Factor O2 VAM
Climbers who want Factor. Ostro if you also care about aero.
Factor's lightweight race bike. Less aero than Ostro, still a low race fit.
Climbers who want Factor. Ostro if you also care about aero.
Factor's lightweight race bike. Less aero than Ostro, still a low race fit.
CX racers. If you want gravel capability, look at Checkpoint or Checkmate instead.
A UCI cyclocross race bike with IsoSpeed on some generations. Tight, muddy, and built to be shouldered — not a Checkpoint with CX tires.
Climbers and riders who want a light Specialized that isn't a full aero race bike. Not an endurance bike.
A lightweight road bike without the Tarmac's aero brief. It climbs and floats; it does not try to be a Tarmac SL7 in a crosswind. The position is still race-adjacent, not Roubaix-tall.
| Measurement | ![]() FactorO2 VAM 2025 | ![]() TrekBoone 2022 | ![]() SpecializedAethos 2022 |
|---|---|---|---|
| Stackmm | 565 | 583+18 | 565 |
| Reachmm | 388 | 394+6 | 387−1 |
| Head tube angle° | 73.3 | 72.0−1.3 | 73.5+0.2 |
| Seat tube angle° | 73.2 | 73.5+0.3 | 73.5+0.3 |
| Chainstaymm | 405 | 425+20 | 410+5 |
| Wheelbasemm | 993 | 1038+45 | 991−2 |
| BB dropmm | 70 | 66−4 | 72+2 |
| BB heightmm | — | — | — |
| Standovermm | — | — | — |






| Part | O2 VAM 56 | Boone 56 | Aethos 56 |
|---|---|---|---|
| Stem | 100 mm | 100 mm | 100 mm |
| Bar | 420 mm | 420 mm | 420 mm |
| Crank | 172.5 mm | 172.5 mm | 172.5 mm |
The Trek Boone 5 Can Tackle the Toughest 'Cross Races ... With a carbon frame built to absorb shocks, the Boone can crush cyclocross races, smooth the roughest ...
Trek's recently launched Boone introduces new frame shapes, new cable management and thru-axles, but most importantly its proprietary IsoSpeed decoupling ...
Step forward the Specialized Aethos. I reviewed this thing in the Pro model and I was rather smitten. The ride is sublime, the weight for a disc brake road bike ...
It's reliable, intuitive and offers sensible gearing ratios that allow extensive range without big jumps. Specialized Aethos Comp. (Image credit: Future). I ...