Gebla Rohbox thoughts
 

We have had a Rohloff hub on our Speedster tandem for several years and cycled at least 15,000 miles in that time. The Rholoff addressed the chronic shifting issues I had previously experienced centered on the triple crank. It reliably failed to shift to the granny gear when starting up a steep hill, a rather frequent event here in West Virginia. With our Rohloff setup we had Co-Motion’s version of the twist handlebar shifter which once set correctly was tough and reliable. However, it needed fine tuning during reassembly at the beginning of a tour and I still hadn’t mastered the fine art of getting it set just right. Sometimes I would end up only having 13 of the 14 gears working or the gear indicator arrow only roughly pointed to the correct selected gear. If I succeeded in adjusting it correctly I often didn’t know what I had done that was key to that success. I had to wear a bicycle glove to get enough friction if the shifter was at all wet from rain or sweat. But that wasn’t my main issue with the shifter. I don’t like having to take my hand off the handlebar or brake hood to twist the shifter. I tend to swerve the tandem, an unnerving experience when grinding up a hill with traffic passing too closely. On a recent tour we had a set of heavily loaded rear panniers which exacerbated the situation. A tandem friend showed me the Gebla Rohbox he had installed on his bike, so when we returned from the tour I decided to make the switch. Here are observations about the process.

-I purchased the Gebla Rohbox from Cycle Monkey. The kit cose $575 which included the Rhobox shifter.
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The Rohbox replaces the shifter box attached to the bottom of the Rohloff hub. The case turned out to be slightly smaller at the top which was an advantage in my case as the original shifter was too snug against the wheel stay. The instructions were translated from German, but with the pictures I was able to figure out the minimal modification necessary, which for a 4 year old Rohloff required removing a small plastic ring insert.

-Cycle Monkey made the modification to the SRAM Rival 22 Mechanical Brake Shifter (Brifters) which was a relief. Unexpectedly, they also included brake and shifter cable and housings sufficient for a single bike.

-The directions indicate the system should be installed by an experienced mechanic. Good luck finding an experienced tandem bicycle mechanic or any mechanic who had seen a Rohloff anywhere near here, so I had to do. In my case what I had learned about derailleur adjustments over the years helped, but there was still a learning curve. Gebla relies on two shifting cables. I elected to have the right SRAM brifter pull cable to shift to one or two higher gears. The left brifter pulls cable to shift to one or two higher gears. Each cable pull engages a pawl against an oversized cog which replaced the smaller cog on the original Rohloff shifter. This larger cog provides the increased leverage necessary for shifting with a brifter.
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The oversized cog is in the center. The pawl that engages the cox is just visible next to the spring and attached to the bronze colored block that secures the shifter cable.

-When I first looked at the Gebla Rohbox and even after installing it, I feared the pawls would be too fragile to stand up to repeated shifting, especially if I tried to shift from gear 14 to 15, which doesn’t exist. Apparently, the engineer had me in mind because it seems to be more robust than it initially appeared. It’s likely that I’m not able to put enough force on the brifter shifter paddles to bend the pawls. The oversize cog also lessens the amount of force needed to shift the gears.

-Once I made the correct adjustments by turning the barrel adjusters the shifting has been excellent, even on our hilliest routes. I no longer feel like I have to be overly gentle with the shifter. Although I frequently don’t realize when I’m in gear 1 or 14, an additional shift attempt feels different and I stop long before damaging a pawl. Before a long or international tour I will probably order a spare Rohbox shifter. It’s compact, light and costs only $253.

-With the Co-Motíon twist shifter I liked being able to shift a lot of gears at one time, usually about four gears. Now I’m limited to one or two gears. I’ve noticed that when stopped at an intersection I quickly got used to just doing multiple shifts to get to an appropriate starting gear. Since I no longer have to move my right hand to twist the shifter I tend to shift more often. In our hilly area I usually made two shifts at a time while now I tend to more often make one shift. I no longer have problems with the tandem swerving while shifting.

