Author Topic: [Part 2] Rohloff splined sprockets (and Chainglider fitment)  (Read 31307 times)

Danneaux

  • Administrator
  • Hero Member
  • *****
  • Posts: 8232
  • reisen statt rasen
[Part 2] Rohloff splined sprockets (and Chainglider fitment)
« on: January 20, 2016, 04:45:24 am »
Hi All!

As some of you have kindly told me, the original thread on Rohloff splined sprockets is coming up blank on the third page -- rather, it shows a server error and posts beyond the second page are not appearing.

I'm starting this second thread on the same topic so posts can be made while we look into things. I'll notify Adrian and hopefully if/when the original thread is recovered, I can merge the two into one topic.

As always, thanks for letting me know about any anomalies. I had found this one myself, but it is helpful to have confirmation.

All the best,

Dan.
Thorn Cycling Forum Administrator

macspud

  • Hero Member
  • *****
  • Posts: 730
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #1 on: January 20, 2016, 06:26:44 am »
Thank you Dan.

I deduce that the reason Rohloff have increased the chainline on their new splined sprocket & carrier system to 58mm is that there isn't clearance between the hub casing and the chain side plates when using 13 & 14 tooth sprockets at the old 54mm chainline. This is the same reason why the threaded 13 tooth sprockets have a 58mm chainline causing them to be asymetrical and therefore unable to be reversed.




macspud

  • Hero Member
  • *****
  • Posts: 730
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #2 on: January 20, 2016, 06:27:00 am »
Inportant information

For those wanting to use a Hebie Chainglider.
Rohloff are discontinuing sale and production of the existing threaded drive cogs.

From now on all cogs will be their new system of Splined Cog & Carrier.

As Dave Whittle said:

Quote
A very good point and may well be correct. If the Chainglider is placed 3mm further outboard it will be placed clear of any contact with the Rohloff shell. But as mine on the Nomad sits hard against the seat stay it's all a bit academic - a 3mm wider chainline will prevent use of the Chainglider that I now  value highly.

Best stock up on sprockets now, as this isn't going to be an option the new sprocket replaces the existing in all cases and stocks on the old sprockets are being run down.

The new cogs increase the chainling to 58mm making it too wide for use with a chainglider on most existing frames as there is insufficient room between chainline and seatstay.

In answer to the following emailed question to service@rohloff.de

"I have been reading about your new Rohloff Splined Sprockets and Splined Carrier. I have heard that the old threaded sprockets will be phased out and will no longer be available when existing stocks run out. Is that correct?

If it is correct, it will mean that the Hebie Chainglider much loved by many Rohloff Speedhub users, will no longer be usable on most/many existing frames. The extra 4mm added to the chainline leaves no room for the Chainglider."

I received the following answer:

"You are correct. The new splined sprockets will replace the older thread on style as stocks run out. A new batch of threaded sprockets will not be produced.

The splined sprockets move the chainline out by 3mm to bring the rear SPEEDHUB sprocket into alignment with the outer chainring position of modern cranksets.

The wider chainline will make fitting a chainglider tight in some frames but that is irrelevent because the new splined are constructed without the seal lip which current Hebie Chaingliders requires for mounting. As such there is currently no chainglider available from Hebie that will function with the new splined sprockets. Hebie have had to re-think their chainglider numerous times over the years due to poor design and I regret I am currently unaware as to whether Hebie plan to do this again for the new splined sprockets, or drop it from their product catalog completely."

Unfortunately, what I saw as a possible expanding of Rohloff/Chainglider compatible gear ratios, seems to be in actuality a possible end to Rohloff/Chainglider compatibility completely.  :(

Is it true the the Chainglider Rohloff compatible rear end sits on the seal lip of the threaded rohloff cog?

Better stock up before the rush.









« Last Edit: January 20, 2016, 06:49:28 am by macspud »

macspud

  • Hero Member
  • *****
  • Posts: 730
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #3 on: January 20, 2016, 06:32:31 am »
The new Splined carrier could be machined to have the same 54mm chainline as the theaded system if cogs below 15 tooth count are not used.
A surface like the current seal lip would have to be added to use with current Hebie Chainglider rear ends.
« Last Edit: January 27, 2016, 08:36:51 pm by macspud »

macspud

  • Hero Member
  • *****
  • Posts: 730
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #4 on: January 20, 2016, 06:37:23 am »
The splined sprockets move the chainline out by 3mm to bring the rear SPEEDHUB sprocket into alignment with the outer chainring position of modern cranksets.

