The Gebla Rohbox shifting system on a Co-Motion Equator, using modified SRAM Rival brifters. Note this allows use of carbon bars with a flat profile.
Rohloff hub on Co-Motion Java - external gear box.
As mentioned, the gear range spans 526%, in equal steps. Typical gearing is exemplified by the Co-Motion Equator, a touring/road tandem with a low gear of 19 gear inches and a high gear of 99.6 gear inches. This is equivalent to a 24/34 chain ring/cog combination for the low gear and a 52/14 combination for the high gear. This is a good gearing range for most couples in most circumstances.
Since being introduced to the tandem world, the Rohloff hub has evolved slightly, with a few structural changes. Most tandems now utilize the 36 spoke rear wheel (as opposed to the 32 spoke that was common in early days), hubs now have a reinforcing ring around the hub flanges (flange breakage was a bit of a problem with earlier hubs), and for hubs sold in the last couple of years the cog retention has changed from a threaded cog, to a carrier that incorporates a simple clip ring for cog retention, and finally to a new carrier with a threaded lock ring for cog retention (more on this later). Also, models are now available for use with thru axles.
How Shifting Works
Practically speaking, most Rohloff-equipped bicycles sold today have one of 5 different, common shifting mechanisms:
1) The Rohloff twist shifter and twist shifter light can be used on flat handle bars with MTB style brake levers, or on drop bars, placed at a bar end. This latter set up is not convenient, so it is no longer commonly seen.
2) The Co-Motion twist shifter can be used with drop bars and is popular. It is a durable and reliable shifter but its size (big and bulky) makes it a little challenging to use for some captains.
Co-Motion bar top twist shifter.
3) The Rohloff twist shifter and twist shifter light can be used on a Doohickey from R&E Cycles in Seattle. This allows use of the shifter with your choice of drop bars but does require reaching to the steerer tube to shift, an action some find inconvenient.
4) The Gebla Rohbox shifting system is an elegant solution that replaces the twist shifter and the normal Rohloff gear box with a set up utilizing modified brifters. Shifting can be done without moving off the brake hoods (very handy) but the Gebla system gives up the ability to shift multiple gears in a single throw (one or two gears per shift only) and it also lacks the numerical gear indicator present on both the Co-Motion and Rohloff shifters. It's nice to be able to look down and see what gear you are in at the moment. However, of all these systems, the Gebla most closely mimics shifting of usual chain and derailleur bikes with integrated brifters.
This is the silicone spray product recommended by Gates.
1) Keep them clean - Rinse with water or wash with water and mild soap, rinse and let dry. Spray with silicone spray.
2) Proper tensioning is not rocket science - We do not discourage you from using various special tools or phone apps to set belt tension, but in our experience, especially with the newer center track belts, these are somewhat superfluous. We find that if we push down with a finger on the center of the top run of the belt, using moderate force, the belt should deflect about 1/2". Too tight can introduce unneeded friction as well as excess bearing wear, while too loose runs the risk of belt slippage. We think too tight or too loose are reasonably obvious, without special tools or apps.
3) Take care of your belts - As noted, keep them clean. Avoid damage from sharp objects and make sure you use a snubber for the drive belt, if employed with a Rohloff hub. When packing/unpacking for travel, make note of belt handling instructions from Gates. We have a video on our website that goes over belt handling do's and don'ts.
Snubber in use with Gates drive belt and Rohloff hub.
Once again, Cycle Monkey is an excellent Gates belt resource.
They aren't for everyone. They wouldn't be the best choice for road racing. But on the whole we think the Rohloff Speedhub and Gates Carbon Drive are among the best technological advancements to enter the tandem cycling world in some time. We use ours almost every day and our belted Rohloff tandem has become our go to machine for travel. We're writing this during our Northwest winter (cold, wet, windy) and we haven' been on any other bike for months now. Try them - we think you'll like them.
Rohloff hub on Co-Motion Java.
Right seat stay on a Co-Motion Java Rohloff. The Torx head screw holds together the joint that allows the stay to be split for belt passage.
As for pros, we think there are many. To list a few:
1) Cleanliness - Gone are the days of chain ring tattoos, black greasy hands, and grease marks on hotel carpets/car upholstery.
2) Quiet operation - Chain noise is a distant memory.
3) Durability and longevity - No stretch, and depending on how long we live, maybe no replacement. Ever.
4) Ease of maintenance - Just rinse off with a hose, maybe clean with water and mild soap, rinse, let dry, and spray with silicone spray to repel dirt and water. And remember, no more dirty hands from chain grease.
5) Great for travel - Because the belts are so durable, they are great for travel.
By Mark and Chris Owings
If you've decided to purchase a bicycle with a Rohloff Speedhub, congratulations! You've made an excellent choice. Read on and perhaps pick up some useful pointers on riding with and caring for the hub. If you're still considering, read on and perhaps pick up information that will help inform your purchase decision.
