[Part 2] Rohloff splined sprockets (and Chainglider fitment)

[John Saxby]

Wonder whether SJS now have any threaded sprockets still in stock.

I just ordered a spare 17T threaded sprocket (in stock), to be picked up at SJSC when I visit Zumerzet a couple of weeks hence.

So many variables at play:

>   There's about 3-4 mm of clearance between my 'glider and the inner surface of my driveside seat stay. Hard to measure closely, but I think I could just manage another 3 mm of chainline with my current frame & 'glider.  Might have to do a bit more delicate shaving & filing of the plastic to ensure a 1 mm of clearance (thus achieving in spite of myself, the Jute/Kranich standard of excellence.)

>   Then again, my current sprocket shows no noticeable wear after ~5500 kms over 2 seasons.  How many seasons/kms can I reasonably expect from the current one?

>   Factor in, say, at least another 10-15 years of riding similar annual mileage -- maybe I'll need another (threaded) sprocket, some 8 - 10 years hence. Almost certainly the changeover will happen in a peaceful warm&dry workshop, not on tour somewhere, if for no other reason than a monster great chain whip would not fall readily to hand.

>   Fitting a splined sprocket might well mean ditching the 'glider, or waiting for Hebie to make an adapted 'glider; and would require a different bottom bracket. (Of course, the current one may need to be replaced before the sprocket wears out.)

Gaaaah!   I can't stand it any longer:  Keep the current setup, buy a threaded spare, and future-proof The Sprocket Question for as long as I can ride the bike.

If anyone asks for an example of being nibbled to death by ducks, show them this thread.   

[mickeg]

I do not use the chain glider, I am not going to bother stocking up.  When I eventually need a new sprocket, if the 16T thread on ones are no longer available I will just get the new one and if necessary a longer bottom bracket spindle to correct the chainline.

But if I see any clearance priced thread on 16T sprockets later, I might get one or two.  I would not be surprised if the current stock of thread on sprockets at some retailers goes on sale when the new ones come out.

[il padrone]

Thanks for the clarification re. the 13 & 15t sprocket fit, Dan. However I do not see why Rohloff could not make one version of the carrier for 13/15t users, and a different carrier with the normal chainline for 16/17t users. Simple solution that doesn't too much contradict their 'engineering principles' and still allows most to use their Chaingliders. Easy? Just too easy for the boffins to think of 

My Chainglider on the Nomad Mk2 is hard up against the RHS seatstay - zero option for a wider chainline.

Just ordered a selection of thread-on sprockets to last me (and the wife - if I convert her to a Raven frame and Chainglider) for at least 10-15 years.

[Andre Jute]

If anyone asks for an example of being nibbled to death by ducks, show them this thread.

Except in Australia, where there is probably a duck with a lethally venomous tooth on its beak. (For those hitherto blissfully innocent, 17 of the 20 most lethally venomous/poisonous animals in the world live in Australia, and that's not even counting the Ustase -- Yugoslave terrorists -- or Muslim terrorists. There's a reason us ockers are hard men!)

My 16T sprocket has 8600km on it without signs of wear. I don't think I'm sticking my neck out predicting that yours and mine will both last at least quadruple the 5500km you have now, double on the first side, and another 11K when reversed, 22K in all. I have a 16T spare, and I'll lay in another one when I order new tyres and tubes; that will see me out and probably the next owner too.

However, after thinking about it carefully, I've decided that the convenience and cleanliness of the Chainglider is far more important to the way I use my bike than the Rohloff gearbox. There is nothing that comes remotely close to replacing the Chainglider -- see
http://thorncyclesforum.co.uk/index.php?topic=2233.msg10717#msg10717 --
while replacing the Rohloff is now not only possible but might be a technically interesting journey. There's the Pinion, whose Porsche credentials impress me as a longtime Porsche driver, and there is the NuVinci, whose lesser range and CVT engineering perfectly suits my central electric motor, and whose optional automatic "gearshift" adds to its intrinsic strength by obviating high-torque jerks. So I already know where I'll go if the tone of that letter from Rohloff to MacSpud presages a change of attitude by Rohloff to customers.

Executive summary for the non-Anglophone: I'd rather give up the Rohloff than the Chainglider.

I'm rather partial to Peking Duck.

[energyman]

.........no problem if you go for a belt drive...........

[il padrone]

.........no problem if you go for a belt drive...........

Even more incompatible with my Thorn Nomad Mk2 (I'm not cutting a break in my frame just to be able to use a belt)

[mickeg]

.........no problem if you go for a belt drive...........

For around home use, I use a 44T chainring.  For hilly touring take out a few chain links use a 36T chainring.  Both with 16T Rohloff sprocket.

That would be a problem for a belt drive.

[macspud]

I received a follow up email from Rohloff, the body of which follows:

a thread on Thorns cycling forum has been brought to my attention and I would like to make a few points based on the questions raised as well as my previous email reply to you.

