Factor Sarana gravel bike review – an extreme gravel option designed to take you places your regular bike couldn't dream of

The gravel sector has exploded with bike options and, while choice can be a good thing, it's created a tricky landscape to navigate – particularly for the new buyer just entering the discipline. One-model gravel lineups are no longer commonplace, with manufacturers now creating distinct lineups with individual bikes aimed at various gravel offshoots. This means you'll see road bike-style options with bigger tyre clearances, inbetweeners that balance pseudo-suspension with weight and speed, and models that closely resemble mountain bikes of yesteryear.

It's confusing to say the least, but the gravel cycling discipline and terrain are so diverse depending on where you live, ride and race; sometimes you need a specific tool for the job at hand – a scissor can prune a tree, but a pair of secateurs will do a better job in less time.

This leads me to Factor’s current gravel bike lineup. It currently spans three distinct models – the Aluto, Ostro Gravel and Sarana pictured here, each of which has a specific use case and function. While the former two are designed with all-round ability and pure speed in mind, the Sarana pushes the gravel concept to the extreme, catering to ultra events and bikepacking, where riders spend days in the saddle, often self-supported in remote areas that require a capable and reliable machine.

To complicate things even further, we also recently spotted a new Factor gravel prototype at Unbound, which appears to adopt a similar wide-set fork as the Factor One aero road bike, and looks designed as an out-and-out racer. This could take Factor's gravel offering up to four models, with two extremes bookending a brace of all-rounders.

The birth of the Sarana was no accident but rather the result of the Factor design and engineering team’s effort to create a brand-new machine, unsullied by current gravel bike trends and capable of supporting Canadian endurance athlete Rob Britton. The project started nearly three years ago and was heavily inspired by real-world feedback from Britton – focusing on speed, comfort, and control – important attributes for when races push past the 20-hour barrier.

While the average customer will never push the Sarana to these extremes, it’s still pretty adept on shorter excursions, too, and does an amazing job of smoothing out rutted terrain, washboard gravel, and mountain trails.

Design details

The Sarana is an intriguing-looking bike – quintessentially Factor, with a blueprint that sticks to the classical form-over-function design philosophy. The aesthetics are divisive though, and you'll either love it or hate it. There are two colour palettes available, the cyan blue pictured here and prismatic gold – both are muted but draw on the natural tones of the outdoors and the various hues experienced when riding from dusk till dawn. The graphic design is bold, with the Factor and Sarana wordmarks positioned prominently on the downtube and seat tube.

The Sarana is manufactured from Toray and Nippon Graphite pan-based fibres, tuned to balance stiffness with comfort and vibration-damping – similar ingredients to the Factor Aluto. The frame architecture comprises three distinct yet seamlessly integrated areas: the front, middle and rear, which represent a departure from how the company developed the Aluto and Ostro Gravel platforms. Like many modern gravel platforms, it’s compatible only with 1x groupsets and comes with a handy 30.9mm external seatpost clamp to accommodate a range of dropper posts.

It draws inspiration from the Monzo road bike, featuring a truncated aero profile and subtle hourglass sculpting on the headtube. It also comes stock with a collection of purpose-built 'aero' bike bags that fit within the triangle and above the top tube to help extend the leading edge of the tube shapes and the sailing effect at certain yaw angles.

The backbone of the Sarana is the down tube area, which has been purposely oversized to add torsional stiffness and hollowed out for optimal internal storage capacity. Factors claims that the downtube sculpting promotes cleaner airflow over the frame and that the centre of gravity is low and balanced when laden with tools.

The rear end is all about terrain management, and tyre clearance is at the forefront. While not the market leader in this instance, the Sarana can accommodate tyres as wide as 57mm (2.2-inch). Our test bike came with Black Inc 46 carbon wheels wrapped in 2.0-inch Continental RaceKing mountain bike tyres.

To accommodate rubber this wide, the Sarana features dropped seat stays and an offset seat tube, which double up as a natural leaf-spring system that flexes while maintaining lateral progress. Clever directional layup techniques have been implemented at the bottom bracket junction to manage fatigue and traction, resulting in an 18 per cent reduction in vibration.

Specifications

Our Sarana test bike came outfitted with SRAM Force XPLR AXS, featuring a 44T up front (the frame does have provision for up to a 52T chainring) and a 10-46T rear cassette. There's nothing wrong with Force – I rate it on par with Red AXS when it comes to performance and aesthetics; it's just heavier.

To ensure better stopping performance when fully rigged, the native 160mm front/rear brake rotor configuration can be flipped if you prefer the added security of larger 180mm disc rotors. The platform was optimised for SRAM but is also able to run various Shimano Di2 groupsets (wired versions, too) - there’s a Di2 exit port above the UDH triangle.

Five frame sizes are available, spanning 49, 52, 54, 56 and 58cm – one less than the Ostro Gravel and Aluto models. The Sarana’s geometry numbers are racier than you’d expect from an endurance-themed machine with a 71.5-degree head angle and 65mm trail figure (identical across all sizes) and a 74- 75.3-degree seat tube angle. The reach (398mm) and stack (573mm) on a size medium are very close to the Ostro Gravel and border on aggressive.

The 425mm chainstays and offset seatpost have made room for up to 57mm tyres, while the 80mm bottom bracket drop sits slightly lower than its rivals and stablemates. While not outrageous, tyre clearance falls between the recently released Specialized Crux (55mm) and Open Wi.De 2.0 (66mm).

