Split Belt Pro Tour: Sage Bike Build

Bike Build:

Sage Titanium Barlow Featuring VEER Split Belt Pro

Veer’s creative director, Kayla Lopez, geared up for a 7 day, 360+ mile bikepacking trip with longtime friend and fellow touring enthusiast, Francie C.

Kayla loves gear (a lot!) and as the tour wrapped up, we thought we’d give you some info about the most important gear of all, the bikes. We’ll go through the bike’s technical setup, why we chose parts and configurations, what we struggled with, and of course, retrofitting the bikes with the Split Belt Pro Drive.

Heading straight through the heart of Oregon, following almost entirely gravel roads, Kayla chose to build up a Sage Titanium Barlow. Beyond the fact that this is one good looking raw titanium frame with a carbon Enve fork and Chris King Headset, this bike is from Oregon. That of course means good juju for its maiden voyage. We started this build with the frameset and bottom bracket only, adding all remaining components to form the build shown here:

  • Sage Titanium Barlow frame
  • VEER Split Belt Pro conversion kit. Composed of 30T rear Rohloff cog, 72T front ring for 130BCD 5-bolt cranks, and tensioner
  • Rohloff 500/14 CC DB OEM2 internally geared hub
  • Shimano Ultegra front wheel with 12mm hub and splined rotor mount
  • Carbon Enve fork with 12mm through axle and flat mount brake standard
  • Chris King Headset
  • Shimano XT brakes/Ultegra (I’ll explain)
  • FSA Mega Evo Bottom Bracket
  • Sram GX Cranks
  • Clement X’plore m50 700C x 40 tires
  • Shimano SPD Pedals PD-M530
  • Easton stem
  • Velo Orange Crazy Bars
  • Ergon GP1 grips
  • Brooks Leather saddle

Rohloff Might Roll Off the Frame

The Rohloff is renowned for its durability, ruggedness, and is essentially bullet proof. With some big climbs on the trail, the wide 526% gear range and low gearing achieved with 14 speeds is pretty enticing. Paired with our Split Belt Drive, it’s one of the best combinations for robust bikepacking. Unfortunately, the hub we had available for this trip was pulled off a previous build utilizing a 135mm wide quick release axle model. The Sage Barlow has a 12mm rear thru-axle and well, that made things a little tricky for us. Long story short, I spent several hours lathing out a few fancy pieces of aluminum to adapt the QR model to the thru-axle dropouts. Maybe a little excessive, but it kept things rolling. Rohloff does make a 12mm thru compatible hub. We highly recommend you match your hub to your frame in the first place. 

 

 

Split Belt and Split Standards

One of the primary goals of this tour is to show the world that VEER’s Split Belt can be fitted on a bike without a split frame and can hold its own in some rugged conditions. We have come a long way with our technology and gone through countless iterations to be able to achieve this.

One of the hardest challenges we face is making sure that the belt has a straight path from the front ring to the rear cog without the belt or either cogs running into anything. This means standards are our friends. The only problem is that we have WAY too many friends. We’re working with three different crank spider sizes (130 BCD 5-bolt, 110 BCD 5-bolt, and 104 BCD 4-bolt) and four primary internally geared hubs (Rohloff, Alfine, Nexus, and Enviolo). All these components have unique chain lines, measured from the frame center to the sprocket center. Sometimes chain lines vary between hub model and year. Don’t even get me started on bottom bracket and crank spacing. This is a very short list of the challenges we are facing making belts fit into a chained world. But we love belts! So, it must be done.


The most common and variable issue we have is the front ring running into either the chain stay or the cranks as we try to achieve a straight belt line to the internally geared hub. The Rohloff has its chain line relatively far from the center of the hub. This means there’s less likelihood of the front ring running into the chain stay, but a higher likelihood of the front ring hitting the cranks. For this reason, we offset the teeth of the rear cog inward a few millimeters to bring that beltline into a more neutral area. This coupled with the relatively narrow chain stay of the Sage and the somewhat liberal flaring out of the SRAM GX crankset gave the belt ample room. With the addition of some 1mm spacers to the inside of the belt ring we had the perfect beltline. Having your belt line dialed to +-1 mm is important to ensure even force distribution on all the carbon strands within the belt and uniform wear on the sprockets.  