As one of the replies in the thread suggested, I used the word "irrelevant" in my last reply, with regard to the fact that the wider chainline alone was not the reason why the Hebie Chainglider would no longer fit and thus that point was irrelevant to the subject of frame clearance. I would like to apologize if my word choice misconstrued the point I was trying to make.

Further talks with Hebie since my last email reply do seem to show their positive interest in redesigning the Chainglider to accommodate our new splines sprockets - although this will most likely mean the Chainglider will rest completely on the chain as with other systems and as such will reduce system efficiency a little further. When, and indeed if this revised product will be made available is however still not certain. I am sure Hebie will publish these details once finalized (as will we on our various web-based platforms).

The original sprockets lie almost flush against the sprocket side seal and as such needed to be placed further out to accommodate a bedstop on the splined carrier to prevent the sprockets rubbing against the seal face. A wider chainline was unfortunately unavoidable when designing a carrier to accommodate splined sprockets.

I myself (a 15 year long Rohloff employee) will be exhibiting Rohloff products at the London Bike Show next month on the ISON Distribution booth. If you or any of your fellow forum members have the time to come along and visit, then I will be more than happy to show you the various new products and talk through the reasons why these have been designed as they are.

It's good to Know that Hebie are interested in redesigning the Chainglider to accommodate the new splined sprockets.
Unfortunately the new chainline will most likely make a chainglider unusable for most existing Thorn frames (and many other brand frames, for that matter) which can use a Chainglider with the existing 54mm chainline. For a Chainglider to be usable with them, it would be Rohloff that has to redesign the splined carrier.

Are any of you thinking of visiting the London Bike Show?

[Andre Jute]

Are any of you thinking of visiting the London Bike Show?

Now that's more like it! That's the Rohloff we know and love. You're wasted on cycling, Iain; you shoulda been a diplomat: Lord MacSpud of the Congress of Vienna!

HEBIE'S INTENTIONS VIS A VIS THE CHAINGLIDER AND THE NEW ROHLOFF SPROCKET

I'm particularly glad to hear that "Hebie since my last email reply do seem to show their positive interest in redesigning the Chainglider to accommodate our new splines sprockets", but my joy is altruistic, for those whose bikes have more space in their rear triangle. It won't fit my bike. There just isn't the width.

HOW THE CHAINGLIDER WORKS

I'm also happy to discover from an authoritative source how the Chainglider works with the Rolloff  -- the back end rides on the lip of the threaded sprocket and holds the Chainglider clear of the chain, which accounts for the Chainglider inside being so innocent of chain oil. Also interesting that the Rohloff-specific Chainglider apparently causes less drag than the generic kind for cheaper boxes, which rides on the chain.

AN OPPORTUNITY TO PUT OUR VIEWPOINT

Moving on to practical politicking, if a forum member were to take up the invitation to speak to a Rohloff representative at the London show, what do we want him/her/it to say? Besides the man from Rohloff, who issued the invitation, there might also be someone from Hebie, so another opportunity opens up. Could I suggest you copy the text below and add your own numbered items.

AGENDA FOR THE MAN FROM ROHLOFF

1. We love Rohloff, of course.

2. The very minimum Rohloff should do to keep faith with customers is to maintain the spinner sprocket in production at the present high quality so that customers' expensive frames aren't made obsolete by a component manufacturer making a hostile specification change. This business of stopping manufacture of the threaded sprocket isn't just contrary to existing customers' interests but to the whole Rohloff ethos of keeping the gearbox working forever. If you can't get consumable parts for a component that continue to fit to and work with preexisting machinery, the component itself instantly becomes surplus to requirements.

3. As has been demonstrated, the Hebie Chainglider is important to some Rohloff owners. We would appreciate it if Rohloff would facilitate Hebie's production of not only a Chainglider for the splined sprockets, but for a wider variety of chainrings that work with existing and future Rohloff-fit Chainglider back pieces.

4. Rohloff has entirely overlooked the roadie market (for instance to reduce maintenance on winter training bikes), which finds a 54mm tread factor (Q) undesirable and a 58mm Q unacceptable. They demand a narrower Q, say 46mm.

5.

AGENDA FOR THE MAN FROM HEBIE

1. We love the Chainglider. We're big boosters of it.

2. The Rohloff gearbox for practical purposes lasts forever, so the threaded sprocket sizes will constitute a market for Chaingliders for many years yet.

3. Some of us would love to love the Chainglider but Hebie doesn't make a suitable chainring cover to work with the existing Rohloff 15-17T back end. (Some specific sizes like a 36T front end, for which we know there is a demand, could be mentioned.) The lowest sprocket ratio Rohloff permits is currently 1.9.

4.

[John Saxby]

Well said, Andre.

("London Bike Show", eh? So that's what LBS means!)

[Dave Whittle Thorn Workshop]

AN OPPORTUNITY TO PUT OUR VIEWPOINT

Moving on to practical politicking, if a forum member were to take up the invitation to speak to a Rohloff representative at the London show, what do we want him/her/it to say? Besides the man from Rohloff, who issued the invitation, there might also be someone from Hebie, so another opportunity opens up. Could I suggest you copy the text below and add your own numbered items.

