Commuting - Nexus SG-8R25 vs. Sturmey Archer XRF8

which is the better internal hub 8-speed sytem?

I would say the nexus, but since the shimano alfine will soon be on the market I would wait for it.

I don't know anything about the Nexus; but I have the SA XRF8 on one of my bikes and it works great. I have only had this bike for a couple of weeks so no long term review from me. The gear spacing is really wide and gives me pleanty of choices. It shifts flawlessly (although I am pretty habitual and have to keep reminding myself to stop pedaling while shifting as I am used to shifting while pedaling; don't know how much difference this makes as when I forget it still shifts fine). My mechanic prefered it over the Nexus and he is a knowledgable mechanic; so thats all I can tell you.

Gear, is that the disc-braked version of that hub? You're the first person I've found who has actually used one, keep us posted on how it works. Is there noticeable drag? Noise? You said the ratios are pretty wide, isn't 1st gear direct-drive? What is your bike set up (frame, gearing, use?) Obviously I'm really curious, as I considered this hub but couldnt' find any real-life users out there.

The Nexus shifts more smoothly (and can be upshifted while pedaling forward) and has higher quality bearings and seals. The Sturmey-Archer has direct drive as its lowest gear, making it best suited for small-wheeled bikes, especially given the 22% jump at the top of the range. If you set up the SA 8-speed for a decent gear range on a bike with normal wheels, that top gear will probably be in the 130 inch range, which is pretty absurd for most people, even on downhills. On the other hand, the 22% jump at the bottom is great! The other gears are very evenly spaced. The jumps on the Nexus are a lot more irregular in general, but the big ones aren't at the top, which is what really sucks about the Sturmey-Archer, in my opinion. Another thing to consider: the spacing on the Sturmey-Archer hub can be adjusted from 118 to 135mm. This makes it much easier to retrofit an older bike with a new hub without the need to re-space the rear dropouts.

At this time (though this will soon change), the Sturmey is the only 8-speed hub that can take a disc rotor. Frankly, I think that this is basically a non-issue with internal gear hubs. The only good way to equip an internal-geared or other straight chainline bike with disc brakes is to use an eccentric BB. Otherwise, you would constantly be needing to adjust your disc brakes whenever you change your chain tension. Who wants that?

Also, the Nexus is about $40-$50 more expensive than the Sturmey-Archer 8-speed.

They're both good hubs, though the new S-A hasn't been available for long. They each have different strengths and weaknesses, and your choice of hub should really be dictated by which will better fulfill your needs than any concern about which one is "better." They're both high-quality hubs, both companies have a reputation for rugged, reliable equipment, they both have similar gear ranges and features. Either way, you really can't lose.

The Nexus shifts more smoothly (and can be upshifted while pedaling forward) and has higher quality bearings and seals. The Sturmey-Archer has direct drive as its lowest gear, making it best suited for small-wheeled bikes, especially given the 22% jump at the top of the range. If you set up the SA 8-speed for a decent gear range on a bike with normal wheels, that top gear will probably be in the 130 inch range, which is pretty absurd for most people, even on downhills. On the other hand, the 22% jump at the bottom is great! The other gears are very evenly spaced. The jumps on the Nexus are a lot more irregular in general, but the big ones aren't at the top, which is what really sucks about the Sturmey-Archer, in my opinion. Another thing to consider: the spacing on the Sturmey-Archer hub can be adjusted from 118 to 135mm. This makes it much easier to retrofit an older bike with a new hub without the need to re-space the rear dropouts.

At this time (though this will soon change), the Sturmey is the only 8-speed hub that can take a disc rotor. Frankly, I think that this is basically a non-issue with internal gear hubs. The only good way to equip an internal-geared or other straight chainline bike with disc brakes is to use an eccentric BB. Otherwise, you would constantly be needing to adjust your disc brakes whenever you change your chain tension. Who wants that?

Also, the Nexus is about $40-$50 more expensive than the Sturmey-Archer 8-speed.

They're both good hubs, though the new S-A hasn't been available for long. They each have different strengths and weaknesses, and your choice of hub should really be dictated by which will better fulfill your needs than any concern about which one is "better." They're both high-quality hubs, both companies have a reputation for rugged, reliable equipment, they both have similar gear ranges and features. Either way, you really can't lose.

Thanks! Have you ridden both? I wasn't aware of the non-shifting-while-pedaling sturmey issue. Sliding dropouts that have the disc tabs on them is also an option. I was initially attracted to the sturmey because of it's disc option, and the idea of using a very small chainring/cog combination appealed to me. Thanks for the clarification on the way the ratios are spread out on each, something I hadn't considered in detail.