This seems to re-open the debate as to whether the new Chainline is 57mm or 58mm.  ??? :-\
« Last Edit: January 20, 2016, 06:50:20 am by macspud »

rualexander

  • Hero Member
  • *****
  • Posts: 908
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #5 on: January 20, 2016, 09:02:47 am »
Quote
The splined sprockets move the chainline out by 3mm to bring the rear SPEEDHUB sprocket into alignment with the outer chainring position of modern chainsets.

I have my chain on the middle chainring position and a Thorn chainguard ring on the outer position, so that will no longer be an option either if ideal chainline is desired.
Seems like a bit of a backward step to solve an issue that wasn't really an issue (changing sprockets more easily), but creating other issues.

mickeg

  • Hero Member
  • *****
  • Posts: 2709
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #6 on: January 20, 2016, 03:55:49 pm »
I suspect that Rohloff in developing a new splined carrier did it with (1) the most simplified engineering that was practical  (2) while minimizing manufacturing costs and (3) without significant reduction in reliability or durability.  Thus, I am confident that maintaining chainline was of little importance to them.  I would be surprised if anyone on the engineering staff ever initiated a discussion on that as long as the chain would not rub on any frame parts.  I am an engineer and that is the way I would have done it.

Derailleur bikes commonly are used more than 5mm outside of an ideal chainline.  I have commented before that when I built up my bike I included a chainline error of 5mm for personal reasons.  I am sure it reduces my chain life a little, but I am not going to let that be the driving factor.  But for me personally, if I switch to the new hardware my chainline error becomes 9mm, which I see as more significant.  In my case it would either mean needing a longer bottom bracket or moving my chainring to the outer position, losing the bash guard.

For the chain glider crowd, it is problematic too.

But I will not fault Rohloff for doing it this way, it would be more costly to design and construct a carrier system that maintained the same chainline and as a manufacturer, they have to look at those issues too.
« Last Edit: January 20, 2016, 03:59:39 pm by mickeg »

Andre Jute

  • Hero Member
  • *****
  • Posts: 4070
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #7 on: January 20, 2016, 07:18:55 pm »
In a careless and reckless letter, service@rohloff.de wrote to our own MacSpud:
Quote
"The wider chainline will make fitting a chainglider tight in some frames but that is irrelevent because the new splined are constructed without the seal lip which current Hebie Chaingliders requires for mounting. As such there is currently no chainglider available from Hebie that will function with the new splined sprockets. Hebie have had to re-think their chainglider numerous times over the years due to poor design and I regret I am currently unaware as to whether Hebie plan to do this again for the new splined sprockets, or drop it from their product catalog completely."

No, it isn't "irrelevent" (sic) that the redesigned Rohloff sprocket, soon to be the only Rohloff sprocket, will cause the chain or a Chainglider if fitted to interfere with the frame. That's careless of customers with tightfitting frames and/or a preference for Chaingliders.

It gets worse. When customers liked the Hebie Chainglider, designed for hub gearboxes with vastly larger markets than Rohloff, so much that they fitted them to the Rohloff, which then got in the way of the Chainglider and wore ridges (a perfectly valid alternative view to the one in the quotation given above), Hebie redesigned the rear end of the Chainglider to suit the Rohloff. The correct way to look at this is that Hebie, a large firm, did a smaller one, Rohloff, a very substantial favour, in accommodating a few Rohloff customers who were never going to be a major profit centre. But some insensitive idiot at Rohloff describes this in writing as "Hebie have had to re-think their chainglider numerous times over the years due to poor design", as if Hebie should have designed their Chainglider from the beginning to take account of the peculiarities of the Rohloff gearbox. In fact what Hebie did was to bend over backwards to adapt to changes in the shapes and dimensions of any and all hub manufacturers with a market presence that justified it, plus Rohloff. It would serve Rohloff right if Hebie now said, "Look, those mudpluggers don't want us, so to perdition with them." But it won't serve Rohloff's minority of non-mudplugger customers (tourers) who like the Chainglider well at all -- in fact, it would serve them very badly indeed. That is what I mean by a reckless letter.

Did you get this fellow's name, MacSpud? When my Chainglider no longer fits my Rohloff because of Rohloff's carelessness of customers and their reckless offense to Hebie, I want to send him the dry cleaning bill for the oily bottoms of my trousers.