Once the front and rear rings were installed, we simply needed to add the belt tensioner and the belt itself.

The Sage has a thru-axle, which usually means no adjustability in the horizontal direction for tensioning the belt (such as slotted dropouts). That’s where our Split Belt Pro tensioner comes in. The tensioner takes up slack near the rear sprocket and keeps the belt from riding up the teeth/skipping, even at relatively low belt tension. The tensioner simply screws into the derailleur hanger of the bike and can be adjusted by hand into position. 

The final step was simply running the spliced belt through the rear triangle and fastening the two ends of the belt together along the “V” cut splice. Inserting the stainless steel pins through the belt and riveting the ends with our Riveter went smoothly. The belts are custom cut to length according to your chainstay dimension, so the fit was perfect.

 

Brakes Be Breaking My Back

The Sage Barlow is an adventure/gravel bike designed to the tee. This means it was meant for drop bars and hydraulic brakes, but we wanted to do a few tweaks. To accommodate the Rohloff twist grip shifter, provide more room for bar bags, and improve control on descents, we decided to go with flat bars. This proved to be a little tricky.

Hydraulic brakes on road and gravel bikes have a different mounting standard than that of mountain bikes. Mountain bikes either have IS mounts or the more recent post-mount standard. The Sage and other gravel bikes have what’s called “flat mount” brakes. Flat mount brakes are designed to fit the rear brake between the seat and chain stays, usually with a 140mm brake rotor. Because the Rohloff doesn’t accommodate rotors smaller than 160mm we decided to get a caliper adapter that took us from flat mount 140mm to post mount 160mm. This failed tragically.

The adapter and caliper simply didn’t fit between the chain and seat stays. We eventually decided to purchase a Shimano flat mount Ultegra caliper and pair it a little awkwardly with an XT mountain lever. This allowed us to use flat bars and buy a simple 160 mm flat mount caliper adapter to accommodate the Rohloff 160mm rotor. However, this meant we had to bleed the brakes and buy a new brake line. Fortunately, there was no issue mounting an XT brake caliper to the Enve fork with the flat mount to 160mm post-mount caliper adapter. All of this for flat bars… But hey, we made it happen, and with minimal foul language.

The other slog this rear flat mount caliper standard caused was difficulty preventing the Rohloff from rotating under load. Internally geared hubs need a way to fix the rotation of the axle to the frame, because the axle acts as something for the planetary gears to “push” against as they rotate the wheel in overdrive or underdrive gears. The hub on this build utilizes an OEM2 axle plate, which fixes rotation to the brake caliper mount. We much prefer this method to the standard, somewhat universal Rohloff torque arm that you clamp to your chain stay. Unfortunately, there is currently no OEM2 bracket that works with flat mount brakes as of this writing. 

Our friends over at Cycle Monkey are working on an adaptor but we couldn’t wait… so we made our own. It utilizes the 160mm brake caliper bracket but adds an extension for the OEM2 axle plate to seat against. This is a simple part but difficult to fabricate, so we’d recommend using the standard torque arm if you are running a Rohloff in conjunction with flat mount brakes (until the more elegant solution is released).

Sweeping Down Roads with Some Sweep Bars (kinda)

Remember how I said we were mounting up some flat bars? Flat bar is a loose interpretation here. Kayla has opted for some “alt” bars that are a unique combination of sweep bars (for a more ergonomic riding position and improved steering stability) and bull horns (for climbing and for a more aerodynamic road position). The center portion of the bars replicate the “tops” of a drop bar as well. You get a little bit of everything with these suckers. Unfortunately, these bars only come in a 25.4mm diameter, an old MTB size, which means you must have an adapter to use them with a 31.8mm stem. 


And Tonight They Head North

Kayla and Francie will be headed to Mt. Shasta, California tonight and hitting the trail out of Klamath Falls, Oregon tomorrow. Stories comparable to those of leaving the shire will inevitably be told upon their return. Although we’ll be hearing them over a few beers, we hope you’ll indulge in them with us through our blog, social media, and awesome photos (they’re both photographers). Get Veered!


Words: Daniel Hacking

Photography: Kayla Lopez 

 


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