Hub gear range?

[PH]

But how often can you push a gear over 100" other than when the wind is behind you or it's downhill?
In those circumstances a few extra % isn't going to make much difference to effort or speed.
If anything, I find the gaps to large around the cruising gears, 10,11,12 but you soon get used to it.

[markbUK]

I'm currently using a Rohloff with 17 & 39, giving me a low of 17 and high of 88 gear inches, my other bike is running 11-34 and 22,32,42 and provides similar ratios, I've geared low to give my knees a chance, the option to drop gears on a hill using the Rohloff is a real bonus to me rather than pushing to hard .. I would agree that at times the gap on the Rohloff is a little large but it's OK for me

The Rohloff is running 700 x 32 and other bike is 26 x 2 .. Hope the PIC helps

Mark

[syklist]

But the point is, with all attempts to even out gear intervals on derailleurs you end up having to think even more about which combination of the two gear changers you have to use for the next change.

With a Rohloff you get the even spacing and you never have to think about gear changing, apart from twist one way to get a higher gear, twist the other way for a lower gear. No contest.

sure, but keeping track of which of three chainrings I am/should be in isn't such hard work,

It must be great to be a derailleur ninja, knowing, without thinking, at one with your gears, how to get to the next gear you (unexpectedly and suddenly) need. But for mere mortals such as myself, trust me, a three chain ring derailleur is a pain in the neck. Especially at the end of a long and tiring day in the saddle whilst looking for a turning to a camping spot in undulating terrain.

I don't own a Rohloff, and I've not ridden one for long enough to know if I would ever feel the same way about it; reports of the measured variations in gear efficiency are not consistent, any more than different people's ability to perceive it might be. But I have heard some owners at least complain about the noise in 1-7, so I suppose it is possible that I'd end up knowing which gear I'm in just from the noise etc.

The "Rohloff Noise" debate always interests me. When you consider the range of clunks, graunches, clicks and chain rattles that occur when changing gear with a (clean properly adjusted) rear derailleur it seems strange to me that anyone would prefer that to the whirring noise that a Rohloff makes in its lower gears.

Take your derailleur bike and go cycle touring in the rain on sandy gravel tracks and your derailleur system is going start making a lot more noise than my Rohloff ever will.

[syklist]

4. SRAM dualdrive, (and similar SA hub) offer a cassette + 3s hub in one package.

Not really a hub gear in the same sense as a Nexus 8 or Rohloff. It is a derailleur setup where the triple chain rings have been replaced by a three speed hub. The DualDrive still has the problem that you cannot change between gears on the cassette if you come to a standstill. You can shift from "3rd chain ring to 1st" whilst standing still which helps a bit but not as much as being able to shift from 8th to 1st on a Nexus hub.

[geocycle]

The "Rohloff Noise" debate always interests me. When you consider the range of clunks, graunches, clicks and chain rattles that occur when changing gear with a (clean properly adjusted) rear derailleur it seems strange to me that anyone would prefer that to the whirring noise that a Rohloff makes in its lower gears.

Take your derailleur bike and go cycle touring in the rain on sandy gravel tracks and your derailleur system is going start making a lot more noise than my Rohloff ever will.

I'm a massive rohloff fan, but the two things I'd like are for it to be a bit lighter and for it not to have the noise in gear 7. On the noise you are correct in that it is overall quieter than derailleurs but the noise is somehow more noticeable. Personally I don't have a problem but it is not as quiet as some other IHGs. Similarly the weight is not much greater than a touring derailleur system, but having it concentrated on the back hub is noticeable when lightly loaded. Overall, these issues are not important and the positives exceed the negatives for my uses.

[[XAP]Bob]

4. SRAM dualdrive, (and similar SA hub) offer a cassette + 3s hub in one package.

Not really a hub gear in the same sense as a Nexus 8 or Rohloff. It is a derailleur setup where the triple chain rings have been replaced by a three speed hub. The DualDrive still has the problem that you cannot change between gears on the cassette if you come to a standstill. You can shift from "3rd chain ring to 1st" whilst standing still which helps a bit but not as much as being able to shift from 8th to 1st on a Nexus hub.

