Shimano Alfine SG-S700 11 speed short ride and information

[MitchJi]

Hi,

Sounds pretty good. Several online stores have it listed (out of stock - Harris expects 11-12-2010), priced about $550-$650.

32h and 36h disc brake versions.

Any educated guesses on strength compared to their 8 speed?

http://road.cc/content/news/13981-shimano-alfine-11-speed-hub-car-park-test

We reported earlier today that Shimano were going to show us their new Alfine 11 speed hub, and they did. It turns out that most of what was reported pre-launch was pretty much spot on, but for the sake of completeness we'll go from the top with the launch, and our impressions on a first short ride.

First up, it's an 11 speed system. The shifts are constant percentage increases, 17-18% per ratio, and that means that the total range is 409%, up from 8spd Alfine's 307% but not quite on a par with the 526% Rohloff Speedhub. However, the extended range brings it much more into both touring and MTB territory. Alfine 8 already has a small but committed following in hardtail MTB circles, and the 11 speed version is likely to be well received there. Alfine hasn't really been specced as a touring option before. If you're loaded up then you need a big gear range, and the new 11 speed hub gives you that.

Secondly, it's a completely redesigned hub from inside to out. Shimano haven't just shoehorned three extra ratios into the existing unit, they've worked from the ground up to make a better one. The 11 speed hub uses a helical system running in an oil bath, which should mean much lower maintenance – Shimano told us that we could expect the service interval to be lengthened by a factor of three. What's more, there's no stripping and greasing: the hub has an oil port, and changing the oil is simply a case of sucking the old stuff out with a syringe of some description, and pumping some new oil in with the same tool. In terms of longevity and basic servicing it should be a massive improvement over the Alfine 8, which means that it's likely to be a viable option for touring as well as town riding.

Redesigned shifter has two way release and two-ratio sweep

The hub internals use tapered sprockets which give a much smoother and lighter shift than the eight speed. What's more, the internals have been designed so that the action of the rapidfire shifter mimics that of its derailleur siblings: thumbshift for a lower gear, trigger release for a higher gear. As someone pointed out on our teaser article, arranging the hub like that would mean that a broken shifter or snapped cable would leave you in the top cog, and that is the case. It's a pretty unlikely case though, especially when you consider that the tension in the cable is pretty low. You might want to pack a zip tie so that if your luck did run out, you could fix the cable in an easier cog. The Rapidfire shifter will shift up two ratios at a time, and has two-way release too so you can push to shift down the block. If there was a block.

Alfine and Nexus sprockets are compatible, single cable operation

So what's it like to ride? well, we put in maybe a mile or two of riding so it's far too early to talk about durability and efficiency and things like that, but in terms of ride feel, make no mistake: this is a massive step up from the Alfine 8 hub. In fact it's such a different beast that one of the most-asked questions at the launch was why Shimano has chosen to associate it with the eight-speed hub by giving it the same name; we didn't really get a good answer to that one, but we did get an honest one: "we're better at engineering than marketing", was one reply!

Step over the bike and push off and there's no indication that you're running a hub gear. It isn't whirry or clicky, it doesn't feel vague like the eight speed version can in some ratios. The shifting is fast and precise, much more like a derailleur Rapidfire than the eight speed hub. It took us a while to get used to the fact that it was reversed from the other hub, but it'll make sense in the long run.

Once you're out on the road the hub spins up to speed well – even with three extra gears, it's going to be about 100g lighter than the eight speed at about 1590g, that's 120g lighter than a Speedhub – and the range of gears is really impressive, not least because there didn't seem to be a dud one in the pack. Presumably there's a direct drive ratio in there but we couldn't from the test ride tell you where it was, the gear feel is pretty much exactly the same across the range. There were a couple of changes that weren't immediate, but the hub didn't slip, just whirred a bit until it skipped to the next ratio.

First impressions are of a very slick, very quiet, very well designed system. The Shimano boys were pretty excited about it and we can see why now. The obvious comparison is with a Rohloff Speedhub: you don't get quite the range or the level of engineering with the Alfine but it's going to be a lot cheaper...