Features of the Rohloff Hub
The Rohloff Speedhub 500/14 is a 14-speed, internally geared hub featuring a 526% range of gears, evenly spaced, with 13.6% increments between gears. The hub has been around for many years and has been increasingly used on tandems in the last 10 years or so.
The German-made hub has a reputation for reliability and durability, a reputation that is well deserved, in our view. Our personal experience with the hub comprises more than 8000 miles ridden on 3 different Rohloff-equipped Co-Motion tandems, including 7 international and 2 domestic tours, most of those involving air travel with the hub.
The Gebla Rohbox shifting system replaces the Rohloff external gear box with a proprietary one from Gebla. Color choices are silver (seen here) and black.
5) Finally, there is our current favorite shifting solution for the Rohloff hub, fairly new on the market. A Dutch company, Van Nicholas, now manufactures a split, drop-style handle bar that will accommodate the Rohloff twist shifter or twist shifter light. The twist shifter light fits the hand perfectly so when riding on the tops, no lateral hand movement is needed for performing shifts. Also, many captains find the physical effort needed to shift with the Rohloff product is less than required to shift a Co-Motion shifter.
The Rohloff twist shifter light mounted on Van Nicholas bars. This captain's current favorite set up.
Getting to Know the Rohloff Hub
Living with a Rohloff-equipped bicycle has pros and cons, and requires a bit of compromise on occasion. The hub is clean, durable, dependable, low maintenance, and requires no adjustment (all features, by the way, that make it very attractive for travel).
It does add cost and weight, compared to a chain and derailleur drive train. Comparing Co-Motion models, switching from a chain and derailleur drive train to the Rohloff and belts adds $1700 to the cost of the bicycle. According to Rohloff their system weighs some 220 grams more than a comparable chain and derailleur system; on our own bikes we've measured the increased weight at closer to 2 pounds.
Also, it takes considerable practice to learn smooth shifting under all conditions. Downshifting under load is especially different from a derailleur system; downshifts require a momentary let-off of pressure on the pedals, especially when shifting down from gear 8 to gear 7. In our experience, when traversing the gears down the range, as the troublesome 8 to 7 change is approached, it helps to double shift, ie: from 9 to 7 or from 8 to 6, thereby skipping the 8 to 7 trouble spot. In fact, I find myself double shifting often these days, in both directions.
There may be a small efficiency penalty with the Rohloff hub, when compared to a clean, well tuned chain and derailleur system. We suspect this is minimal in real life (Rohloff presents data on their website showing that efficiency is comparable between their hub and derailleurs). The seals on the hub do produce a small amount of frictional drag - when walking the bike this may cause the cranks to turn and heighten the perception of drag. However, in a very brief comparison we did of two Co-Motion Speedsters, equipped similarly and of identical weight, the Rohloff hub-equipped bike actually achieved a greater speed coasting down a measured incline than did the chain and derailleur-equipped bike. So, we think the issue of efficiency and drag is largely one of perception rather than significant reality.
You can quickly test your own hub to see if it is spinning freely, without significant drag. Put the bike in a work stand, or at least lift the rear wheel off the ground. With the hub in gear 14, turn the pedals to get the rear wheel spinning as fast as you can. Stop turning and hold the pedals still; the rear wheel should continue to spin at least 14 or 15 full revolutions before stopping. If it does, that means your hub does not have significant drag (in all likelihood it will spin many more revolutions than that!).
We suspect the perception of drag is enhanced by the noise the hub emits in some gears. Specifically, there is a faint, machinery-like noise coming from the hub in gears 1-7, which goes away entirely in gears 8-14. The noise results from the way the gears are engaged and becomes fainter with time, as the hub ages and breaks in. There may be a tendency to think the noise relates to drag, but this is not the case.
And we should mention what we think to be one of the biggest pros of the hub - the ability to shift while stopped. Just as chain grease and chain tattoos are past memories, so is being stuck in the wrong gear after an unexpected stop for a light or for traffic. Simply spin the shifter to the desired starting gear and off you go. Sweet!
Caring for the Rohloff Hub
Maintenance of the Rohloff hub is simple and easy. The hub and chain or belt should be kept clean from dust, dirt, and debris. Chain/belt and shift cable tension should be monitored and adjusted as needed. Periodically the gear box should be unmounted, cleaned, and a light coating of grease applied to the inner surface of the cable pulley. Hub lubricating oil should be changed every year or 5000 km. Hub oil change can be done by a shop, or is an easy home mechanic job. Oil change kits (cleaning oil, lubricating oil, syringe, tubing, new oil port plug) are readily available. Just make sure that whoever performs the oil change properly drains out as much of the old oil as possible, in order to avoid overfilling the hub. A bit of oil seepage from the hub seals is normal; an overfilled hub will leak more oil, especially when traveling by air. So, during the drain step in the oil change procedure, before adding new oil, it's best to let the hub drain overnight, if possible, to minimize the risk of overfilling.