And you can make that change without dodgy chainlines.

If only it had a neutral gear between 2 and 3 (like some other 3 speed hubs) then you could kick it into neutral, change whatever you want on the dedangler and then knock it back into direct drive. Assuming youre on three wheels of course

[Brucey]

It must be great to be a derailleur ninja, knowing, without thinking, at one with your gears, how to get to the next gear you (unexpectedly and suddenly) need....

If only I were such a thing! I use friction shifters on that bike and I can tell at a glance (or from feel) roughly what gear I'm in because of how the levers are oriented. And with the setup I have described 'roughly' is more than good enough; there are essentially only two 'sizes' of shift and there is only one shift (the one between the middle and inner chainring) of the second size. So, no, it isn't at all complicated, if it were, a bear of very little brain like myself would have jacked it in years ago.

Take your derailleur bike and go cycle touring in the rain on sandy gravel tracks and your derailleur system is going start making a lot more noise than my Rohloff ever will.

Well I dunno; I do quite a lot of IGH riding in which the chain gets dirty and an IGH chain can also be quite noisy in these conditions. The only system that isn't like this is a fully-enclosed chaincase + simple IGH; my bike that is like this is almost silent in terms of mechanical noise.

In second place comes my recumbent, which has a simple (and already very well used) IGH as a mid-drive, plus a 9s rear mech, with no additional guide pulleys required in the system (which uses almost x3 the 'normal' amount of chain BTW). The noise from the rear mech is (to my great joy) somehow obscured by my body and is anyway slight because I am using carefully chosen components. Everyone who has tried this machine has said the same thing, which is how wonderfully quiet the transmission is; by contrast other machines with the cranks two metres from the driven wheel always seem rather noisy, usually because of the idlers/guides required.

A general comment that I would make about IGHs of many kinds relates to the tooth forms. Straight cut gears are invariably slightly noisier than (say) helically cut gears but the latter have their own issues which include efficiency (which drops off alarmingly if there is the slightest error in the tooth form), cost of manufacture, and generated reaction loads.

To my knowledge the only IGH with helically cut gears is the Alfine 11 and that has just the one, which generates a troublesome axial thrust load that can cause premature wear and consequent hub failure. So it would appear that (for bicycles anyway) helically cut gears are probably not the answer. Every other cycle IGH (or gearbox with gears in) uses straight cut gears. If the gear teeth are made according to the proper involute tooth form, you can have low tooth count gears and the noise/efficiency is not too bad (e.g. Pinion gearbox etc).

But how close do epicyclic gears in typical IGHs come to this? According to what I have read elsewhere, seen for myself, and indeed felt, 'not close at all' is the usual answer. The tooth forms in Shimano, SRAM, and SA hubs are at best only the vaguest approximation to an involute form, and are mostly cut with (simpler, cheaper) flat tooth flanks which don't even have a particularly good finish. I've examined a sample Rohloff (a cutaway sample with a complete centre as supplied to some dealers) and the teeth didn't look very much better in form than in other IGHs to me.

Most IGHs seem to 'run in' and the most used gears can eventually run more smoothly than when they are new. [Incidentally this may explain the poor efficiency results some researchers have seen; they have often tested hubs that are basically 'new'.] Anytime you have teeth that are few in number on a pinion, that pinion is well-loaded, not often used, and connected into the gear train in such a way as it can transfer vibrations and/or noise into the rest of the system, you will have 'a bad gear' that is noticeably worse than the others.

I do not think I have ever ridden an IGH in which I didn't feel or hear something of the sort; for example I have a SA 5s hub which has done about 45000 miles and bottom gear is still noisy, but top gear is worse yet; both gears use the same sun pinion (but opposing tooth flanks) and even after all these miles it still isn't 'run in' yet. This is despite the fact that this model of hub has a drag spring in it that keeps a little load on this sun pinion all the time (as much as anything else to prevent rattles I think, but it should lap the parts together anyway) . If I examine the teeth the finish is now OK, but the shape is still (and probably always will be) too far away from the ideal. [BTW the planet pinions also mesh with a ring gear in most of the other gear ratios and this meshing is silent by comparison, so I am pretty sure it is the sun pinion which is bad rather than the planet pinions per se.]

