39 - but I expect it would be a good option.

I don't understand what you wrote. You have all manner of gearing at your disposal but yet you cannot find the right gear. In my experience the 50/34 reduces the front shifts as I can stay on the 50 longer while riding on the rollies.

[Calnago]

I mean I have bikes with both 39/53 and 36/52 cranks. I also have a bunch of wheels with cassettes ranging from 11/23 to 11/29 and virtually everything in between. Hence all manner of gearing available and ready. I don't have any bikes set up with 34/50 simply for the reasons I wrote, in essence that this combo provides the most awkward shift patterns.

[fa63]

10 years ago, I was 80 kg and rode a lot, and did just fine with a standard crankset with a 11-27 cassette. Now I am 100 kg and don't ride as much, and I prefer to go up the same climbs with a compact and 11-32 cassette.

I remember when I first changed from a standard to compact; after a few weeks it felt normal. The body adapts pretty quickly.

I also tried a mid compact recently; felt similar to my compact crank in most situations but I found that I missed having my 34x32 gear in the mountains. That said, I will be using a mid-compact on a new "aero" bike I am building, and stick with compact on my "climbing" bike.

[AJS914]

I really like the feel of mid-compact. You can cruise around in the 36 if you want. With a 50/34 you'll end up quickly shifting towards the 50.

That said, I've been running 50/34 because up until recently Campy only made cassettes with a 29. I've adopted more of a sit and spin approach up climbs so I stuck with the 34x29. I'm now living in an area with less hills so I could probably get on fine with a 36x29 these days. I also use a 12-29. I sometimes miss having a longer gear for downhills but not often enough. I can live with it and I'd rather have 12-29 instead of 11-29.

Campy is coming out this year with mid-cage derailleurs for Chorus/Rec/SR so a mid-compact with a 32 in the back might be a good option in the future for me.

It all comes down to what gearing you want/need.

[alcatraz]

I see some posters use 12-xxt cassettes.

I'd just like to point out that the difference between 11t and 12t is equivalent to going from a 50t big ring to less than a 46t.

It tells me that I could go down to a 46t big ring and still enjoy gear ratios just as high as with a 12-xx cassette on a compact.

I'm a smaller rider doing climbs, sometimes steep. My rd is currently maxed at 11-28t. My dream crank is to run a 48/30t or a 46/28t but they are hard to come by (32t cassette is cool too although a bit heavy).

When that occasional killing 20+% grade comes I want the option to remain seated (we can have a bad day) and keep cadence at least at 80rpm.

With today's common braze-on fd's it's maybe difficult to lower it far enough to go 46t but it shouldn't be far off from a standard 50t.

FSA is now offering SL-K Modular Adventure cranks is sizes 48/32 and 46/30. Mixing parts and make a 48/30 sounds good to me.

[2lo8]

I tried 52/36 and I didn't like it because I would readily give up 52x11 for any other gear, midrange or low end or even just some more overlap and making the 1t range extend to lower speeds. It has the same big 16t jump as 50/34, which is physically the same 1.27" jump only only a slightly smaller ratio. The only reason I can imagine people would need to shift 3 cogs instead of 2 cogs with 50/34 vs 52/36 is not because the jump is smaller, but because they're triple shifting 1t gaps instead of double shifting 2t gaps and not changing rings in the same place on the cassette and covering a wider spread that way. Nor do I understand when people claim it they have to shift rings less unless they ride around in the 36 most of the time, as a smaller big ring or a bigger small ring means you can stay in it longer. If 34 is too small, I would would just increase the size of the small ring but keep the big ring small.

[shimmeD]

Before there were such a thing as compact or 11-speed, I ran 52/42 with a special 13-25. Now I run 46/33 CT rings with 11-23 and also 12-25 (mostly with the bike with 50/34). 52x13 gave me 105 inches, the same as 48x12 meaning that I have a bigger gear than I ever had in 46x11 & 50x12. I don't need a bigger gear (I pedal faster or coast). I don't know if I need any smaller, as I don't have larger than 25 because I like small gaps and have an obsession with keeping the 18 cog. I'm a compact fan.

[sawyer]

I have 52/36, 50/36, and 50/34, and tbh don't notice a huge amount of difference, perhaps because I don't shift the front much

On advantage of the 50 is that you can leave in the 50 a bit more than in the 52 for short sharp hills

[fromtrektocolnago]

What I miss about 52-39 is the small ring would feel faster and stiffer to me and I find myself in the big ring a lot more. Everything is a compromise. I would have had issues climb Alpe De Huez in a standard set-up. Gonna be doing a 14% climb 2 mile climb that peaks at 24% next week and a compact would've come in handy but i'm not planning on switching my semi-compact set-up for one ride.

[alcatraz]

I have 52/36, 50/36, and 50/34, and tbh don't notice a huge amount of difference, perhaps because I don't shift the front much

On advantage of the 50 is that you can leave in the 50 a bit more than in the 52 for short sharp hills

The difference is only 2t thats why. 2t makes a small percentual difference on chainrings because they are quite big.

Comparing for example cogs 12t and 11t on the cassette is percentually a much larger difference.

/a

[Marin]

The difference is only 2t thats why. 2t makes a small percentual difference on chainrings because they are quite big.

Comparing for example cogs 12t and 11t on the cassette is percentually a much larger difference.

/a

This is really hard to understand for most people.

50x11 is already MUCH faster than 53x13 - which Merckx won 5 Tours on.

[Hexsense]

The difference is only 2t thats why. 2t makes a small percentual difference on chainrings because they are quite big.

Comparing for example cogs 12t and 11t on the cassette is percentually a much larger difference.

/a

This is really hard to understand for most people.

50x11 is already MUCH faster than 53x13 - which Merckx won 5 Tours on.

Exactly. 50x11 is already equavalent to 54.5x12. 50t vs 52t is 4% and 11t vs 12t is 9%.
That's what i have to tell myself every single time i'm thinking about going back to 52/36 when someone try to persuade me that there are some mechanical advantage to it and i'd be faster on 52 vs 50.

I'm a humming bird type of riders (compare to my local group). 3 hours ride with average heart rate of 178, max 204. My leg strength is limited and can easily busted by pushing too much torque. Yet i keep up with group with higher cadence. My cadence stay around 95 up to around 300 watts. But i can't push much harder with this same cadence. When i sprint or do hard effort, it's the cadence that goes up more than the gear. Sometime it reached (peak, not sustained, ofcourse, I'm not a pro) 135RPM in 50x13 or 50x14 when people claim they can't keep up with me (in the end of the ride sprint) because they run out of gear.... Yet they advise me to change to 52/36 already because it would suite me better as i'm too fast to ride compact...

Okay, i'd mate up with 52/36 fine. but then i'll sprint at 52x14 instead of 50x13 at 130+ RPM anyway. I don't think it'll make me faster.

EDIT: make it more clear that those numbers are only for peak in the sprint. not sustained.

[shimmeD]

I can only assume that people (and pros) are just not pedaling as fast as Merckx - 53x11 vs 53x13.
It's a fair enough argument that we can't pedal as fast as the pros so we have a bigger gear and we're not as strong as the pros so we have smaller gears.
If I use Merckx as my yardstick my ideal setup is 48/34 with 12-25, give or take 1 tooth in the chainrings. I'd rather have the small gaps and the easier gears so I'll just coast if I run out of gears. That's my compromise; you choose yours.