-The Co-Motion twist shifter was robust and required only minimal maintenance. However, it did start to make some noise when shifting when the cables aged and perhaps needed some lubrication. After several years I had significant difficulty getting one of the old cables out of the shifter when I wanted to replace them. This time, after only six months one of the cables would not come out in spite of using every kind of lubricant and penetrating fluid I threw at it. I had hoped to keep the twist shifter in reserve on the shelf but ended up just throwing it away. That old cable is never coming out and I could see no way to take apart the shifter. I’m glad that didn’t happen somewhere on a tour.

The switch to the Gebla Rohbox has been a complete success. I always hoped Rohloff would finally release an electronic shifter for our system, but I’m no longer sure I would bother to make a change to an electronic shifter.
Dave Fritsch

A nicely detailed report of the Rohbox, thanks. We have flat bars and the rohloff twist grip works well for us/me, the hand movement to/from brake lever is minimal. I often shift 8'ish gears after stopping at the bottom of a valley where they MUST put a stop sign:) After many years of touring with tandem and single with drops, I very much like MTB brake levers. Changing from derailleur to rohloff has worked out well, shifting is linear and operationally smoother. People argue that the rohloff is heavy and expensive, but 1 pound on a loaded touring bike is insignificant and the maintenance cost is nearly zero, so over time comparable.

WVDave: sorry to hear about your swerving problem with the shifter. I have a Co-Motion Pangea Rohloff. I had no problem with the Co-Motion shifter except it wasn't left handed. I used the Rohloff lefty shifter on a crazy bar for several years. I Went back to drop bars and tried the HubBub that mounts like bar end shifters. I have now ordered a Thorn accessory bar to mount it on. The rohloff brand shifter has ball bearings in it and shifts much nicer than the Co-Motion shifter. I never had trouble with bar ends on our tandem and have no control problems with anywhere I mount the Rohloff shifter. I believe you can pull the Co-Motion shifter apart. Call them and ask how. I only use Rohloff or Nocon inner wires on my shifters. I keep several extra sets to avoid out of stock orders. I did consider the rohbox but didn't like the idea of only being able to shift one or two gears at a time. I have also considered the Shiftezy Electronic Rohloff Shifter.

Shiftezy & Hubub
 

“Went back to drop bars and tried the HubBub that mounts like bar end shifters…. I have also considered the Shiftezy Electronic Rohloff Shifter”
I had never heard of the Shiftezy. I’m not sure what would be involved in fitting it to my Rohloff and I’m not sure I would want the appendage sticking out the back. As far as the Hubub, I was trying to get away from having to remove my hand from the brifter. I’ll still be interested if someone creates a compact electronic shifter that attaches to the existing hardware on my Rohloff. Actually, I’m disappointed that Rohloff hasn’t done so already.
Dave

Starting in 2024 Pinion has a version of there 12 speed with electronic shift. You can see it as a pre order on the Priority bicycle site. You can't add it to an existing Pinion. You have to buy that version of the Pinion. You can only get a Rohloff ebike with electronic shift. I would also like to have electronic shifting on my Rohloff. I put the HubBub on my 48cm Nitto Noodle and didn't like how far it sat out there. I considered cutting off some of the left drop to make it even with the other side also. The Thorn accessory bar replaces spacers just below the stem. It extends 75mm forward of the fork. 23 Ways to Run Rohloff Shifters with Road Drop Handlebars

When we bought our coupled, Rohloff Co-Motion tandem in 2016, we had the Gebla shifter/Rohbox installed right away (we still have the original, unused Rohloff shifters). We’ve never had an issue with the Rohbox after 55,000 miles and extensive touring in Europe and the US and have been pleased with the reliability and performance of the shifting mechanism. Until now. We just returned from cycle touring Puglia, Italy in late October 2023 and reassembled the tandem when we got home. I could not shift into the higher gears - the shifter (brifter?) would just click but not actually shift up. I’m very familiar with how the Rohbox works, but couldn’t figure out the problem. We felt fortunate that the part broke AFTER we returned home or we would not have been able to do our cycling tour.