So the 'gear 7 noise' in a Rohloff is probably a case in point; there is presumably a part of the gear train (with only a few teeth on the pinions) which is only loaded in that direction in gears 7 and 14; it isn't likely to get 'run in' through gear 14 use...(unless Mick uses it...? ) and this may be what often makes gear 7 particularly noisy by comparison with the other gears.

I've owned and used several different Nexus 7 and Nexus 8/Alfine hubs and they have all been different from one another, but none has been 100% quiet in all gears, even after (in some cases) extensive use. It seems to me that the only IGHs which routinely become almost silent are SA three-speeds, and then only after many years of hard work, and when they are filled with a fairly heavy lube. [BTW I think these have a fighting chance vs other IGHs simply because the gears inside an AW all have lots of teeth on them, relatively speaking.]

In bicycle transmissions, perfection is still a way off, I feel; it is just a question which kind of compromises you want to make; if it were a simple choice, we'd all be using the same thing already, right?

cheers

[Mick F]

But how often can you push a gear over 100" other than when the wind is behind you or it's downhill?

I use it LOTS of times, in fact I can go for mile after mile after mile in top gear. Also, I can go slow using it on the flat. Maybe round town, maybe in traffic. I can start off in it on the flat. It's a "gentle" gear, you just turn the pedals gently and firmly without rushing or trying to accelerate too hard.

Often, I wish I had a higher one. My big ring is 53t, and I wonder about fitting a 54t but as it's Campag Chorus, the cost would be astronomical. I can't buy another make due to the holes position and profile as one bolt goes into the crank.

Other option is to change my cassette and fit an 11t, but that would be too high, even for me. 127" or thereabouts.
Maybe instead fit a 52t big ring (readily available as an option for Chorus) and coupled with an 11t would give me 125".
I like my 12-30 10sp cassette, and they don't do a 11-30, so I'd have to get some sort of custom one.

Any major changes to my gearing would see me fitting "another make" hub and cassette and reverting to DT shifters. Failing that ......................... it's a new bike!

[syklist]

It must be great to be a derailleur ninja, knowing, without thinking, at one with your gears, how to get to the next gear you (unexpectedly and suddenly) need....

If only I were such a thing! I use friction shifters on that bike and I can tell at a glance (or from feel) roughly what gear I'm in because of how the levers are oriented. And with the setup I have described 'roughly' is more than good enough; there are essentially only two 'sizes' of shift and there is only one shift (the one between the middle and inner chainring) of the second size. So, no, it isn't at all complicated, if it were, a bear of very little brain like myself would have jacked it in years ago.

You fall into the Intiate Derailleur Ninja class then. It IS complicated. You have to take your eyes off the road to check two controls to know roughly what gear you are in. You have just accepted this complication as normal.

With a Rohloff you NEVER need to know which gear you are in only which way you need to turn the twist grip. Except maybe when starting from standstill but even then not really necessary. If you realise you are in too high a gear when starting on the flat then you are a split second away from a much lower gear. My routine for starting on steep hills is to select 1st by winding the twist grip all the way in the correct direction and then go the other direction two clicks which selects third gear. Stand on the pedal, bum on the saddle and change back down to first after the first down stroke is complete.

I find that the whirring noise in the low gears is useful as it tells you when you have changed into the low range without having to take your eyes off the road and look at the gear changer.

[Elizabethsdad]

Haven't read all the posts to see if this has been mentioned. If you have the money for it, a Rohloff combined with a Schlumpf drive will give you 28 speeds over a vey wide range - haven't done the calculations. A slightly cheaper option is the Alfine 11 combined with the new 3sp Efneo crank gear. The Efneo has yet to be fully released on the market but can be pre-ordered. I have decided to try one for my Bakfiets long John to increase the range of the N360 hub gear - the last e-mail from Efneo said the expected to ship in November. A while back I had a Carera Subway 8 with the Alfine 8sp hub and that coped with everything I ever had to do. If you can get something like that second hand it might be worth it to see how you get on - and it will then be there as a spare n+1 bike.

