The X-Lab GT8 is a full carbon gravel race bike built for fast mixed-surface riding, long-distance gravel events, and riders who want modern gravel geometry without oversized price tags. It combines a Toray T-800 carbon frame, Shimano GRX Di2 1x12 drivetrain, integrated power meter crankset, in-frame storage, and clearance for up to 55mm tires—putting it directly against bikes like the Trek Checkpoint SL and Specialized Crux at a significantly lower cost.
Key Functional Details
- Toray T-800 full carbon gravel frame and fork
- Shimano GRX Di2 1x12 electronic drivetrain
- 10-51T cassette for wide-range climbing and loaded gravel riding
- Branta alloy crankset with integrated power meter
- Apple Find My anti-theft technology integrated into crankset
- Branta C45 Gravel carbon wheelset
- Continental Terra Trail 700x45c tires installed stock
- Up to 55mm tire clearance for larger volume setups
- Integrated in-frame storage with frame and fork accessory mounting points
- T47 threaded bottom bracket and UDH compatible rear dropout
- Claimed weight: 8.78 kg / 19.31 lbs (Size M)
Technical Specifications
| Frame |
XDS Carbon Frame, Toray T-800, UDH Compatible |
| Fork |
XDS Carbon Fork, Toray T-800, 100x12mm Thru-Axle |
| Stem |
Branta Carbon Stem |
| Handlebar |
Branta Gravel Carbon Handlebar |
| Seatpost |
XDS Carbon 27.2mm |
| Rear Derailleur |
Shimano GRX RD-RX717 Di2 |
| Shifters |
Shimano GRX ST-RX717 Di2 |
| Brakes |
Shimano GRX BR-RX715 Hydraulic Disc |
| Cassette |
Shimano CS-M6100-12, 10-51T |
| Crankset |
Branta Alloy Power Meter Crankset, 40T, Narrow-Wide, 24mm Steel Spindle, Apple Find My |
| Bottom Bracket |
T47 / 24mm |
| Rotors |
Shimano SM-CL700 Front 160mm / Rear 160mm |
| Chain |
Shimano CN-M6100 |
| Wheelset |
Branta C45 Gravel Carbon Wheelset, Stainless Steel Spokes |
| Tires |
Continental Terra Trail 700x45c |
| Saddle |
Fizik Terra Argo X7 |
| Claimed Weight |
8.78 kg / 19.31 lbs (Size M) |
| Sizes |
XS / S / M / L / XL / XXL |
Compatibility & Technical Notes
Good Fit: Riders looking for a fast gravel bike that can handle road speed, gravel events, bikepacking weekends, and aggressive mixed-surface riding. Strong fit for riders considering Trek Checkpoint SL, Specialized Crux, or Cervelo Aspero but wanting similar performance with a power meter included and more tire clearance.
Not A Fit: Not ideal for riders looking for a fully upright comfort-first geometry or flat-bar adventure bike. Not the best fit for heavy MTB trail riding where suspension and true MTB geometry are required. Not a fit for riders wanting a 2x front drivetrain setup from stock.
The GT8 ships as a 1x12 gravel drivetrain with a wide-range 10-51T cassette, which favors simplicity, chain retention, and climbing range over tight road cadence steps. The 55mm tire clearance is a major advantage for riders moving between fast gravel and rougher terrain. T47 threaded bottom bracket improves long-term serviceability, and UDH compatibility helps with derailleur hanger replacement and future drivetrain support.
Service / Ownership Context
This is the kind of gravel bike that works for both fast riders and newer gravel riders because the geometry balances stability and speed well. The included power meter removes a major future upgrade cost, and the in-frame storage plus accessory mounts make this much more practical for real gravel riding than many race-only platforms. For riders comparing value, this bike delivers high-end spec at nearly half the price of some direct competitors.
Fit & Use Signals
- Best for gravel racing, adventure rides, long mixed-surface routes, and fast weekend group rides
- Good for riders who want one bike that can handle road and gravel without compromise
- Excellent for riders upgrading from aluminum gravel bikes into full carbon performance builds
- Strong value versus Trek Checkpoint SL7 and similar premium gravel platforms
- Good beginner gravel geometry with enough stability for confidence and enough speed for serious riders
The hidden value here is the included power meter and real gravel tire clearance. Many bikes in this category force customers to spend another $800 to $1,500 later for power meter upgrades. The 10-51T cassette also matters more than most buyers realize—it makes steep gravel climbing and loaded rides much easier while keeping the drivetrain simple. T47 bottom bracket is a mechanic win because it is quieter and easier to service than many press-fit systems. Biggest buying mistake is underestimating tire size strategy: customers often buy this for fast gravel but later realize they want bigger tires for rougher terrain, and this frame supports that move. Strong upsells include tubeless setup optimization, frame bags, computer mount, pedals, and bike fit.
