Alfine 8

I'm pretty into gear hubs, and I've ridden a lot of them, summer and winter, flat and hills.  Sometimes the market seems pretty static, and it feels like I know all the products.

Well, I had a bike that needed a hub that worked with a disc brake.  The only reasonably-priced reasonably-speced option is basically a Shimano 8-speed, so I could buy what would then be my 5th example of Nexus 8.  I have one with the more efficient bearings (model SG-C6010-8R) which is pleasant, so I wanted more of that, but of course Shimano is playing a game.  You can get those bearings in a Nexus 8, but only for a roller brake (or rim brake) or with electric shifting.  The disc-compatible cable-shifting version (SG-C6001-8D) has the regular bearings, and thats it.  Then they have another offering, the reason Nexus 8 is missing an efficient disc model: the Alfine 8.  Same ratios, but packaged in a shinier can, and different shifter.  Same guts though, I figured.  Costs a bit extra of course.
 

So after much thinking, I got one of those (SG-S7001-8 hub, SM-S7000-8 parts, SL-S7000-8 shifter, CT-S500 tensioner).  It is not merely a repackaged Nexus 8.

If I didn't know the backstory of the Alfine 8, I would not have thought it was related to a Nexus 8.  Not even the Nexus 8 with good bearings can measure up.  Of course it has the same 8 ratios, and you can still kind of feel an extra mechanical engagement going between 4th and 5th (basically a high-range low-range change).  The trigger shifter changes how one interacts with the hub (vs twist), but shifting in general is just better.  The gears themselves are just better.  It is really hard to tell the difference in efficiency or smoothness between 4th (the worst) and 5th (the best) even though I know perfectly well what is involved in generating those ratios.  (Maybe on a road bike I could feel something, but this build is a fatbike.)  The shift quality is also as good as it gets.  For comparison, consider a derailleur: upshifting to a faster/harder gear means dropping to a smaller cog, an easy lovely snappy operation.  The experience of downshifting on a Alfine 8 is very similar if not superior: a nice crisp clunk exactly when you ask for it.  You could call that a tie, perhaps.  Going the other way: downshifting a derailleur is way worse than upshifting an Afline 8.  While the derailleur is trying to push around the chain, the hub does what you ask, when you ask for it, with no particular noise or feel.

It must be emphasized that you should not shift under power with any of Shimano's hubs, but soft-pedaling is perfect, and I can usually just shift quickly at the moment the crank arms are oriented vertically, essentially without interruption.  The hub acts fast, it seems like a physical impossibility for any derailleur to respond as quickly.  So while you are strongly advised to not shift a hub under significant load, you also don't have much reason to try.

The quality of the Alfine 8 shifting that I have experienced thus far is especially remarkable because Nexus 8 has had, in my 4 examples of it, an uninterrupted history of being touchy.  The newer models have better designs than the old ones, but they all have minor persistent shifting annoyances.  In the older hubs, its mostly problems around the 4th-5th transition.  For the newer hubs, its mostly problems holding 8th gear.

Another bit of shifting-related info is that Alfine 8 is a default-high hub, where as Nexus 8 is default-low.  In other words, Alfline 8 without a shift cable installed goes to 8th gear, while Nexus 8 goes to 1st gear.  This also means that shifting to a lower gear on Alfine 8 involves the shifter pulling cable, while the hub spring pulls it the other way when shifting to higher gears.  Likely this cable pulling is a big part of the excellent direct feel when downshifting.  I think its a good choice, because when a person starts downshifting on a hill, they want it to happen immediately.  The cable also passes above the hub, enabling some interesting cable routing, as shown in the picture at the top.  A cable routed as shown, on a MTB frame with sloping top tube, has no low point in which water might accumulate and freeze.

The Alfine 8 follows Nexus 8 by offering a 307% gearing range.  Meaning the highest gear is slightly over 3x as fast as the slowest gear.  This is pretty good for normal people on pavement in my experience, although it can be on the small side when there are big hills.  The bike on which I installed the Alfine 8 came with double chainrings up front.  I kept those double chainrings and the front derailleur unchanged.  By using the Alfine chain tensioner (which looks like a derailleur arm, but is not one) I can switch between the small and large rings just like anyone else (anyone who has such an old-school thing on their bike, anyway).  There is naturally no cross-chaining or similar concerns with the gear hub in the back, just a range of 8 gears and no worries.  This is kind of the cherry on top of the whole setup.  Most of the time I run the big ring, and the small one can be used for major uphills (especially in the winter).  Total range top-to-bottom is now 474%.

A limitation of this setup is that the hub is really not rated to be used at an input ratio approaching 1:1, they recommend about twice that (or half that, depending on your perspective).  So while the big ring is pretty much approved for anyone and anywhere, the small one should be used with a bit of caution.  The way 2nd, 3rd and 4th "gears" are generated is to re-use 6th, 7th and 8th with a reduction gear (which is 1st "gear" when used alone).  That sounds fine, but Shimano seems to place the reduction gear first, so if you run the small ring with 2nd, 3rd or 4th, you're basically running 6th, 7th or 8th with doubled-up small rings.  (If that was possible, or makes any sense.)  Its a lot of torque compared to using 6th/7th/8th natively.  Maybe if you jumped up and down on the pedals you'd replicate it.  Anyway, take care in 2nd/3rd/4th when using the small ring.  I used all the ratios with the small ring at various points during the winter, but also I didn't stand on the pedals.  I have read some say that there is some flex or squish in an Alfine hub, and I sometimes believed I could feel it when using the small ring.  The jury is still out.  I concentrated on smooth application of power and finding zen, and climbed everything that needed climbing.

The main selling point of double chainrings with an Alfine 8 is greater total range, but I also have some moderate uphills where I found the small ring to be worthwhile.  With 22t and 34t chainings, it works out that small-ring-5th is about the same place as big-ring-2nd, but its more efficient.  The 5th ratio is direct drive, whereas 2nd is both 1st and 6th at once (i.e. two gearing stages).  Using 6th and 7th on the small ring is also a bit advantageous, though less so.  It has to be a long hill at the right slope before its worth shuffling around the gears to do it, but I happen to have such a hill.

This being started as a blog on Niholas, I should say that this hub seems like it would be a great cargo bike/trike hub.  Everyone seems to go electric these days, and I don't have anything to say about combining this with a center motor, but those few who want to pedal themselves around should consider Alfine 8.  I would even recommend it over a Nexus 8 with the good bearings (SG-C6011-8R/8V or similar) if you're going with a rim brake.

Summary: Alfine 8 is an attainable masterpiece.