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Discussion Starter · #1 · (Edited)
Why are the front rings for these systems not in the low 20s like a 3- or 2-by system? Edited to add: And why the 42 in back versus something smaller to pair with the smaller ring?

It seems like if they were, we could have more clearance with lighter and less expensive parts. Is it about selling new parts/systems? I don't think having 11 gears in the back constitutes an appreciable advantage. Honestly, 9 or 10 speeds seems like plenty for graduated steps.

What am I missing here?


I have XX1 on a bike and love the simplicity. My other bike is 2x10 XO type 2; would love to go 1x but have a hard time justifying a pricey drive that will supplant a basically killer clutched system. Ditching the FD/big ring and adding a guide seems like the right move. Some will question the low-ness of the range, but I do want some ridiculously low gears for bikepacking.

Ruminations very appreciated :)
 

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Because most people that ride bikes don't live in areas that require a 24x42 low gear.

And, it's a premium group set designed with various types of racing in mind. Most bike racers, regardless of discipline, are quite fit and would never need the gears you're proposing.


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ATM, there also seems to be a lower limit for the big/alternating teeth pattern that plays well with the chain. Even at 28t, some people complain of grinding.

If you can get by with the gearing of your DIY 1x10, awesome.
 

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Discussion Starter · #4 ·
Because most people that ride bikes don't live in areas that require a 24x42 low gear.

And, it's a premium group set designed with various types of racing in mind. Most bike racers, regardless of discipline, are quite fit and would never need the gears you're proposing.
Interesting, Duke, but aside from my own spinning tendencies and too-low gears for a loaded bike, wouldn't racers benefit from smaller and lighter cogs/chainrings? I'm not proposing 24x42; more like a 22x34 granny. My point is, the same 28-34 x 42 ratio range could be achieved with smaller and lighter parts that, logically, would be less costly to produce.

Does wear or something else become an issue with smaller cogs/rings?
 

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Use Sheldon's gear calculator and plot it out like I did. A typical sram 1x11 covers almost the exact range of a typical 2x10, it is pretty amazing and answers why it is taking off like wild fire.
 

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1: smaller cogs/rings would wear faster, i.e., 32/16 is the same ratio as a 22/11, but the latter would wear faster.
2: it's not really about the low gear, so much as the range. There is a limit to how small you can make a cog; Sram, in some of the early interviews referred to it as the polygon problem: a chain laying on a cog isn't describing a circle, it's a polygon with the pins as sides. The fewer sides a polygon has, the more the difference between the corner and side radii, so for example if you were to make a 4t cog, you'd be trying to pedal a square (the effective gear ratio changes through rotation). Sram claimed that 10 was the low limit before they saw undesirable effects. 10 might not really be the limit, but I'm sure it's not a lower; even if they went to a smaller-pitch chain, the cog would still have to fit around a 12mm axle.
3: I doubt it would cost less to produce in any event. The cost of these parts isn't driven by weights or volumes of materials, rather by complexity (and thus machine time), and I've never seen a part get less complex as it got smaller.
 

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You can't rule out frame designs as well. A lot high end frames these days are designed around a range of chainring sizes in mind that have an effect on how efficiently the bike pedals. The are often in the 30-36 tooth range.
 

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Interesting, Duke, but aside from my own spinning tendencies and too-low gears for a loaded bike, wouldn't racers benefit from smaller and lighter cogs/chainrings? I'm not proposing 24x42; more like a 22x34 granny. My point is, the same 28-34 x 42 ratio range could be achieved with smaller and lighter parts that, logically, would be less costly to produce.

Does wear or something else become an issue with smaller cogs/rings?
You're completely ignoring the high gear inch part of the range.

People would have to spin an uncomfortably high cadence on any flat or slight downhill sections if gearing changed as you've suggested.


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Have you ever seen a cassette with the 3 smallest rings worn out? Probably never.

Have you seen a cassette with the 3 largest rings worn out? All the time.

Maybe people think they are stronger than they really are.
 

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Smaller gears increase wear

But more importantly, you can't easily go smaller than 10 or 11 in the rear. So of you want any range you have to go bigger.
 

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2 reasons, both mentioned

1 many suspension systems are designed around efficiency at a certain size front ring - usually 32
2 you can't go smaller, so if you want to increase total range, you either do it at the front rings or on the big end of the cassette
 

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Have you ever seen a cassette with the 3 smallest rings worn out? Probably never.

Have you seen a cassette with the 3 largest rings worn out? All the time.

Maybe people think they are stronger than they really are.
Depends where you live. When I lived on the relative flats I have seen dozens of 11-34 cassettes with three smallest cogs worn out. Of course me, being a smart person I am ;), used a road cassette there ( 12-26 with 44-34 rings ), but most people were stubborn and used a regular wide ratio cassettes.

On the other hand, the group I ride with now wears out their low gears mostly since climbing is the most common type of riding.

EDIT:

As for OPs question. People use 1x11 because it is simple and good-enough for most of their riding. 420% range is sufficient for pretty much all trails, except hardcore climbs and road riding. At the same time 1x systems are efortless in use. You need lower gear-click, you need higher gear-click. If you are at the end of range, either coast or walk.

I found that if you can ride 90% of conditions, then people are willing to compromise on the remaining 10%.
 

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Depends where you live. When I lived on the relative flats I have seen dozens of 11-34 cassettes with three smallest cogs worn out. Of course me, being a smart person I am ;), used a road cassette there ( 12-26 with 44-34 rings ), but most people were stubborn and used a regular wide ratio cassettes.