I took the tandem to our tandem-only shop in Denver, where the owner/mechanic Kevin examined the Rohbox. He quickly saw that one return spring was shorter than the other and realized the spring had broken (the break was hidden in the brass transport block). He is contacting Cycle Monkey to see if he can get replacement springs. If they can’t provide a spring, he’ll check hardware stores for a replacement and hope that the spring weight is effective. Otherwise, we’ll have to “spring” for a new Rohbox.

So this raises the question of travel spare parts on a bike with 55,000 miles on it. We carry backup carbon fiber belts, spare cables and spokes, along with small parts such as seat tightening collars, screws, etc., but not spare a backup Rohbox - something that can’t be found easily. We also don’t carry along a backup Roholff hub either (and have had no problems with it). Thoughts?

You definitely have gotten plenty of miles without failure on the Rohbox. I have a friend who was a helicopter mechanic in the military. He told me that the parts on the helicopter are rated for so many hours then replaced not repaired. I would replace those springs if possible or the whole thing in your situation after so many miles before failure. I am waiting for a Thorn accessory bar from SJS Cycles in England. I had my Co-Motion shifter on one previously before I went to a MTB bar type and switched to the left handed Rohloff shifter. I have had stem, down tube and barcon shifters with drop bars over the years. Alee from cyclingabout has done over 20,000 kilometers on his Tandem with the Thorn accessory bar shifter mount. I would consider this as a backup setup for your Tandem and have the parts needed ready to ship in case of an emergency.

Excellent postings on this narrow topic! I wanted to provide an update on my Rohbox after picking up the bike from the shop. Kevin, the mechanic/store owner, had not heard back from Cycle Monkey, so he went to Ace Hardware to find replacement springs. He DID find them, although they’re not exactly the same (see photo - the original spring is the smaller one in the middle, and the two on the outside are my spares, with two new springs installed in the Rohbox). The new springs are a bit more firm, but in riding with them, they seem to perform even better than the originals because the tactile feedback is much more satisfying. The shifting is crisp and responsive, so the only unknown is the longevity of the replacement springs. But with two spares, I’ve hopefully covered that point of failure. Note that the springs are larger, and therefore don’t fit into the ferrule inside the box, but that doesn’t seem to have any negative impact.

I do like Rick’s suggestion of having a backup set of parts that could be shipped if necessary, rather than bringing along parts not as likely to fail. This type of discussion reaffirms the value of this form!

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I wanted to add an anecdote to the discussion. While cycle touring on the tandem in Germany and the Czech Republic in 2017, we came across an American couple riding their tandem. After the usual type of discussion, we learned they were on their way to meet up Georg Blaschke, the inventor of the Gebla Rohbox shifter; GEorg BLAschke!). The couple was from the state of Washington, and he worked for a Bike Store, but he and the store mechanic could not get the Rohbox to work. They had contacted Georg and he agreed to install the shifter. We had exchanged emails and they later wrote to let me know Georg installed the Rohbox and they continued their cycle tour with it!

The Rohbox is a nicely built specialized piece of equipment. I am glad to see you have it running again. You ride a lot of miles and depend upon it. You can't know what might break next so having a shippable replacement part or even carrying a rohloff shifter in case of breakage might be a good idea. The Rohloff itself has proven to be quite reliable. I read that A fair amount of world travelers use the Rohloff. Do you carry a spare belt. I know of two belts breaking. one from abuse by Ryan Van Duzer and the other was just worn out. Alee from Cyclingabout had near 32,000 kilometers on one of his bicycles before he broke a belt.

And I thought you were going to say you found the replacement springs in the ball point pen.

FWIW: I am so satisfied with my Gebla equipped Bessie with cable operated hydraulic brakes, I decided that maybe I'd like to order another. So in searching for parts & researching options for the prospective new bike build, I was told that Shimano shifters can not be modified and that SRAM is my only option if I were to go for a straight all hydraulic brake system. That was a real downer because Shimano's mineral oil systems are moreorless maintenance free after initial install & bleed. SRAM DOT oil on the other hand IME sucks water out of the air with aplomb, eats seals, and SRAM, when they want to sell a new brake/shifter system, they discontinue the rebuild kits necessary.

