Thorn Cycles Forum

Community => Rohloff Internal Hub Gears => Topic started by: onmybike on September 21, 2018, 02:00:56 AM

Title: Drop bar shifter hack?
Post by: onmybike on September 21, 2018, 02:00:56 AM
I just came across this hack ( https://bikerumor.com/2018/09/20/budnitz-og-pedals-up-unique-limited-edition-titanium-gravel-grinder/ (https://bikerumor.com/2018/09/20/budnitz-og-pedals-up-unique-limited-edition-titanium-gravel-grinder/) ) on the bikerumors site:

Quote
The trick to the dropbar Rohloff setup, the Ø:G uses the shifters from a set of SRAM Force 22 road hydraulic disc brake levers with their internal ratcheting mechanisms removed to control the internally geared rear hub without a bulky, less ergonomic shifter à la the Gebla Rohbox mod.

Can anyone explain how this may work? I couldn't find any more detail on the Budnitz site and haven't heard of this mod anywhere else.
Title: Re: Drop bar shifter hack?
Post by: Danneaux on September 21, 2018, 03:33:54 AM
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Can anyone explain how this may work? I couldn't find any more detail on the Budnitz site and haven't heard of this mod anywhere else.
The Rohbox works on such a simple concept, it is difficult to grasp at first. Where other aftermarket shifters use internal ratchets and gear trains, the Rohbox uses the warping of a compressed spring to engage and move a gear.

All "brifters" must be modified to work with the GEBLA Rohbox. It involves removing the internal ratchet; the result is (depending on the brifter used) 1 or 2 shifts per stroke.The idea to use an existing brifter was a good one; all the needed hardware is already present and works readily with slight modification. Of course, the brifters can be restored later if needed for derailleur shifting.

You can read about what is required to modify at least some levers on the GEBLA site. I've included a Google translated version of the appropriate FAQ below:
https://translate.google.com/translate?sl=de&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.gebla.de%2FRohbox%2FRohbox-All-Inclusive.html&edit-text=

Some detail shots are here:
https://www.cyclingabout.com/gebla-rohbox-road-mountain-shifters-with-rohloff-hubs/

...and reports of some problems here:
http://forums.mtbr.com/internal-gear-hubs/anyone-else-have-problems-sram-gebla-rohloff-setup-1023579.html

The Rohbox has been discussed here before:
http://thorncyclesforum.co.uk/index.php?topic=11590.msg84335#msg84335
http://thorncyclesforum.co.uk/index.php?topic=12573.msg93303#msg93303
http://thorncyclesforum.co.uk/index.php?topic=4049.msg81629#msg81629
http://thorncyclesforum.co.uk/index.php?topic=11680.msg85199#msg85199
http://thorncyclesforum.co.uk/index.php?topic=11565.msg84150#msg84150

Best,

Dan.
Title: Re: Drop bar shifter hack?
Post by: mickeg on September 21, 2018, 04:04:51 PM
More options here, they keep updating this website as options appear.
https://www.cyclingabout.com/rohloff-hubs-with-drop-handlebars/

But some are not accurate, I use the Hubbub adapter,  a nice piece of machined aluminum but the show a photo of some piece of wood instead of showing the correct Hubbub adapter.


Title: Re: Drop bar shifter hack?
Post by: martinf on September 21, 2018, 05:22:28 PM
More options here, they keep updating this website as options appear.
https://www.cyclingabout.com/rohloff-hubs-with-drop-handlebars/

But some are not accurate, I use the Hubbub adapter,  a nice piece of machined aluminum but the show a photo of some piece of wood instead of showing the correct Hubbub adapter.

I now have Hubbub adapters on both my Rohloff bikes. I tried the accessory bar option, but didn't like it. Perhaps because I was used to bar end shifters on derailleur bikes.
Title: Re: Drop bar shifter hack?
Post by: mickeg on September 21, 2018, 08:06:20 PM
I too was used to bar end shifters on some of my derailleur bikes, I think I started using bar end shifters in the 1980s before derailleurs had indexing.

With bar ends I could have both hands on the bars where both hands could provide steering capability while simultaneously being able to shift.  I think that is why bar end shifters were used on touring bikes decades ago, back then it was bar ends instead of downtube shifters.

I tried a couple different ideas with the Rohloff shifter, but generally the shifter was close to the steerer tube and that hand could not effectively steer the bike.  There were times on steep uphills with bad gravel and cobbles, I wanted both hands on the bars where I had better steering control, but was unable to shift because the shifter was not where I could steer and shift simultaneously.  It was on one of those steep uphills with bad terrain that I decided that I needed to buy the Hubbub adapter as soon as I got home.

I did not want my cables to stick out sideways towards the headtube, but instead to go forward and under my handlebar bag.  Thus I use V brake noodles on the cables as the cables exit the shifter.  But I should have painted the noodles black before assembly.
Title: Re: Drop bar shifter hack?
Post by: John Saxby on September 21, 2018, 09:44:02 PM
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I use V brake noodles on the cables as the cables exit the shifter.

Nice touch, George.  (I nearly said "bodge", but your solution is way too elegant for that.) (I'd stick with silver noodles, too.)

Cheers,  John
Title: Re: Drop bar shifter hack?
Post by: rualexander on September 21, 2018, 10:17:43 PM

I did not want my cables to stick out sideways towards the headtube, but instead to go forward and under my handlebar bag.  Thus I use V brake noodles on the cables as the cables exit the shifter.  But I should have painted the noodles black before assembly.

You could use Origin 8 Super Noodle cable guides instead if you want black.
https://www.sjscycles.co.uk/brakes/origin8-super-noodle-pair/
Title: Re: Drop bar shifter hack?
Post by: mickeg on September 21, 2018, 10:50:01 PM

I did not want my cables to stick out sideways towards the headtube, but instead to go forward and under my handlebar bag.  Thus I use V brake noodles on the cables as the cables exit the shifter.  But I should have painted the noodles black before assembly.

You could use Origin 8 Super Noodle cable guides instead if you want black.
https://www.sjscycles.co.uk/brakes/origin8-super-noodle-pair/

Thanks, but I was thinking black fingernail polish.  I keep some of that on the shelf for touching up wear spots on my black racks.  It would have been easier before the install, but I can still touch it up while on the bike.  But have not gotten around to it, ... ... yet.
Title: Re: Drop bar shifter hack?
Post by: Danneaux on September 22, 2018, 02:08:50 AM
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Thanks, but I was thinking black fingernail polish.
I had real good luck covering my silver noodles with black heat-shrink tubing on my earlier Sherpa and current Nomad and now another bike as well. It has held up well and still looks as-new some six years later.

Best,

Dan.
Title: Re: Drop bar shifter hack?
Post by: onmybike on September 22, 2018, 03:40:56 AM
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The Rohbox works on such a simple concept, it is difficult to grasp at first.

Oh, perhaps I misinterpreted the bikerumour website quote. I took it to mean they don't use a Rohbox, which is why I thought it interesting...

Quote
...control the internally geared rear hub without a bulky, less ergonomic shifter à la the Gebla Rohbox mod
(bold is my emphasis).

If they do use a Rohbox then it all makes sense. Perhaps they're simply saying the shifter they've chosen to use is more ergonomic and less bulky than the one's usually used with a Rohbox? Unfortunately there are no photos of the shifter side of the back wheel in the bikerumour article or on the manufacturer's website so I can't see what they've done.
Title: Re: Drop bar shifter hack?
Post by: mickeg on September 22, 2018, 12:13:27 PM
I suspect that since they were writing about a bike and not writing a free-standing article about the shifter, they just got sloppy with some of their wording.