Factor LSvsSpecialized Crux
The Factor LS has a 1005mm wheelbase in a size 54, which is shorter than many endurance road bikes. While the LS feels like a widened road racer, the Specialized Crux uses Aethos-inspired engineering to hit a frame weight of just 725g. These machines strip away the typical gravel baggage of mounts and suspension in favor of pure speed.
Overview
Both bikes ignore the trend of turning gravel bikes into drop-bar mountain bikes. Specialized and Factor chose to build road bikes for the dirt, but they arrived there from different ends of the workshop. The Factor LS is a carbon copy of the company's O2 road racer widened for 43mm tires, while the Crux is an ultralight cyclocross evolution that stole the engineering playbook from the featherweight Aethos road bike. You won't find Future Shock or integrated frame storage here. Factor sticks to a traditional road silhouette with a 27.2mm round seatpost and a stiff, reactive frame. Specialized is even more minimalist, using external seat clamps and traditional round tubes to hit record-breaking weights. If you want a bike to carry racks for a month-long trip, look elsewhere; these are for finishing a race as fast as possible or winning the local groad group ride.
Ride and handling
The Factor LS handles with the precision of a criterium bike. It dives into corners with a 59mm trail figure that makes it one of the twitchiest gravel bikes on the market. Reviewers noted it feels like a well-balanced road bike with fat tires, which is great for dodging potholes at speed but can feel skittish on steep, loose descents. It rewards aggressive inputs and feels exceptionally efficient, though that stiffness becomes unapologetically jarring on choppy singletrack. The Crux is a different kind of animal—playful rather than just sharp. Because it is so light, you can flick it over obstacles with minimal effort, a trait BikeRadar compared to a Bucking Bronco. It is slightly more stable than the Factor due to a longer wheelbase and more trail, yet it still feels alive on technical climbs. While the rear end is relatively comfortable thanks to a flexing Alpinist seatpost, the front end can be harsh; testers experienced exaggerated vibrations through the thin fork blades on very rough terrain. Climbing is where these two really fight. The Crux is a mountain goat that makes steep grades feel almost effortless, whereas the LS uses its massive bottom bracket stiffness to translate every watt into forward motion. The Factor feels more planted on smooth dirt, while the Crux feels like it is dancing over the top of the gravel. If the terrain gets truly rugged, the Factor’s 43mm limit and road-stiff frame will hold you back before the Crux’s 47mm clearance does.
Specifications
Factor includes premium Black Inc components on its builds, including an integrated carbon barstem that reinforces its road-first identity. The LS uses a T47A bottom bracket, which is a solid middle ground between performance and maintenance, though early reviews noted some creaking in the press-fit version. Build options focus on 2x drivetrains like Ultegra Di2 or SRAM Force AXS, making it a capable quiver killer for riders who still spend 70% of their time on tarmac. Specialized leans into simplicity. Most Crux builds are 1x-only for mechanical groupsets, though you can run 2x if you go electronic. The S-Works build uses the new 13-speed SRAM Red XPLR, which offers a vast range without a front derailleur. However, the entry-level Crux Comp build is a bit of a letdown. Critics point out that its mechanical Rival 1x groupset and heavy alloy wheels feel underwhelming on a $4,000 bike. The Crux wins the maintenance battle with its standard BSA threaded bottom bracket and external seat clamp. It is a mechanic's dream that avoids the proprietary headaches common in modern gravel bikes. Factor’s integrated cockpit looks cleaner but makes front-end adjustments a chore. If you do your own wrenching, the Specialized is much easier to live with.
