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Surly Big Dummy Cargo Bike with Rohloff SPEEDHUB, Schlumpf Speed Drive, and S&S couplers

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When a customer told us he was planning to tour through Europe on a cargo bike, we knew we were in for a fun and unique project. Cargo bikes are perfect for hauling plenty of gear, but can be cumbersome on long distance rides or hilly terrain - not to mention a challenge to get through an airport. While our customer was not concerned with riding fast, he said he wanted a cargo bike that was comfortable, durable, and versatile enough to get him and his gear across a continent. The whole bike needed to easily pack up to fit on planes and trains, and would also serve as his daily commute vehicle when he returned from his trip. After a few conversations with our customer about his needs, we set to work planning out a build that would meet his criteria. His unique riding needs were a natural fit for a Rohloff SPEEDHUB 500/14 internal gear hub and Schlumpf Innovations Speed Drive two speed internal crankset, which together provide a reliable, wide gear range drivetrain that is perfect for hauling heavy loads across long distances.



Taking into account the longer distances and larger loads our customer would see on his tour, a strong steel-framed cargo bike that felt stable under load seemed like the best choice. We ruled out a front loading cargo bike because the smaller diameter front wheels are less comfortable on bumpy roads and less stable at higher speeds. Instead, we chose Surly’s Big Dummy"long tail" cargo bike. Long tail designs place the rear wheel farther back behind the rider to allow more room for cargo. They typically use the same size wheels on both ends and handle much like a standard bike. Like all of Surly's frames, the Big Dummy is strong, affordable, and well-designed. It has a large deck over the back wheel and roomy bags hanging from the sides that can carry many items a standard bike cannot. An optional center-stand is also available to keep the extra weight from tipping the bike over. Optional add-ons like side rails, a third wheel side car, cushions for the back deck, foot rests, and child seats allow the Big Dummy to haul all manner of people, lumber, camping gear, building supplies, furniture, or even other bikes.

Once the Big Dummy frame arrived, we sent it to a local framebuilder to have S&S couplers installed on the top tube and down tube. Our customer was concerned that the extra-long bike would not easily fit on the plane to Europe or onto trains during his trek. With travel couplers about halfway through the length of the bike, it packs into roughly the same volume as a normal-sized bike. After the couplers were installed, we took the frame and kickstand body to a powder coater for a slick matte gray finish. We also sent nearly all the silver aluminum parts to a local anodizer for a stealthy black finish, including the cargo rails on the frame and kickstand legs.



When a rider is hauling a heavy load even moderate hills are challenging, so cargo bikes need to be equipped with very low gears. Most cargo bikes are outfitted with a triple-chainring mountain bike derailleur system and wide range cassette to allow for the easiest hill climbing gear. Although these bikes can reach the low gears needed, a rider still has to pedal very hard because of the extra weight. With this amount of load being put into the drivetrain, it is not uncommon for a rider to snap a chain or bend a derailleur when cranking hard up a steep hill on a fully loaded cargo bike. The SPEEDHUB is strong enough to handle exceptional amounts of load while still offering the same low gear as a mountain bike derailleur system. This makes it an ideal drivetrain option for the demands of cargo bikes.

Perhaps just as importantly, the SPEEDHUB can shift into any gear at any time, meaning a rider doesn’t have to be pedaling to change gears. This is an advantage on cargo bikes that take a while to get up to speed. A rider can downshift at a stoplight, for example, and be ready to accelerate when the light changes. Or, if the rider runs out of steam on a hill and takes a break, they can easily shift and resume pedaling. On a derailleur-equipped bike, riders must anticipate a stop and downshift before they come to a full stop in order to be able to easily accelerate again.



In addition to the SPEEDHUB, we also installed a Schlumpf Speed Drive two speed internal crankset to make the gear range even wider. The Schlumpf crankset features buttons on either side of the crank spindle to switch between the high and low gears. The two gear options are made possible by a planetary gear unit within the crankset. A rider simply taps the button on the right side with their heel to switch to a higher gear, then taps the button on the left side to switch back to a lower gear. 

