Surly Krampus 29+ Mountain Bike with Suspension Fork, Rohloff SPEEDHUB500/14, and Gates Belt Drive

Sometimes the team here at Cycle Monkey dreams up a project that is not specifically for a customer but rather to satisfy our own curiosity. We chalk it up to product research, but these projects also have a bit of a selfish motivation: we like to build cool bikes! We put together this Surly Krampus to showcase in the Rohloff booth at the Interbike trade show in Las Vegas last September. The various customizations on this build were very popular at the show and prompted plenty of people to stop by and marvel at the Rohloff hub, belt drive, and suspension fork we had installed on the frame. 

The goal for this build was to create a bike that could be ridden more aggressively through rock gardens, off drops and jumps, and down steep descents. Surly’s Krampus comes stock as a fully rigid 29er with large volume tires that can care of some of the harsh bumps found on trails. Its three inch wide tires on 50mm wide rims provide a fair amount of pneumatic suspension, but in certain situations, the bike is very clearly rigid.

Nirve Switchblade Chopper Rohloff Conversion

This Nirve “Switchblade” chopper, styled after a classic motorcycle, is one of the more unusual bikes we've had in for a Rohloff conversion. We have experience installing Rohloff hubs on almost every type of bike, but this was a new one for us. The goal was to give this extremely relaxed, comfortable bike the low gearing to pedal up and over more hills.

The owner of this bike lives in San Francisco and uses it to cruise around the waterfront and flatlands, but he also wanted to be able to pedal up some of the city’s many steep hills. The bike had come with a three speed coaster brake hub, but he wasn't satisfied with its limited gear range. He also has a trailer that he uses often to carry groceries and gear, so he wanted a durable drivetrain that would be strong enough to haul plenty of weight.

Our customer bought this bike in part because he likes the classic styling but more importantly because he likes how comfortable and relaxed it is to pedal. The chopper puts you in a very leaned-back seating position, with the cranks and pedals far in front of you and the handlebars very high in the air. The one limiting factor, however, is getting up hills in this seating position.

The Rohloff SPEEDHUB has the largest gear range of any internally geared hub on the market and is an ideal choice for this style of bike. Since the geometry of the bike doesn't allow you to stand up and crank hard on the pedals, climbing hills is easiest with a low gear and steady pace. The SPEEDHUB gives you a 526 percent change in gearing across 14 gears, ensuring a very low and very high gear to get over all kinds of terrain.

For the wheel build, we laced a silver SPEEDHUB up to a 24 by 3 inch aluminum rim, designed to fit larger volume tires for a comfortable ride. For the front wheel, we used a larger 26 by 2.5 inch rim on a silver Schmidt SON 28 dynamo hub. We hooked up the generator hub to a Busch & Muller Lumotec Classic front light, giving him plenty of battery-free lighting for night time cruising.

We had to make a few adaptations to the stock setup in order to make the rear wheel compatible with the chopper frame. Because the frame was based around the use of a coaster brake hub it did not have any brake mounts, either disc or rim. Rohloff does not offer a coaster or drum brake hub option, so we needed to install brake mounts of some kind. Our customer found and brought us a special disc brake mount adapter that is installed around the hub’s axle and is secured to the dropout.

Once the brake issue was settled, we used the Rohloff long torque arm to anchor the hub’s torque input to the frame. The cable routing was a bit unusual due to the orientation of the brake mount and the shape of the frame. We had loop the brake and shift cables backwards around the dropouts instead of running them along the chainstays.

A variety of leather and chrome components give this bike a classic chopper appearance. A leather Brooks saddle, grips, and front fender mudflap match the leather handlebar bag. A chrome handlebar and polished stem match the silver wheels we built. The spiked silver Tioga Spider pedals finish off the bike's look.

The bike now offers the gear range needed to pedal around San Francisco while still maintaining the unique chopper style our customer was after. When he came to pick up the bike, he was very pleased with the new-found range the SPEEDHUB gave him. He said he was excited to ride around the city on a much more regular basis. If you want to do a Rohloff conversion on your own bike, contact us to discuss the details!

Build Details:

• Frame: Nirve Switchblade

• Fork: Nirve 

• Headset: Chromed steel

• Stem: Polished aluminum

• Handlebar: Chromed steel chopper bars

• Shifter: Rohloff

• Grips: Brooks Plump Leather

• Seatpost: Chromed steel

• Saddle: Brooks B66

• Seat Clamp: Nirve

• Front Hub: Schmidt SON 28

• Rear hub: Rohloff SPEEDHUB 500/14

• Spokes: Sapim Race

• Nipples: Sapim Brass

• Rims: Wide chopper

• Tires: Innova 24x3.0 rear, Innova 26x2.5 front

• Cranks: Race Face Turbine

• Pedals: Tioga Spider

• Bottom Bracket: Race Face Turbine

• Chain ring: Surly Stainless Steel

• Chain: Wipperman Connex 7R8

• Brakes & Levers: Tektro 319A BMX brakes, Avid BB7 MTN calipers

• Rotors: Magura Storm

• Extra: Busch & Muller Lumotec Classic front light, Busch & Muller 4-D Lite Plus tail light, chain guard, fenders, handlebar bag

Independent Fabrication Rohloff-Equipped Custom Touring Bike

Matte black Independent Fabrication "Independence" frame
customized with S&S couplers and Rohloff-specific cable routing.