Factor also suspension-corrected the geometry to ensure parity when specced with a 30mm RockShox Rudy XPLR fork with sag, evidenced by the 427mm axle-to-crown measurement.

Performance

The Factor Sarana is not your typical racing gravel bike, but it can take you places and traverse terrain many of its rivals can’t. While there are many faster and lighter options on the market, "faster" is contextual, and when the terrain gets rocky or washboard gravel comes into the equation, there aren't many bikes able to match the Sarana for speed and comfort. And it’s in these technical and rough settings that the Sarana should be experienced and ridden in anger, not on champagne gravel and definitely not on tarmac.

A gravel bike as capable as the Sarana also questions the need for a mountain bike – especially where I live in the Surrey Hills – thanks to the front suspension and fairly relaxed head angle. It copes just fine with everything that has come its way – and I’m talking fire roads, twisty singletrack and step-downs. It feels controlled and completely adept when things get gnarly. Don’t get me wrong, a cross-country mountain bike will be faster down rough, negative gradients, but then again, a bike of this nature won't keep up with the Sarana on 80 per cent of the gravel routes in the South East of England.

One bugbear is the narrow clearance around the fork crown and tyre. The back of the crown tends to collect dry leaves and debris, and this rubs against the tyre. I’d like to see how the Sarana deals with mud come wintertime, and whether the crown/tyre clogs up or not – this is a known issue with the RockShox Rudy fork. You can substitute it for a rigid fork, which does nothing to adversely affect the head angle and trail number – the bike was designed to work seamlessly with both options.

At 9.75kg with RockShox Rudy XPLR fitted, the bike isn't the best at climbing, but it holds momentum well and conforms to the terrain, nullifying most vibration-induced speed loss associated with off-road riding. I haven't felt held back by the 2.0-inch Continental RaceKing mountain bike rubber. If anything, the grip offsets any weight or rolling resistance penalties. After all, there’s more time to be lost on the downhills than on the climbs, and this width affords the rider confidence to push harder and not overthink the situation.

Our test bike came fitted with a 44T single chainring, which perhaps holds it back from unlocking an even greater top end, but it’s not often my gravel routes touch speeds of over 50km/h. During my initial testing, I mulled over the idea of trying a 52T ring, but given the final drive ratio of 4.40, the 44T was all I needed, and I never felt my cadence getting too high. The 10-46T cassette provides ample gearing for most vertical excursions. It only really becomes hard work on double-digit gradients with loose surfaces.

It’s no slouch on the tarmac, but it wasn't designed for it and riding it in this setting would be doing the bike a disservice – you’ll get the most enjoyment for your mile off the beaten track.

Value

The gravel bike sector is a tricky space to navigate at present, with bike technology evolving apace – and offshoots focusing on aero gravel, all-round riding and adventure, take your pick. While there’s a lot going on, the upshot is a variety of bike choices, which wasn’t the case just five years ago. At that juncture, Factor had more variety than its rivals with the Vista and LS platforms, and the company has continued this stance with its three (maybe four if the prototype bike we saw at Unbound goes into production) bike approach to gravel.

For many, the Factor Sarana will represent a solid choice – even at £8,299/ $8,499/ €10,199 (7,699/ $7,899 /€9,499, if you spec it sans suspension fork). Owing to its breadth of attributes, I foresee a convergence of curious road riders and mountain bikers. It’s neither road-bike racy nor mountain-bike burly; instead, it blends both disciplines, and the result is one of the most enjoyable drop-bar dirt bikes I've ridden this year.

I didn't want to like the Sarana, but I find myself appreciative of the concept, and the variety of riding it affords me; from road and hardpack gravel to semi-technical mountain bike trails – particularly if it's specced with the suspension fork. I never once felt uncomfortable; if anything, it made sense on the trails I ride from the moment I pressed the pedals for the first time. For the kind of off-road riding found across most of the UK, the Sarana is totally up for the task. It’s accommodating when it comes to storage and luggage capacity, compliant on the rough stuff, nimble enough to satisfy speed merchants, and capable when things get truly challenging.

It’s not as fast as a bona fide gravel racing machine, but that’s not what the Sarana claims to be. If you’re after one bike capable of dismissing all conditions and challenges and going to remote areas far off the beaten track, the Factor Sarana might be the answer.

Tech spec

• Price: £8,299/ $8,499 /€10,199 
• Brand: Factor
• Frame: Factor Sarana (Toray, Nippon Graphite, Pan-Based Fibre)
• Fork: 30mm RockShox Rudy XPLR
  Weight: 7.75kg (actual, 54cm)
• Sizes: 49, 52, 54, 56, 58cm
• Levers: SRAM Force AXS
• Brakes: SRAM Force AXS
• Rear derailleur: SRAM Force XPLR AXS
• Front derailleur: N/A
• Crankset: SRAM Force XPLR Dub Wide, 44T
• Bottom bracket: SRAM Dub Wide press fit
• Cassette: SRAM Force XPLR 10-46T
• Chain: SRAM Force
• Wheels: Black Inc 46
• Tyres: 2.0-inch Continental RaceKing
• Bar/stem: Black Inc Integrated 
• Seatpost: FSA SL-K SB0 (compatible with dropepr post)
• Saddle: Selle Italia SLR