Although the SPEEDHUB offers enough gear range on its own for most cargo bikes, pairing it with a Schlumpf Speed Drive offers the range needed for the type of varied riding our customer would be doing. The Speed Drive features a 1.65 overdrive ratio, which effectively allows for four additional gears on top of the SPEEDHUB's 14. When combined, the SPEEDHUB and Schlumpf system offer an incredible 868 percent change across the entire range of gears.

To keep the chain tensioned properly, we installed a chain idler kit from Terracycle. Mounted on the diagonal tube of the frame, the chain tension changes as the idler slides up or down the tube. We prefer this setup over a chain tensioner because the long chain on these bikes tends to bounce around on rough surfaces and hit the frame, causing paint damage and noise.



To make the bike as durable as possible and ensure our customer wouldn’t be stranded on his tour, we built up a sturdy wheelset that would be nearly impossible break in normal riding conditions. We selected Velocity's Cliffhangers, which have 15 percent thicker walls than most other rims, and laced them to a black SPEEDHUB in the rear and a black Schmidt SON 28 dynamo hub up front using Sapim Force spokes and brass nipples.Lastly, we mounted Schwalbe’s flat resistant Big Apple Plus tires to the rims with Slime's self-sealing tubes.

The dynamo hub will provide battery-free lighting for long riding days that stretch into the night. The generator hub was paired with a Busch & Mueller Luxos U front light and Seculite rear light. The Luxos U light has a handlebar-mounted on/off button with a USB plug for charging phones, GPS units, and other electronic devices.



A variety of comfort-oriented components for the seating and cockpit areas ensure the bike will not become painful during long days in the saddle. Jeff Jones H Bars have plenty of backsweep and multiple hand position options, road bike bar wrap on the handlebars improves grip and comfort, Ergon GC1 grips feature an ergonomic palm rest, and Selle Anatomica’s Titanico leather saddle flexes with a rider’s pedal stroke and breaks in to become more comfortable over time.

This bike had many extras to handle its unique intended uses. An Ortlieb handlebar bag, Surly framebag, and front rack allow even more gear than the longtail deck and side bags alone. Full coverage fenders will keep our customer clean and dry on wet days, and rear-view mirrors will keep him safe on the road. An Abus Bordo Granit X-Plus lock is mounted on the frame to keep the bike secure when it’s parked. 

When our customer received the bike after we shipped it to him, he was very pleased with the finished product and is now looking forward to his tour even more. If you’re considering a Rohloff-equipped cargo bike of your own, contact us to see what we can put together for you.

Build Details:

• Frame: Surly Big Dummy with custom S&S couplers
• Fork: Surly Big Dummy
• Headset: Chris King
• Stem: Thomson Elite X4
• Handlebar: Jeff Jones H-Bar
• Shifter: Rohloff
• Grips: Ergon GC1
• Seat post: Thomson Elite
• Saddle: Selle Anatomica Titanico X
• Seat Clamp: Surly
• Front Hub: Schmidt SON28 disc
• Rear hub: Rohloff SPEEDHUB 500/14
• Spokes: Sapim Strong
• Nipples: Sapim Brass
• Rims: Velocity Cliff Hanger
• Tires: Schwalbe Big Apple Plus 26x2.0
• Cranks: Schlumpf Innovations 175mm
• Pedals: Time ATAC DH4
• Bottom Bracket: Schlumpf Innovations Speed Drive
• Chain ring: Schlumpf Innovations 34 tooth splined
• Rear Sprocket: Rohloff
• Chain: Wipperman 9sB
• Brakes & Levers: Avid BB7
• Rotors: Avid front, Rohloff rear
• Extras: Revelate Designs/Surly Frame Bag, Xtracycle bags, Xtracycle wide loaders Ortlieb Ultimate 6e handlebar bag, Abus Bordo Granit X-Plus lock, Planet Bike Cascadia fenders, Terra Cycle Dummy idler, Surly front rack, Mirrycle mirrors, Busch & Muller Luxos U front light, Busch & Muller Seculite rear light.


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