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I recently converted my bicycle from a derailleur setup to an internally geared hub. During the conversion, I also replaced the previous crankset (with three chainrings) by a crankset having a single chainring. I am very happy with the result because I mostly ride in flat to slightly hilly terrain where the gear transmission ratios provided by the hub suffice. I especially like the perfect chainline on the bike.

However, I might have to use the bike to climb steeper hills from time to time. For this purpose, a crankset with two chainrings might be interesting. Because with the current chainline the chainring is already very close to the frame, there is no way of adding an extra, smaller chainring to the left of the chainring I would use 99 % of the time while keeping the perfect chainline for this most important chainring.

However, I have my old, now unused crankset to play around with. I wondered if it would be possible to mount a smaller chainring to the right of a bigger chainring. The answer is: Yes, it is possible, and to me it looks like it could work (see photo below). This way, I would have a rather bad chainline with the smaller chainring, but I would use it only in rare cases.

The question is: Is there a reason that the chainring size in all bicycles I have seen so far increases from left to right or can this be inverted without difficulties? Has anybody here tried to change the chainring order and can tell if it works?

Here is the photo of my old crankset with swapped chainrings: enter image description here

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    How would you switch between the two? Modern front derailleurs are designed to move to larger rings on the outside. – Andrew Dec 7 '19 at 22:09
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    Yeah, the derailer wouldn't work. But you could shift manually (stop and move the chain by hand). This used to be a "thing", about 60 years back. – Daniel R Hicks Dec 7 '19 at 22:34
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    Remember that, in addition to the problem with the front derailleur, you'll still need to maintain chain tension, using something like…a rear derailleur. – Adam Rice Dec 8 '19 at 1:41
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    @Adam Rice: True. To keep up chain tension during the lifetime of the chain I have to use a chain tensioner anyway because I have vertical dropouts (like this one: bike.shimano.com/en-EU/product/component/alfine-s7000s700/…). So this would not be a problem, and I have one with a spring which is especially made for the combination of an internally geared hub and a front derailleur. – Snijderfrey Dec 8 '19 at 9:08
  • @Andrew: Good point with the front derailleur. Is this theoretical knowledge or have you tried it? When I find the time, I might just give it a try with an old bike anyway, even if it should be hopeless. – Snijderfrey Dec 8 '19 at 9:20
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I've done the chain-setting by hand for a couple days when I was waiting for a replacement front mech to arrive. It worked, but without a FD cage the chain could bounce around and fall off at bumps, like coasting through gravel.

Also, setting the chain while riding was awful-risky because you're bent right down to reach your chain. It gets old fast, and every time risks catching a finger or missing something going on in the traffic. Plus you get dirty fingers/gloves.

You already have the solution of a front derailleur. The only perceived advantage is getting a straighter chainline in the big ring. So the fix there is to use a triple crankset, and set your big ring in the middle position, leave the outside position empty, and put a middle ring on the innermost position.

The only question here will be finding a FD that moves suitably - you may need to mount it higher up the seat tube than normal, and possibly require a friction shifter not an indexed shifter to get the chain sitting right.


I have a shimano alfine 11 with a 22/34/44 triple, and I have never needed the granny ring even when going up a 15% gradient. The granny 22 tooth simply didn't give me the 4~5 km/h minimum speed I needed to keep balanced, so it was necessary to apply power in 34:gear1 or 25 gear inches, rather than down in the sub-20 gear inches ranges.

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Since the front derailleur moves up when shifting out and the outer ring is smaller, the chain will most likely fall off. And shifting inwards will wear the bigger chainring since it is not made for changing gears from the bottom right. The bigger chainring has small pins that will make changing gears smoother but the other side doesn't, so you're basically slowly but surely shift gears and wearing the chain more.

I'm not a pro at these so I might look like I don't know what I'm talking about but those are the things I think might happen if the chaining is like that.

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Chainline could be an issue. Cross-chaining, i.e. big ring and big cog or small-small, is bad because it increases chain wear and drivetrain friction.

With the large chainring on the outside as it normally is, it’s positioned to have good chainline with the middle and smaller cogs, i.e. your highest gears. If the big ring was on the inside, then when you want your hardest gear, you are cross-chained. The same issue exists when you want your smallest gears.

Also, if you put the small ring outboard and you want your lowest gear, it’s possible the chain will rub on the big ring. I don’t know the angles involved, but it could rub much worse than running the rub you’d get running big-big or small-small.

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    Nice explanation and true for derailleur gears, as long as inverting the sprocket cluster is out of question. For an internally geared hub, you usually have only one sprocket and therefore not the same reasoning applies. – Snijderfrey Dec 8 '19 at 18:12

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