| LS | Crux | |
|---|---|---|
| FRAMESET | ||
| Frame | Factor LS carbon frame (Toray® & Nippon Graphite® PAN-based fiber) | Specialized E5 Premium Aluminum Disc frame with D'Aluisio Smartweld Technology, hydroformed aluminum tubing, tapered head tube, threaded BB, UDH dropout |
| Fork | Factor LS carbon fork | S-Works FACT Carbon, 12x100mm thru-axle, flat-mount disc |
| Rear shock | — | — |
| GROUPSET | ||
| Shift levers | Shimano Ultegra Di2 ST-R8170, 2x12-speed hydraulic | SRAM Apex |
| Front derailleur | Shimano Ultegra Di2 FD-R8150 | — |
| Rear derailleur | Shimano Ultegra Di2 RD-R8150, 12-speed | SRAM Apex XPLR, mechanical, 12-speed |
| Cassette | Shimano Ultegra CS-R8100, 12-speed, 11-34T | SRAM APEX XPLR, 12sp, 11-44T |
| Chain | Shimano CN-M8100, 12-speed | SRAM Apex D1 |
| Crankset | Shimano Ultegra FC-R8100, 52/36T | SRAM Apex DUB Wide, 40t |
| Bottom bracket | T47A | SRAM DUB BSA 68 Wide |
| Front brake | Shimano Ultegra hydraulic disc (ST-R8170 lever / BR-R8170 caliper) | SRAM Apex, Hydraulic Disc |
| Rear brake | Shimano Ultegra hydraulic disc (ST-R8170 lever / BR-R8170 caliper) | SRAM Apex, Hydraulic Disc |
| WHEELSET | ||
| Front wheel | Black Inc THIRTY FOUR, 700c | DT Swiss G540 rim, 24mm internal width, tubeless ready, 24h, Specialized full sealed bearing thru axle hub, centerlock disc, DT Swiss Champion 14G stainless steel spokes, DT Swiss brass nipples |
| Rear wheel | Black Inc THIRTY FOUR, 700c | DT Swiss G540 rim, 24mm internal width, tubeless ready, 24h, Specialized full sealed bearing thru axle hub, centerlock disc, DT Swiss Champion 14G stainless steel spokes, DT Swiss brass nipples |
| Front tire | Pathfinder 700x40, Tubeless Ready | |
| Rear tire | Pathfinder 700x40, Tubeless Ready | |
| COCKPIT | ||
| Stem | Black Inc Integrated Barstem (multiple stem lengths available) | Specialized, 3D-forged alloy, 4-bolt, 7-degree rise |
| Handlebars | Black Inc Integrated Barstem, 80mm reach, 120mm drop (multiple bar widths available) | Specialized Adventure Gear, 118.9mm drop x 70mm reach x 12º flare |
| Saddle | null | Body Geometry Power Sport, steel rails |
| Seatpost | 27.2mm round seatpost (not included) | Alloy, 2-bolt Clamp, 12mm offset, 27.2mm, anti-corrosion hardware |
| Grips/Tape | — | Supacaz Super Sticky Kush (bar tape) |
Geometry and fit comparison
Factor’s geometry is aggressive and unapologetic. A 566mm stack and 383mm reach on the size 54 means you are low and stretched. With a 72.3-degree head tube angle and a tiny 1005mm wheelbase, it handles faster than many endurance road bikes. The 76mm bottom bracket drop is deeper than the Crux's 72mm, which helps the LS feel stable on pavement but offers less clearance over chunky rocks off-road. The Crux is slightly longer and more relaxed, though its 388mm reach is actually longer than the Factor's. The 560mm stack is lower, putting you in a racy position. The 71.5-degree head angle and 67mm trail provide more self-centering than the Factor, making it easier to manage on high-speed descents. It has a longer 425mm chainstay, which provides a bit more stability compared to the LS's stubby 420mm rear end. Fit-wise, the Factor LS suits those who want their gravel bike to feel exactly like their road bike. The Crux offers more front-center length, which helps eliminate toe overlap—a common complaint on the Factor LS. If you have a long torso and high flexibility, the Crux’s long and low profile is a perfect fit. The LS, with its higher stack and shorter reach, might actually suit riders looking for a slightly more upright racing position despite its twitchy handling.
| FIT GEO | LS | Crux | |
|---|---|---|---|
| Stack | 530 | 530 | 0 |
| Reach | 372 | 375 | +3 |
| Top tube | — | 512 | — |
| Headtube length | — | 100 | — |
| Standover height | 748 | 749 | +1 |
| Seat tube length | 455 | 466 | +11 |
| HANDLING | LS | Crux | |
|---|---|---|---|
| Headtube angle | 71.5 | 70.5 | -1 |
| Seat tube angle | 74.5 | 75.5 | +1 |
| BB height | — | 284 | — |
| BB drop | 76 | 74 | -2 |
| Trail | 60 | 74 | +14 |
| Offset | 50 | 50 | 0 |
| Front center | — | 594 | — |
| Wheelbase | 990 | 1008 | +18 |
| Chainstay length | 420 | 425 | +5 |
Who each one is for
Factor LS
The LS suits riders who treat gravel as unpaved road cycling. If your rides consist of 40 miles of tarmac to reach 20 miles of well-groomed forest service roads, the Factor is ideal. It is a bike for the road racer who wants to maintain an aggressive fit year-round and doesn't plan on riding anything chunkier than Grade 2 gravel.
Specialized Crux
The Crux is for the weight weenie who wants a bike that feels explosive on every climb. If you live in an area with steep, punchy hills and you enjoy the under-biking challenge of riding technical singletrack on a drop-bar machine, this is your tool. It is perfect for the privateer racer who values simple maintenance and wants a single bike for cyclocross and fast road group rides.