Heh! Disclaimer: no, I have not ridden both. I have shifted the Nexus in the shop. All of this is information that you can easily glean from Sheldon Brown's fantastic website: www.sheldonbrown.com. I couldn't tell you which one is lighter, "more fun," feels smoother, etc. But everything else is just available information out there on the web.

Gear, is that the disc-braked version of that hub? You're the first person I've found who has actually used one, keep us posted on how it works. Is there noticeable drag? Noise? You said the ratios are pretty wide, isn't 1st gear direct-drive? What is your bike set up (frame, gearing, use?) Obviously I'm really curious, as I considered this hub but couldnt' find any real-life users out there.
No, its the version without brakes built in.
I had a bike that used to be a MBT (without suspension) that I converted to be a city bike. It was pretty good for this because it was sturdy and had a upright seating position. I wanted to replace this bike and also be able to take the bike on trips.
I chose to build my new city bike on a Montigue frame and use the internal hub as it would be less likly to suffer damage at the hands of bagage handlers while in transit.
The bike looks kind of wierd. It has no suspension but is definatly a MBT frame. The internal hub is mounted in vertical drop outs so it needs a chain tensioner. That makes it look like a single speed with a big rear hub with a cable coming out of it.
The hub shifts flawlessly. As I said the spacing is wide and I have a small chainring (one). Its like I had two (normal sized) chainrings and 9 gears and someone eliminated most of the gear choices leaving me with 8 spread from the highest to the lowest. Most of the gears make no noise at all, some have a light clicking sound (like pedaling backwards but less clicks and quieter). The first gear is direct drive as you thought, but it isn't noticable to me. I like the grip shifter but am not into looking at a shifter when I shift so I still go the wrong way from time to time and I still forget to stop pedaling when shifting from time to time. There must be some drag from the hub but I can't figure out how much is from the hub and how much is from the wide tires (I don't usually ride on the road with tires this wide); overall there isn't much resistance.

Hi Gear,

I have an SA-8. However, I am finding that 6th gear is quite sensitive to cable tension; i.e., the arrow being between the two lines.

Do you have this experience?

-G

I cracked an S-A8 on my town bike (xtracycle with electric assist) it was also one without a brake. I put it through more than it was intended to handle and basically road it to destruction. Had I had it on my commuter I think it would have held up for years.

I always thought the S-A shifter was a little clunky, but the hub always shifted smoothly. Compared to the SRAM hubs I've ridden, I prefer the SRAM shifters, but the SRAM hubs would give me trouble. I've had 2 SRAM hubs, and both would occasionally slip its gear (one could not hold its top gear, ever, on any incline), the Sturmey-Archer never slipped.

I've got a Rohloff on my commuter and it behaves like one would expect, it just feels nice. But at 1/4 it's price the NuVinci I now have on my town bike is damned impressive. The NuVinci is large and heavy, but man is it smooth. The shifter is second only the the Rohloff's too, just turn it and there you are, no clicks, no pressure to fight, it's nice. Quiet too, no click-clack when you coast, like a clutchless hub.

I cracked an S-A8 on my town bike (xtracycle with electric assist) it was also one without a brake. I put it through more than it was intended to handle and basically road it to destruction. Had I had it on my commuter I think it would have held up for years.

I always thought the S-A shifter was a little clunky, but the hub always shifted smoothly. Compared to the SRAM hubs I've ridden, I prefer the SRAM shifters, but the SRAM hubs would give me trouble. I've had 2 SRAM hubs, and both would occasionally slip its gear (one could not hold its top gear, ever, on any incline), the Sturmey-Archer never slipped.

I've got a Rohloff on my commuter and it behaves like one would expect, it just feels nice. But at 1/4 it's price the NuVinci I now have on my town bike is damned impressive. The NuVinci is large and heavy, but man is it smooth. The shifter is second only the the Rohloff's too, just turn it and there you are, no clicks, no pressure to fight, it's nice. Quiet too, no click-clack when you coast, like a clutchless hub.

So you had no issues with 6th gear being particularly sensitive to adjustment?

Not really, at least I don't think so. Every so often I would notice that it needed adjustment, about once in 200 or more miles. But I did not notice that any one specific gear would be more sensitive than another.

So you had no issues with 6th gear being particularly sensitive to adjustment?

I can't say I've had this issue on my bike, but it might be because my bike is way overgeared and I rarely touch 6th gear. I'm talking about the Downtube VIIIH.

I can't say I've had this issue on my bike, but it might be because my bike is way overgeared and I rarely touch 6th gear. I'm talking about the Downtube VIIIH.

That would make sense given the 20" versus the 16" wheel. Moreover, I swapped the 48T chainring for a 44T chainring to target 5th gear as my standard gear for the flat portion of the commute. So I end up switching to 6th on a regular ride quite a bit.

I did not bike commute today. But I will do so tomorrow. Hopefully, 6th gear begins to calm down after a few miles.

-G