AGENDA FOR THE MAN FROM ROHLOFF

1. We love Rohloff, of course.

2. The very minimum Rohloff should do to keep faith with customers is to maintain the spinner sprocket in production at the present high quality so that customers' expensive frames aren't made obsolete by a component manufacturer making a hostile specification change. This business of stopping manufacture of the threaded sprocket isn't just contrary to existing customers' interests but to the whole Rohloff ethos of keeping the gearbox working forever. If you can't get consumable parts for a component that continue to fit to and work with preexisting machinery, the component itself instantly becomes surplus to requirements.

3. As has been demonstrated, the Hebie Chainglider is important to some Rohloff owners. We would appreciate it if Rohloff would facilitate Hebie's production of not only a Chainglider for the splined sprockets, but for a wider variety of chainrings that work with existing and future Rohloff-fit Chainglider back pieces.

4. Rohloff has entirely overlooked the roadie market (for instance to reduce maintenance on winter training bikes), which finds a 54mm tread factor (Q) undesirable and a 58mm Q unacceptable. They demand a narrower Q, say 46mm.

5.

AGENDA FOR THE MAN FROM HEBIE

1. We love the Chainglider. We're big boosters of it.

2. The Rohloff gearbox for practical purposes lasts forever, so the threaded sprocket sizes will constitute a market for Chaingliders for many years yet.

3. Some of us would love to love the Chainglider but Hebie doesn't make a suitable chainring cover to work with the existing Rohloff 15-17T back end. (Some specific sizes like a 36T front end, for which we know there is a demand, could be mentioned.) The lowest sprocket ratio Rohloff permits is currently 1.9.

4.

I've asked representatives from high up in both companies these questions before, from Hebies point of view the tooling to make chain glider parts is very expensive, this means the have to pick the sizes they think they can sell the most of.  They have done lots of market research with end users and OEM's. Its the same answer when I have asked for the front end to accommodate wider rings, same response was given.

Rohloff are a very amenable company and co-operate very well with people designing parts for the Speedhub (we know this because of when we made the 19T sprockets) even parts they don't have 100% faith in like the Chain Glider, Gates Carbon Drive, Cinq 5 flat bar shifters etc, I've no doubt they will help Hebie as much as they can or are requested to but at the end of the day they can't make them do anything.

The reason Rohlof have "overlooked" the road market is that the hub isn't a road hub nor is it marketed as such, the spacing is wrong 135mm vs road standard 130mm, as you have pointed out the chainline is well out.  The hub is too heavy for road bikes and the gears are too far apart. The closest roadie bike that I know of in production would be a Thorn Mercury or VN Amazon style bike, neither of which you would see at anything more brisk than a sportive event.

I can't speak for Rohloff and it perhaps would be worth asking Stewart from Rohloff if there is a reason behind discontinuing direct fit sprockets by I imagine its due to the minimum order run for producing the sprockets and the low number of sprockets they would sell in comparison. Feedback I've had from most customers here is they can't wait for the new type to come out.

[mickeg]

Thanks Dave for your perspective.

Co-Motion Americano is also a drop bar bike with road geometry that is available with Rohloff, but it is a robust (heavy) frame for touring, thus the light weight roadie crowd would likely show little interest.  Their frames are hand made and are quite expensive.  I suspect all of the Americanos stay in USA, thus you probably will never see one.

[geocycle]

Dave: so you don't see any problem with the extra spacing of the new sprockets on tight frames like the RST?

[il padrone]

I still don't see the huge difficulty in Rohloff selling two carriers - one for the 13 & 15t sprockets, and a narrower one for the 16 & 17t sprockets.

[Andre Jute]

I've asked representatives from high up in both companies these questions before, from Hebies point of view the tooling to make chain glider parts is very expensive... Its the same answer when I have asked for the front end to accommodate wider rings, same response was given.

Thanks, Dave. Everything you say is what we suspected. It's interesting that even for Thorn Hebie wouldn't make a fatter front end...

All the same, Rohloff would do their reputation as a company which builds permanent products -- and customers -- no end of harm if there were a lot of people faced with a choice of dropping other components or even trashing whole frames because Rohloff deserted them by discontinuing a part, the threaded sprocket, that is essential to their bikes.

("London Bike Show", eh? So that's what LBS means!)

Ever since I acquired my first sophisticated bike, I have suspected "local bike shop" is a euphemism for "goddamn unreconstructed blacksmith". May I should move to Bridgend and live in Dave Whittle's pocket.

I still don't see the huge difficulty in Rohloff selling two carriers - one for the 13 & 15t sprockets, and a narrower one for the 16 & 17t sprockets.

Exactly. Which is precisely what they've done for years and years, the 13T sprocket being a completely different, non-reversible, design to the 15-17T reversible design. Which is why I can't see why keeping faith with existing customers by keeping the threaded sprockets available is such a big deal.