Thankfully, I was lied to! Georg has Shimano GRX/105 Shifter pod dummies available! You just need to order from him directly via his website. He only uses Wise as a payment service, though. Thanks to him, I have a set of GRX pods & another Rohbox on the way, shipping Monday! Hooray 🥳

TLDR: For all you road handlebar Rohloff users You are not locked into SRAM road shifters anymore. Oh happy day! :ride:

😆 I added the pen to provide a size reference. But we did consider a spring from a pen…

base2, it’s great to know there’s a real option - thanks for the PSA! We use a TRP HY/RD hydraulic brake on the front actuated by a manual cable pull - so yet another option.

What brake levers are you using with The TRP HY/RD. I could not get enough brake lever pull and they overheated and blew out the fluid. My Co-Motion pangea Rohloff came with the Spyre that was on a recall. I put the HY/RDs on and when I had problems I went with the Paul Klampers. Paul says to use the old school coiled brake housing. I put on the Yokozuna compressionless housing instead. The Klampers are so wide, that were the cable enters the caliper there was friction from the inner wire rubbing. I solved this with Jagwire lined end caps. If I didn't have SS couplers I would have gone full hydraulic brakes.

HY/RD are road/short pull. So any road lever should work. As far as blowing out, that should never be a concern. There is something wrong there. With pads installed and a rotor in between there can not be enough room to do so. With no rotor & pads only in the caliper, the pads ought to just hit eachother and stop. Ideally this is true even if worn to the metal backing.

The only way to over-stroke and blow out the pistons in hydraulic brakes is with the pads removed, no rotor and repeated lever pulls to push hydraulic fluid behind behind. Even 1 or 2 errant lever pulls is a situation that can be recovered from IME.

To recover from over-stroked pistons or to prepare for new pads, insert a flat bladed screw driver or similar instrument in the caliper and simply twist to push the pistons back until they are fully stopped. Only do this with pads installed or protection of some sort. Unprotected ceramic pistons will crack under normal force of a screwdriver. I don't know whether HY/RD's pistons are ceramic or not. Just throwin' it out there.

Good practice is to never pull a brake lever with out the wheel (with rotor) installed in the bike and if ever the wheel is removed insert a dedicated factory supplied dummy or a generic piece of cardboard.

It was the fluid that blew out and I sent the brakes to TRP. They mailed the replacements the same day I sent the brakes to them. The Crane Creek SCR-5 levers that came on my bicycle are short pull levers. I couldn't stand the little bit of pull the HY/RD offered. I have Three sets of slightly used calipers in my tool box. The Paul Klampers are on my bicycle.

Oof. Sounds like a manufacturing defect then. No worries. Carry on.
Base2

base2 has covered the braking questions - I’m using the SRAM brifters that came with the Rohbox from Cycle Monkey.

We also heard back from Cycle Monkey regarding replacement springs, and they don’t sell just the springs. There’s a small package of parts which includes the springs, although we didn’t get a price for that.