On the other hand, the group I ride with now wears out their low gears mostly since climbing is the most common type of riding.

EDIT:

As for OPs question. People use 1x11 because it is simple and good-enough for most of their riding. 420% range is sufficient for pretty much all trails, except hardcore climbs and road riding. At the same time 1x systems are efortless in use. You need lower gear-click, you need higher gear-click. If you are at the end of range, either coast or walk.

I found that if you can ride 90% of conditions, then people are willing to compromise on the remaining 10%.
Fair enough.

I'm a victim of my own experience being a NE rider. Most trails are tight and straight up or straight down.
 

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As for OPs question. People use 1x11 because it is simple and good-enough for most of their riding. 420% range is sufficient for pretty much all trails, except hardcore climbs and road riding. At the same time 1x systems are efortless in use. You need lower gear-click, you need higher gear-click. If you are at the end of range, either coast or walk.

I found that if you can ride 90% of conditions, then people are willing to compromise on the remaining 10%.
This sums it up pretty well. A 28T chainring on a 1x with 42T granny gear is the exact same ratio as a 24:36 out of a good 2x10 setup on the granny side, while only giving up about two of the highest gears. Moving to a 32T chainring loses that one granny gear (instead it's really close to a 24:32 on the granny) and only the top-most gear, in short losing a whole chainring up front means the loss of only two gears if a 32T chainring is used - depending which extreme gets used, only losing two gears is the better way to go.

In all honestly, with a 42T ring on the back as an option, having a chainring smaller than 28T is simply adding a granny gear that isn't typically needed, since anything I can't spin up at that ratio is something I'm probably going to have to walk up instead. That still yields a gear ratio equivalent to the big chainring in a 2x setup and the 8th or 9th gear on a standard 10x cassette, which for a 29er is simply plenty adequate - anything faster than a high-cadence 35mph is probably not worth the weight tradeoff if it's not used often.
 

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When I had 3x9, every cassette would die in the 7th and 8th (2nd/3rd smallest cog) as I wasn't strong enough to push the 44 large ring with only 32 or 34 at the back.
Now I have 2x this moves about a bit more as my big is now 40, and I stick in the large ring much more.
 

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Use Sheldon's gear calculator and plot it out like I did. A typical sram 1x11 covers almost the exact range of a typical 2x10, it is pretty amazing and answers why it is taking off like wild fire.
Oh goodness, again with the misinformation. I ride 1x, but to claim that a single 1042 cassette has almost the same range of a dual is just silly, especially now that 1140 cassettes and 1142 cassettes are available. No matter what you do a single is at least 2 gears shy of a race ready 30-38 dual with 1140, more if you use 1142, and even more if you separate your chain rings for trail use, e.g. 26-40. Put in the picture the new top swing front derailleur, that let you access the whole cassette from both chain rings, and a dual start to look VERY appealing.

1x is and will remain a compromise, that is only good in certain areas and terrains, and as far as the 10 cog is concerned I bet it will disappear in a few years because of the non standard hub.
 

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In all honestly, with a 42T ring on the back as an option, having a chainring smaller than 28T is simply adding a granny gear that isn't typically needed, since anything I can't spin up at that ratio is something I'm probably going to have to walk up instead. That still yields a gear ratio equivalent to the big chainring in a 2x setup and the 8th or 9th gear on a standard 10x cassette, which for a 29er is simply plenty adequate - anything faster than a high-cadence 35mph is probably not worth the weight tradeoff if it's not used often.

I ride a 26er, with 22/32/44 and 11-34 9spd. The 28/10-42 is good, but still does not offer the range of my 3x9

Bottom end you are right 22/34 granny is something I use from time to time and I am really happy to have it when I do. ratio is .65 28/42 is a .67 and to me that is a close enough to the same. Where things go south however is on the top end. 44/11 os 4.0 ratio, but 28/10 is 2.8. My my 32/11 is a 2.9 and equivalent so for my on pure range a 28x10-42 is the same range as 22/32x 11-34. On the terrain I ride I may not use my 44 chain ring much, but I do use it and often on same rides as when I use that 22/34. Steep climbs often lead to fast descents. In a week I will be doing the whiskey 50 and I know I will be using 22/34 at times and using the 44/11 at times on the same ride.

I have not even brought up the intermediate ratios. With 22 small ring and 11-34 I have a 30 ratio and 26 which I tend to use a lot. I guess for me I like have versatility and with a triple I get a greater range that the new fangled 1x11 and have close spacing. I don't have to choose a low end bias with a small chain ring or high end bias with big chain ring. I get both because I am brining 3 chain rings. One for steep climbs, one for gentle climbs, flats, and descents and one for top speed (ie 17-25mph and wanting to pedal)
 

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I still haven't seen anybody really usefully make the entire range of a 3x setup work - my oversized self I can make us of the bottom 28 gears on my 3x setup (that same SRAM/Truvative 22/33/44 Crank; 11-36 cassette), but I completely agree that the intermediate gearing availability is still an improvement. The intermediate ratios have surprising amount of overlap, especially with a 3x (still only like 16 unique ratios), but it's the outer 4 ratios that I wouldn't consider parting with. A good double can cover that same ratio comfortably, or at least only drop one gear at either extreme at lower weight and simplicity; in 33:11 I'm still doing 25mph pedaling and unless I'm going down a greater than 4% grade that's plenty. I can throw it on my big ring and put in 600W pedaling efforts, but that only buys me another 5mph and a deafening wind; I'd rather have a 2x10, run a bash guard, and be able to use a bit less chain since I ride like enough of a clown to actually knock it off the crank.
 
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