[syklist]

Re Alfine 11, have the reliability/durability problems been solved? The last time I checked it looked like the Alfine 11 was still not as robust as a Nexus/Alfine 8.

[Brucey]

It must be great to be a derailleur ninja, knowing, without thinking, at one with your gears, how to get to the next gear you (unexpectedly and suddenly) need....

If only I were such a thing! I use friction shifters on that bike and I can tell at a glance (or from feel) roughly what gear I'm in because of how the levers are oriented. And with the setup I have described 'roughly' is more than good enough; there are essentially only two 'sizes' of shift and there is only one shift (the one between the middle and inner chainring) of the second size. So, no, it isn't at all complicated, if it were, a bear of very little brain like myself would have jacked it in years ago.

You fall into the Intiate Derailleur Ninja class then. It IS complicated. You have to take your eyes off the road to check two controls to know roughly what gear you are in...

I most certainly do not have to do any such thing; I can feel with my hand where the levers are positioned and therefore which gear I am in very easily. This is assuming that I have forgotten where I left them the last time I changed gear.... which I would suggest is akin to forgetting what the time is having just looked at your watch....

On some of my bikes I have the levers on the handlebars within easy reach; it Is really no problem at all. Needless to say if you use STIs or trigger shifters you cannot do quite the same thing, which is one reason why I don't have these on very many bikes.

I find that the whirring noise in the low gears is useful as it tells you when you have changed into the low range without having to take your eyes off the road and look at the gear changer.

I know what you mean, even with an N7 you get to know the same thing for the same reason. But if the Rohloff hub is 'perfect', you surely shouldn't care about that...?

cheers

[syklist]

I know what you mean, even with an N7 you get to know the same thing for the same reason. But if the Rohloff hub is 'perfect', you surely shouldn't care about that...?

As someone learned on this thread once said...

In bicycle transmissions, perfection is still a way off, I feel; it is just a question which kind of compromises you want to make; if it were a simple choice, we'd all be using the same thing already, right?

Rohloff. Perfect? No. But far and away the least imperfect.

Now if only that pesky Nexus 8 twist grip shifted in the same direction as the Rohloff...

Edit : <thinking> A pair of cogs in a small gearbox somewhere between the gear changer and the Nexus that reverse the direction of cable travel? </thinking>

PS People complaining about the Rohloff noise are like people who, on upgrading from an Austin 7 to a Rolls-Royce complain that the electric clock in the dashboard ticks...

[Mick F]

Rohloff. Perfect? No. But far and away the least imperfect.

You could well be right.

Imperfections are (in no particular order) and by no means prohibitive:
Cost.
Fixed wide range.
Won't fit all bikes.

If I ever get a new bike, and I can afford it, it'll be Rohloff equipped I expect. I'll be so old, I won't mind the excess gear range, in fact I'll probably like it by then!

[Brucey]

the latest Alfine 8 hub (SG-S7000) has a reversed shift pattern and uses a different cassette joint etc.

I suspect that it may be possible to fit the new axle assembly into an older Nexus hub but

a) I've not tried it, so I can't say for sure, and

b) it wouldn't surprise me to find that they have (yet again) revised the driver and/or the seals that work on it, so you might find that you need the new driver to work with the new axle, and there is no cover that fits the Nexus hubshell and seals onto the driver correctly.

It might be that spending a few hours poring over the EV techdocs for the various hubs may tell you one way or another if it is likely to work or not. AFAICT the 'old' A8 hubs (SG-S500, SG-S501) used the same axle assembly as the Nexus 8 models and the 'New' SG-S7000 uses a lot of other parts that are the same as the older Alfines (but not the axle assy obviously), so it might just work out nicely...

cheers