absoluteBLACK’s Custom T-Lab Gravel Bike From Sea Otter

Update – We added noted some additional changes that Brandotti made to the bike since Sea Otter.

We’ve been holding onto this one for a little bit now until we were given the go-ahead to talk about everything on this custom T-Lab titanium gravel bike that was created for absoluteBLACK’s Tony Brandotti. If you had a chance to make it to Sea Otter, you might have seen it hanging around, but with a few different wheelsets.

The heart of the bike is the T-Lab titanium X3 gravel frame. While the T-Lab name might be on the newer side, you would have known the people behind it from Guru. The Montreal based bike brand has since moved from high-performance steel, titanium, and carbon frames to concentrate on just titanium with T-Lab.

The X3 uses specially shaped Grade 9 titanium tubing to create an incredibly stiff, yet light and comfortable bike that is able to handle just about any terrain. Asymmetrical chainstays and a BB86 bottom bracket make for efficient power transfer. Available in stock or custom geometry, Brandotti went with their cyclocross geometry over the gravel geometry to give it a racier feel. With disc brakes and generous clearance front and back, you can easily swap between 700c and 650b wheelsets, depending on your planned ride.

T-Lab customized the frame with adding the ability to run internal cable routing, though the mechanical bosses are still left to keep options open for the future. Fender mounts were also added for “when things get interesting” said Brandotti. The frame is finished with a mix of paint, bead blasting, and polished titanium, along with the absoluteBLACK logo along the top tube.

For the drivetrain, Brandotti went with Shimano’s latest Dura-Ace 9170 Di2 with hydraulic disc brakes and a 11-30 cassette. He swapped out the Shimano crank for Easton’s new EC90SL with matching black absoluteBLACK 48/32 subcompact rings. The EC90SL spider was designed around the previous generation Shimano bolt pattern, but the rings are compatible with both the current and previous generation Shimano bolt pattern. absoluteBLACK’s oval gravel rings are optimized to help improve climbing and increase cadence. The amount of ovalization is about 11% for the 48, and 8% on the 32, and they hit their peak size between 108 and 110.5 degrees. On the outter side, the cross hatch machining helps keep them extremely rigid, while reducing weight. On the inner side, machined chain guides keep shifting crisp. We’ve used them on the road, for cross, and for mountain biking, and you can definitely feel the difference in cadence when climbing and spinning on flats when you go back to standard, round road rings. For the off-road disciplines, the ovalization also helps with traction when you are climbing steep, loose terrain, which I am sure will also translate to gravel roads.

Kogel Bearings covers the bottom bracket and rear derailleur pulleys, both in gold. Both ends of the drivetrain use ceramic bearings, but the back end is what’s new. The pulleys use 12 teeth on the top, and 14 on the bottom. Unlike other oversized systems on the market, these pullies swap into the original cage instead of using a custom cage. The preproduction version uses a narrow/wide tooth pattern top and bottom, but production versions will only have the narrow/wide on the upper pulley. For now, they only work with Shimano Dura-Ace 9100, Ultegra 8000, and 105 5700 series  derailleurs, though they have standard size bearings available for older Shimano derailleurs, and other brands.

When it comes to the wheels, it was making its rounds on two different sets during the show. For the 700C, a set of Princeton CarbonWorks Wake 6560 disc wheels were mounted up tubeless with Schwalbe G-One Pro tires in 700×28. The Wake 6560 uses dynamic cross-section variability, or what looks like a bit of a wave pattern. The rim increases height to 65mm at the spokes and lowers to 60mm between them. The unique design was developed over a four year period and has been tested to be faster and lighter than offerings from Zipp. It also predates Zipp’s biomimicry design on the 454 NSW by a year.

For the 650b, Woven dropped in a prototype for their D35 Gravel+. An update to the D25 Gravel+, the new rim features an external width of 29mm, internal width of 22mm, and is 35mm deep. It’s a 24 spoke design front and rear, hand built with Sapin Laser spokes, laced 2-cross. They are also available as CX-Ray as an option, which is what Brandotti went with. You can also choose between 6-bolt or centerlock, and Shimano/SRAM, Campy, and XDR freehubs are available. For tires, the Woven were also set up tubeless with Schwalbe G-One Allroad in 650×40. Both wheelsets used Orange Seal’s Endurance Formula.

To round out the build, 3T and Prologo covered the cockpit and touch points. For the bars, Brandotti went with the Aeronova LTD in 42cm. We previously reviewed the Team Stealth addition, and I continue to use it on my personal road bike due to its comfort and shape. The 90mm ARX stem and Ionic 0 seatpost are also from the LTD lineup. For the saddle, he went with the carbon railed Prologo Dimension Nack. It’s 245mm long by 143mm wide and has a sizable cutout down the center to help relieve pressure on the sensitive areas. The OneTouch 2 tape uses the brand’s CPC technology to make the wrapped bars extremely grippy. The black/reflective colorway adds a nice touch to match the titanium frame, along with the functionality of reflective marks while riding.

With the 700c Princeton CarbonWorks wheels, the T-Lab weighs in at 16.85lb with crank boots.  Swapping in the 650b Woven wheels, which are filled with more sealant than their 700c counterparts, and the bike creeps up to 17.05lb.

Update – Brandotti has already been busy making some upgrades. In place of the stock headset, he added a Cane Creek AER II headset with 20mm of AER spacers, Robert Axle Project Lightning Bolt thru-axles (we have these and their trainer axle to test out on a Focus Mares), Shimano bar end junction box, and a host of items from Tune. The Komm Vor carbon saddle, GumGum Expander Plug with carbon top cap and screw, Leichtes Stueck seat post, Energietrager Di2 battery holder, and Wassertrager Uni bottle cages. With these changes, the bike should be down to less than 16.5 lbs.

Special thanks to Brandotti for the details and pics.