Shimano video here ("we expect it to be as popular if not more popular for Mountain Biking"):
[youtube]7wuXoD9db04[/youtube]

Six page thread here with some interesting information:
http://forums.mtbr.com/showthread.php?p=6589526
http://forums.mtbr.com/showthread.php?t=590178&page=5

You might have not noticed, but Shimano requires a chaingring to sprocket ratio of approx. 1.9 for the Alfine 11 in its tech documents [there is no mention of a (similar) constraint for the 8 speed version]. The same constraint for the Rohloff is 2.35 for normal use and 2.50 for heavy riders and/or heavy loading...

Service and Installation Instructions pdf:
http://techdocs.shimano.com/media/t...0A/SI-37R0A-002-ENG_v1_m56577569830728103.pdf

Excellent ratios for pedal assist with an ebike?

2. With the 1.9 input ratio, the new hub, when compared with the Alfine 8, adds gear ratios that almost none of its potential users needs.

Let's look at speeds achieved at specific gears, assuming 28/29 inch wheel size and 70 rpm cadence, the one most frequently observed.

Alfine 8
1. 9,6 kph ~= 6 mph
2. 11,7 kph ~= 7,3 mph
3. 13,6 kph ~= 8,5 mph
4. 15,4 kph ~= 9,7 mph
5. 18,2 kph ~= 11,3 mph
6. 22,2 kph ~= 13,9 mph
7. 25,8 kph ~= 16,1 mph
8. 29,3 kph ~= 18,3 mph

Almost perfect range and enclosing top end, considering capabilities of average bikers, qualifying as commuters and recreational cyclists. 1st gear is enough to climb bike ramps or some typical slopes to be found in urban or suburban area.

And the Alfine 11?
1. 9,6 kph ~= 6 mph
2. 12,4 kph ~= 7,7 mph
3. 14 kph ~= 8,7 mph
4. 15,9 kph ~= 10 mph
5. 18,1 kph ~= 11,3 mph
6. 20,6 kph ~= 12,9 mph
7. 23,5 kph ~= 14,7 mph
8. 26,5 kph ~= 16,6 mph
9. 30,3 kph ~= 18,9 mph
10. 34,3 kph ~= 21,4 mph
11. 39,1 kph ~= 24,4 mph

Who needs 40 kph? Who can hold this sort of speed over a longer period? Same with 35 kph.

Interesting (to me) Rohloff post in the Alfine 11 speed thread:

No. Rohloffs last because many years ago their inventor, Bernhard Rohoff, asked himself a question - what can possibly cause failures of an internal gear hub, answered it and came up with mitigation means.

So let's try to follow Bernhard's thoughts... what might possibly lead to the destruction of an internal gear hub and how to address it?

1. Intruding sand, dirt, water or moisture: so seal the hub as good as you can.

2. High torque loads (in form of spikes as human beings do not produce continuous torque): so divide and conquer then. Two first set of planetary gears in the Speedhub transfer low, safe torques due to required high input ratio. Only the third reducing one has to be particularly strong.

And you can see just that on the video done by climbercraig66:
[youtube]lS6kj8g5On8[/youtube]

At 5:57 sun gears of first two sets can be seen, they are fairly narrow and light. At 8:38 the sun gear of the third reducing set appears, and it's very wide to handle higher load. Additionally, by arranging the sets in this way, only one of them has to be heavy.

3. Cable misalignment causing non-precise shifting action: so make sure cable tension is no longer relevant in determining actuation driving the shift. Speedhubs are indexed internally so cable movement only triggers the shift, but does not drive it - the internally controlled actuation which is always the same, however, does.

 

[Green Machine]

I would be interested to know the strength of the alfine 11 as well.

 

[Whiplash]

I don't know, the Rohloff is the best right? It looks VERY fragile to me! I really doubt it would last behind a powerful R/C motor! I mean it is nice for its size, but I just don't see it handling 6-7HP unless I am totally off my guess.... Maybe the gears are made out of 300M steel or something...