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I really like the idea of ("compact") longtail cargo bikes, i.e. bikes with a regular frame shape but with an extra-large and sturdy rack for transporting medium-sized loads and persons/kids. Personally, I'd prefer one without electric assist. There don't appear to be many bikes to choose from in this category, I found the ones from Yuba, Xtracycle and Surly. All of these use a classic derailleur-based setup. I think that for such a bike, an internal-gear hub would be much more practical:

  • In inner-city traffic with a lot of stop lights, slow riders in front of you, pedestrians crossing etc., being able to shift quickly, possibly even under load, would be very helpful
  • The chain could be partially or completely covered, preventing entangling the cargo or passenger's pants
  • Less maintenance
  • Possibility of using a belt drive, even less maintenance

Why are there no longtail cargo bikes with an internal-gear hub? The only reason I can think of is that the ball bearings inside existing IGH's simply can't transfer the weight from axle to wheel, and:

  • The added weight doesn't matter much for such a heavy bike
  • Even though more mechanical energy needs to be applied for accelerating a bike with a heavy load, the rider's strength is the same, so it doesn't have to transfer more force in any instant (just for a longer time to get to a given speed as a regular bike)
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    This doesn't bear directly on the question, but you may wish to consider changing "compact cargo bike" to "longtail cargo bike" in the title and text. It looks like you're using "compact" to distinguish between this style of bike and something like a bakfiets, but "compact" is also used (e.g., by Yuba) to designate a cargo bike with an extended rear geometry that is not as big as a full-size longtail (and all of the bikes you linked to are full-size longtails). – RLH Apr 26 at 15:26
  • Thanks for the hint. "Longtail" is also a much better search term. – Erlkoenig Apr 26 at 15:37
  • You're welcome. I'd probably drop the "compact" entirely, since two out of the three bikes you link to are the full-size models produced by companies that also make compact longtails (and the third is a full-size from a company that doesn't make a compact model). – RLH Apr 26 at 16:02
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I suspect the main reason is cost - internally geared hubs are more expensive than derailleur setups.

Torque capacity may also be a factor. You are wrong about the force the hub has to withstand being only dependant on the rider. The torque on the hub is determined by the gearing ratio and crank arm length as well as the force the rider can apply.

A heavy bike will require a lower gear ratio between the chainring and sprocket to lower the overall gear ratio range. A lower gear ratio means more torque on the hub input for a given force applied to the pedals.

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  • Oh, I didn't think of that... Has noone thought about making an extra-sturdy IGH? Thanks! – Erlkoenig Apr 26 at 15:39
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    @Erlkoenig More weight + higher cost + low demand = doesn't get built – Argenti Apparatus Apr 26 at 15:41
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    Yes. Rohloff is approved for tandem use so it should be good for cargo bikes too. They are rather expensive, but there are enough buyers in that niche that they get built. – ojs Apr 26 at 16:03
  • I don't get the cost argument, surely it could be done as an optional upgrade? For every person prepared to spend $3000 on a cargo bike there's probably another one who would spend $3500. Big Easy costs $5000 so it's not a budget demographic – Swifty Apr 26 at 18:26
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    People do upgrade them aftermarket. It’s likely that the overhead cost to make them a production option is not worth’s he extra sales, and that consumers willing to pay for the IGH are also willing to eat the cost of the stock drivetrain, or go straight for a frame-up build. The Big Dummy, at least, has frame features to support a Rohloff torque arm. – RLH Apr 29 at 4:13
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In addition to the arguments presented so far:

I would think that the heavier the bike, the more gear ratios one would want, especially in a hilly area like where I live. If I were the one considering buying the bike, then I'd want to see a really low gear for getting a heavy load started uphill, a good selection of middle gears, and lots of gears in between. (Having lots of high gears for top speed downhill wouldn't be important to me.) In general I'd be thinking the more gear ratios, the better.

I think I've only seen 3-speed and 5-speed internal gear hubs, but Sheldon Brown's site says there are 11 and 14 speed internal gear hubs, and even continuously-variable ones. But, continuously-variable IGHs aside, the derailleur-equipped bike will generally have more "speeds". (Sheldon's site agrees.)

An internal-gear hub would be nice for keeping people's clothes clean and being able to shift while stopped, but if the IGH had less ratios than the derailleur-geared bike, then I'd pick the derailleur-gear bike.

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  • Would the downvoter care to explain? – rclocher3 Aug 6 at 14:19

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