Abandoned the Gebla Rohbox
 

Well, I circled back to near square one. In my last post on this topic late October 2023 I judged the Gebla Rohbox install to be a "complete success". I continued to be happy with the setup as we cycled into the cooler weather. However, the first time we rode the bike on a cold day after it sat in our unheated garage for two months we had shifting glitches. It felt like the spring loaded shifting pawl was not retracting with the result that it was not possible to shift either higher or lower. We had to get off the bike and jiggle the shifter cables to get it to release. After the third instance, I no longer had confidence in the system. I had planned to contact Cycle Monkey to purchase a set of replacement small parts to take on tour but, as others noted, they seem to be out of business. I ended up reverting back to the Rohloff external rear shifter and purchased the Rohloff handlebar shifter which does not easily work with drop bars. I went ahead and converted to flat handlebars (with a slight 1" rise) and installed Ergon GP4 Lock-On Handlebar Grips which actually give me more comfortable hand positions than I had with the dropbars. Note, Ergon sells a special size right hand grip designed to work with the Rohloff shifter. I had to source that directly from the Ergon supplier. The slightly wider right grip results in the right brake lever being sited slightly closer to stem, something I thought would bother me, but I don't notice it when riding. I purchased a set of $20 Avid cable brake levers which seem to do the job. We've been able to ride several times and the shifting is what I hoped for. I like the Rohloff grip shifter much better than the CoMotion one, partly because it fits my hand better and is not as slippery. Since my right hand is usually already resting on the flat part of the Ergon grip, I don't have to move my hand much, if at all, in order to make a shift. This prevents the bike from swerving while shifting when grinding up a hill with close passing vehicles. For the first time, I no longer care when or even if Rohloff finally releases electronic shifting. I probably wouldn't bother making a change, even if it was very low cost.
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WVDave, that’s a great solution and is what I will try if I have any ongoing issues with the Gebla box! An additional benefit is that the straight handlebar would be easier to pack into the bike case than drop bars.

If your committed to a Rohloff hub, this is an approach to improve it, and if it works for you great.

It appears to me however, that Rohloff is becoming a bit archaic in a world of electronic shifting and 12 speed cassettes.

By Rohloff’s own chart a 14 speed Rohloff offers the same number of usable gears as a 2x10 setup, nd covers a slightly smaller range than the 2x10.

https://cimg7.ibsrv.net/gimg/bikefor...194fe900b4.png


the range of a 2x12 would be even better.

With an upfront cost of more than $2000 for the hub plus this hack, a weight penalty of 1-2 pounds, and arguably a drivetrain efficiency loss. The case for Rohloff hubs seems to be shrinking.

i think you really have to value the cleanliness advantage and low maintenance for a Rohloff hub to make sense.

Given how good electronic shifting is, I would be inclined to put the $600 toward an upgrade to Di2 or SRAM wifi. For about $1000, you can get a complete SRAM Rival Axs, or Shimano 105 Di2 drivetrain. Admittedly, the setup for a Tandem would likely have some additional costs, but you’d also have a completely new drivetrain.

I agree with you to some extent. When we initially made the decision to switch to the Rohloff it was after a long struggle trying to get the traditional triple front chainring to shift reliably. We live in WV with very steep hills which required frequent shifts to the granny gear. Multiple mechanics, including tandem mechanics were unable to tune the front derailleur to be able to shift. It didn't help that many of the mechanics were located in the flatlands and the bike shifted adequately on their terrain, only to glitch again when we returned home. If I was personally able to tweak it to shift pretty well, after bike reassembly after a flight, it never once shifted correctly out of the box. At the time I couldn't find a 2X chainring that would get me to a sufficiently low gear range while not spinning out in the highest gear. After I switched to Rohloff I saw some SRAM electronic shifters on friends' tandems which seemed pretty reliable which I probably would have gone with instead of the Roholoff. Now with 2x12 available, it would have been even more attractive. Given that, on our most recent ride, it was wonderful not having any doubts about shifting reliability as we started up some of our 1st gear WV hills.

Nice to hear more about the Rohloff shifting. I went back to the Crazy Bars. Ergon only makes the Rohloff/Nexus grip for the right side. I had to cut down the left grip on a standard pair. If somebody goes to do this, you need to do a supported cut so the thin plastic inside the grip doesn't break up. I used the largest piece of dowel stock that would slide in the grip and added some electric tape. I have the cork vesion of the Ergon G1 grips. I really like my Cave Man Rohloff setup.
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I wouldn't have it any other way.

For touring with a tandem a Rohloff is especially good. The simplicity of operation and maintenance is better than derailleurs. The design is robust and has sufficient range for climbing 10+% hills while loaded and tops out at 28 mph. I very much like be able to shift at a stop sign to whatever gear I need to get started, and shifting +8 gears in a second when in hill country. It is unfortunate that the speed market tends to dominate bike components.