Independent Fabrication is known for building beautiful, eye-catching bikes and this matte black touring frame, although understated, is no exception. We built this custom “Independence” model for a customer who lives in Thailand and has done plenty of off road touring throughout Southeast Asia on his trusty mountain bike. Although his old bike had served him admirably, he had been dreaming up the ultimate touring bike based around the Rohloff SPEEDHUB 500/14 for years. He wanted his new ride to last him for the rest of his life, so the SPEEDHUB was the perfect shifting system for his needs.

Initially this customer had been interested in a Surly Troll frame, which is a very popular model for off road touring. However, he wanted S&S couplers to make the bike easier to travel with. That would have required us to send the frame to a frame builder for modifications and then to a powder coater to have it repainted. After considering his options, he decided to go with a custom frame to get all the features he wanted in one complete package.

Sliding dropouts make for easy chain tensioning.

Twenty2 Cycles Belt Drive Rohloff 29+

This eye-catching Twenty2 Cycles 29+ is custom-built for adventure touring but is also well suited for fast singletrack.

This gorgeous Twenty2 Cycles frame is the latest in a handful of builds we have put together using the new “29+” platform. These bikes use three inch wide 29er tires mounted to 50mm rims, which provide ample float and traction like a fatbike, yet roll fast like a standard 29er. The “29+” bike designation was invented by Surly Bikes with their release of the Krampus model last year, and it has proven popular for bikepacking as well as fast singletrack riding.

Our customer for this bike had owned a Rohloff hub for years, and it has been serving him reliably on his Surly Long Haul Trucker touring bike. When he decided he was ready to start exploring off road, he knew a Rohloff was in the cards for a new mountain bike build as well.

Rohloff-Equipped Soulcraft Road Bike

Custom Soulcraft frame in sea-foam green.

We built up this custom Soulcraft for a customer who had a very specific road bike in mind. He had searched in vain for a production frame to suit his needs, but couldn't find anything available on the market. After deciding that a custom frame would be his best option, he contacted Soulcraft, a local Northern California framebuilder, to make his dream bike a reality. With his one-of-a-kind frame in hand, he came to us to build up the rest of the bike around the Rohloff gearing system.

Our customer was looking for a comfortable yet nimble road bike that he could take on all-day rides without straining his neck, back, or shoulders. He requested a taller headtube on the frame to give him a slightly more upright seating position, yet he still wanted it to have a quick-handling ride quality like a traditional road bike. He also knew that he wanted to use a Rohloff SPEEDHUB 500/14, so the frame was made specially for the hub – braze-ons for Rohloff cable routing, no derailleur hanger, and a sliding dropout with a bolt for an axle plate to secure the hub's axle in place.

Rohloff SPEEDHUB 500/14 with Rohloff-specific dropout design.

Because our customer likes to go for long road rides, he knew the Rohloff SPEEDHUB would work well for his riding style. The internally housed mechanics of the shift system are extremely durable and only need to be serviced with a new oil bath once a year. Long rides normally take you miles away from any bike shop, so a reliable shift system is a priority for endurance riding. Knowing he did not want to be stuck mid-ride on a desolate country road with derailleur problems, our customer figured the SPEEDHUB was the perfect hub for his needs.

We have long believed a wheelset truly “makes” the ride. Wheels play a large part in the ride quality and general feel of any bike. Much like a custom frame is tuned for a given rider, custom wheels can be tuned the same way. For the wheels on this bike, we used Velocity’s A23 road rims because the wider footprint allows the tire to spread out more, providing more comfort, control, and traction. We used White Industries’ American-made MI5 front hub and the SPEEDHUB on the rear. The polished silver color of the rims and hubs matched perfectly, making for quite a shiny, vintage-looking wheelset.

White Industries is another local company we have come to trust. They have been making parts in Northern California for nearly 40 years, and have a reputation for very precisely machined components. For these reasons, we chose a White Industries crankset, bottom bracket, and chainwheel for the Soulcraft.

Nitto Classic handlebars.

Finally, we set up the cockpit. We chose Nitto’s classically shaped drop bars, paired them with a Nitto stem, and mounted the Rohloff shifter on the end of the bar with a Hubbub adapter. Lastly, we wrapped the bars in tan Deda tape to compliment the Gilles Berthoud leather saddle.

This custom frame was a joy to build, and we were excited about the Rohloff-specific features designed into the frame. We expect our customer will enjoy this no-frills, durable road bike for years to come. Contact us to discuss whether a Rohloff-equipped road bike is in your future.

Build Details:

•  Frame: Soulcraft custom steel road
•  Fork: Soulcraft steel
•  Headset: Chris King NoThreadset
•  Stem: Nitto UI85EX
•  Handlebar: Nitto Classic
•  Shifter: Rohloff
•  Bar Tape: Deda
•  Seatpost: Paul Component Engineering Tall and Handsome
•  Saddle: Gilles Berthoud leather
•  Front Hub: White Industries MI5
•  Rear hub: Rohloff SPEEDHUB 500/14
•  Spokes: Sapim Laser
•  Nipples: Sapim brass
•  Rims: Velocity A23
•  Tires: Schwalbe Durano Plus
•  Cranks: White Industries VBC Road
•  Bottom Bracket: Phil Wood Stainless
•  Chainring: White Industries VBC
•  Pedals: Shimano Ultegra
•  Chain: Wipperman 8sX
•  Brakes: Shimano Dura-Ace
•  Levers: Shimano R600