Traveling with the Rohloff Hub
Here are a couple of travel tips we've picked up through experience over the years:
1) Oil seepage - Rohloff recommends that when transporting the bike the rear wheel be kept upright in order to lessen oil seepage from the hub. Well, for air travel that's not possible. When placing the rear wheel in the travel case, we pack rags around the hub and push thick pipe cleaners into the hollow axle ends, to catch any oil seepage. It helps if the hub is not overfilled in the first place (see above).
2) Brake rotor protection - For disc brake-equipped bikes we recommend that disc rotors be removed when packing the bike for travel, in order to avoid any potential rotor damage. This adds only a few minutes to the packing/unpacking process and is simple. in the case of the Rohloff rear wheel, on most but not all bikes, removal of the axle plate is necessary, to allow the rotor to slide off the hub. Again, this is a simple process. Procedures for rotor removal and reinstallation are on our website.
We think the Rohloff hub makes for an excellent travel bike, especially due to its durability and reliability. Also, there is no need for shifting adjustment, either when unpacking the bike or out on the road; it truly is a plug and play system. It's been years since we experienced the incessant fiddling with gear adjustment that so often characterized our travel with derailleurs.
Rohloff Hub Resources
Cycle Monkey, located in California in the Bay Area, is an excellent resource for all things Rohloff.
Several bicycle manufacturers have significant experience building bikes with the Rohloff hub. In the tandem world these include, but are not limited to Co-Motion, Calfee, Rodriguez, and Thorn. Co-Motion offers the Rohloff as a drive train option on several of their single and tandem bike models.
One part of the future has recently arrived already. Here's the background: when Rohloff hubs were becoming popular in the early years, the cog on the rear wheel threaded onto the carrier. Removal for servicing or replacement was difficult. Rohloff responded to complaints about that by switching over to a cog carrier that held the cog, now non-threaded, in place with a clip ring. Very quickly it became evident that in use these cogs rattled since they weren't held in place very tightly by the clip ring. The rattling noise drove tandem captains nuts. After what seemed to many of us users like a too long wait, Rohloff has now come out with what we think is an excellent solution, addressing troubles with both the prior two versions of the cog carrier; the carrier now secures the non-threaded cog by way of a threaded lock ring. We've been using this new carrier for about 1000 miles now and can attest to it being whisper quiet and very secure. The hardware necessary to make the change, for those bike owners with the clip ring set up, can be obtained through your local shop or from Cycle Monkey.
The new threaded lock ring cog retention system.
These days it seems any conversation about bicycles, including tandems, sooner or later gets around to the subject of e-bikes. Rohloff has jumped into the e-bike arena, in partnership with Bosch. They now offer the e-14, an electronic hub shifter, offered for the time being only on bikes equipped with a Bosch e-bike system (the shifter and Bosch motor share a battery). That's not to say that the Rohloff hub is not compatible with other e-bike systems, it's just that their electronic shifter only works with Bosch, for now anyway.
In the bicycle world this refers essentially exclusively to drive belts made by the Gates Corporation and offered as a part of their product line termed "Gates Carbon Drive", encompassing belts, pulleys, cogs, chain rings, and assorted accessories. The belts, available in a variety of sizes and configurations, are made of carbon fiber-reinforced polymer. They are familiar to tandem riders as a common replacement for timing chains, as well as a drive chain replacement on bikes with internally geared hubs. In our view, the belts really add value when paired with these hubs. We think, as Forrest Gump's mom might say, enclosed gear hubs and Gates belts go together like peas and carrots.
Pros and Cons
Are there any cons? We've heard that cost might be considered as a negative. However, when comparing expected lifespan to that of a chain, we think, depending on your annual mileage, a belt might prove to be a less expensive choice.
We've heard some riders say they shy away from belts because a belt might break and leave them stranded. In our experience this is an unlikely scenario, especially if the belts are treated properly. Nonetheless, sometimes, when we think of it, we carry a spare set of belts traveling, just in case. We've yet to use them.
Another issue that might be considered a negative by some, depending on stoker size, is that, given the limited lengths of timing belts available, the boom tube length on a tandem using a belt in place of a timing chain is fixed, thus fixing the stoker cockpit length.
Since the belt always remains a continuous, unbroken loop, special frame accommodation is required in order to install/remove the drive belt (not true for a timing belt). Manufacturers address this in slightly different ways, but mostly by means of a joint in a stay that is held by a bolt, screw, or coupler that can be removed to allow separation of the stay and passage of the belt. Some consider this a con; we do not. In our view this is an acceptable concession to the continuous loop feature of the belt and does not significantly lessen the strength or function of the frame.