Factor AlutovsOstro Gravel

Factor usually builds surgical tools for specific races, and the Ostro Gravel is exactly that: a "fish filleting knife" designed for winning on fast fire roads. It mirrors the Ostro VAM road bike so closely that it’s UCI-legal for road racing and is meant for the pointy end of a World Series event. The Aluto behaves more like a "chef’s knife," taking much of the Ostro’s speed and adding actual utility for the other 95% of gravel rides. It introduces a storage hatch in the downtube and swaps deep aero-at-all-costs tubing for slender profiles reminiscent of the O2 climbing bike. While the Ostro Gravel focuses on cheating the wind at high velocities, the Aluto targets a "bright" and lively ride quality that feels less specialist. The Ostro is strictly electronic-only and heavily integrated, whereas the Aluto keeps things slightly more sensible with a round steerer and a Universal Derailleur Hanger. Both are high-end carbon frames that lean toward the "fast" end of the spectrum, but they diverge sharply when the road surface deteriorates or the ride duration exceeds a few hours.

Riding the Ostro Gravel feels like being shot out of a cannon on smooth fire roads, but the frame is brutally stiff. If you hit anything remotely technical or chunky, the rear end provides almost zero compliance, making it hard to keep power down through the chatter. It is a taut, lithe, and responsive machine that demands an experienced pilot to handle its rigid feedback on long days. In contrast, the Aluto offers an eager, light turn-in that belies its stock 45mm tires, feeling much more at home on mixed-surface loops where agility matters more than raw aerodynamics. The handling on the Ostro can be a handful in tight singletrack due to its road-derived geometry, occasionally requiring significant body English to coax it through corners. The Aluto’s 72-degree head angle and 423mm chainstays (size 56) keep things feeling intuitive and road-like without the jarring consequences of the Ostro’s aero-optimized tubes. While the Aluto front end isn't soft, it lacks the stolid, over-stiff character that reviewers found fatiguing on the Ostro. On the road, the Ostro Gravel effectively doubles as an endurance bike, provided you can stomach the firm rear end. The Aluto handles road sections with even more grace, skipping over broken pavement rather than thudding through it. For technical descents, the Aluto’s lower bottom bracket provides a lower center of gravity that inspires more confidence than the high-and-mighty stance of the Ostro.