"Irrelevent" (sic), indeed... This whole affair is very unlike Rohloff. I bet we'll discover that the letter to MacSpud was written by a junior exceeding his authority or an engineer (widely known to be an insensitive breed) overextending his grasp of English. I certainly hope so. But if not, my answer is above, and here is the executive summary:

As both a Rohloff and a Chainglider customer, I hope this post makes it quite clear to Hebie that service@rohloff.de doesn't speak for me. I adore Hebie. And their Chainglider is one of the best products to come on the market for bicycles in the last couple of decades.
« Last Edit: January 23, 2016, 12:40:44 am by Andre Jute »

macspud

  • Hero Member
  • *****
  • Posts: 730
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #8 on: January 20, 2016, 09:27:02 pm »
No, it isn't "irrelevent" (sic) that the redesigned Rohloff sprocket, soon to be the only Rohloff sprocket, will cause the chain or a Chainglider if fitted to interfere with the frame.That's careless of customers with tightfitting frames and/or a preference for Chaingliders.

Andre,

I totally agree. I was amazed by the tone of the reply. It was because of the tone that I decided to post a copy of the reply, otherwise I would have given the gist in my own words.


But I will not fault Rohloff for doing it this way, it would be more costly to design and construct a carrier system that maintained the same chainline and as a manufacturer, they have to look at those issues too.


mickeg,

On the contrary, to construct a carrier system that maintained the same chainline would be very easy, all they would have to do is not add the 4mm. The reason they added 4mm to the chainline was to accommodate 13 & 14 tooth sprockets without the chain side plates contacting the hub casing.
« Last Edit: January 20, 2016, 09:32:41 pm by macspud »

mickeg

  • Hero Member
  • *****
  • Posts: 2709
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #9 on: January 20, 2016, 09:30:49 pm »
It sounds like he was saying that the chainglider would not work with the splined system at all.  And therefore I think he was saying that the change in chainline was "irrelevant" to that discussion.

Maybe he is not a native english speaker, if so perhaps a native english speaker might have chosen a different word.

mickeg

  • Hero Member
  • *****
  • Posts: 2709
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #10 on: January 20, 2016, 09:48:36 pm »
...
mickeg,

On the contrary, to construct a carrier system that maintained the same chainline would be very easy, all they would have to do is not add the 4mm. The reason they added 4mm to the chainline was to accommodate 13 & 14 tooth sprockets without the chain side plates contacting the hub casing.

Yes it would have been possible to have done it in a way that maintained chainline, but this is how I would have done it too.

http://www.rohloff.de/fileadmin/_processed_/csm_splined_c178ea2ae6.png

il padrone

  • Hero Member
  • *****
  • Posts: 1322
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #11 on: January 22, 2016, 11:35:28 pm »
What a cock-up !!!  >:(

Not happy Jan. Wonder whether SJS now have any threaded sprockets still in stock. I will need a supply eventually.

il padrone

  • Hero Member
  • *****
  • Posts: 1322
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #12 on: January 22, 2016, 11:58:13 pm »
Is it true the the Chainglider Rohloff compatible rear end sits on the seal lip of the threaded rohloff cog?

No. This part of the repliy I do not quite understand. My Chainglider has a good 4-5mm space from the hub on the inside. On the outside it does (sort of) ride on the lip of the sprocket, but this is in no way essential to the fitting of the Chainglider - it  is held in place mainly by the spacing and position over the whole drivetrain.


Better stock up before the rush.

Planning my next order as we speak. Maybe all of this is just a sales pitch to help SJS along ???

il padrone

  • Hero Member
  • *****
  • Posts: 1322
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #13 on: January 23, 2016, 12:06:36 am »
I f the previous 13 & 14 sprockets ran on the hub with a 54mm chainline, why is it not possible for them to run with the new splined sprocket plus carrier ??? Surely in either case, if the chain is going to rub the hub on one, it would be doing so with the other design ???

Danneaux

  • Administrator
  • Hero Member
  • *****
  • Posts: 8232
  • reisen statt rasen
Re: [Part 2] Rohloff splined sprockets (and Chainglider fitment)
« Reply #14 on: January 23, 2016, 01:24:23 am »
Quote
I f the previous 13 & 14 sprockets ran on the hub with a 54mm chainline, why is it not possible for them to run with the new splined sprocket plus carrier...
Pete,

The current screw-on 13t sprocket requires a 58mm chainline (Rohloff say 59mm here: http://www.rohloff.de/en/service/faqs/index.html ), not 54mm as with the other screw-on cogs.

The reason is the small diameter of the 13, which could allow the chain (or at least debris attached to it) to rub on the hub shell. By offsetting it (it has a deeper flange), there are no clearance problems...but it is non-reversible. The larger diameter cogs elevate the chain safely above the hub shell and have not required the offset.

The new splined carrier system has rationalized the offset so all cogs regardless of diameter will fit the same carrier, a design failsafe.

All the best,

Dan.
« Last Edit: January 23, 2016, 01:52:28 am by Danneaux »