Gravel, All-Road, Adventure Bikes…I’m interested in design not what you call it

Gravel, All-Road, Bikepacker, Adventure Bike….marketing terms for a somewhat nebulous and ill-defined target demographic into which bicycle brands have desperately been hurling new product development. Golly, I do like bike design but I hate the debate over what is the most appropriate name for the genre. It’s just like that one song, “you say tomato, I say f*** you”.

As if one term can reign in all the conflicting ideas and give a hierarchy to the products, yet that is the goal of the nefarious science known as marketing. I don’t really have the head for that kind of mysticism and etherealism; I’m more interested in the corporeal, the carbon, and the titanium. What is the product, where did come from, where is it aimed?

Three bikes have caught my attention recently. The Salsa Cutthroat, the Open Cycle UP, and the Cannondale Slate.

With a stable of successful house brands including Surly and Salsa (and sort of successful brands like Civia), QBP have been quick to capitalize on recent trends such as fatbikes and now that….you know….gravel/adventure thingie. This month Salsa introduced the Cutthroat….named after some sort of fish (gotta name a bike something, I guess). They call it a mountainbike for dropbars, a race bike for the Tour of the Divide, equipped with 2.4” 29er tyres. Well, there have been dropbar mountainbikes in the past. Famously, the legend that is John Tomac raced a dropbar mtb on the NORBA circuit fresh off racing road with the pro European peloton about 25 years ago, but drawing a direct lineage between Tomac’s experiment and the Cutthroat is strained at best. That’s probably because the term “mountainbike” is hard pressed to encompass both a 2-3 hour NORBA-style mtb race and an adventure-style race that may a week or longer, basically unsupported.

The Cutthroat can be thought of a premium, carbon development of their metal-tubed Fargo series of framesets and bikes. Along with a series of offroad-focused dropbars (Woodchipper and the more subtle Cowbell series), these bikes have geometry that puts the drop into the hands of the rider by having a reach and stack dimensions dramatically different from today norm for mountainbikes. Though flatbars (and riser bars are really just a variation of the flat bar) give better control on really technical terrain, dropbars offer multiple hand holds that allow a rider to subtly change body position, something that becomes very important as the hours in the saddle pile on.

Twenty-five years ago, before suspension forks were ready for mainstream market acceptance, mountainbikes (with flatbars, of course) already had somewhat long top tubes relative to road or touring bikes, but they often had 135 or even 150mm stems to get the long reach needed for technical climbs. In the years that followed, fork travel grew and bike makers such as Gary Fisher kicked out the front centers and shortened the chain stay dimension on their frame designs. Today, mtb stems are most often shorter than stems on dropbar equipped road, touring, or cyclocross bikes. This makes the contemporary mainstream mountainbike particularly unsuited to being retrofitted with a dropbar, because the extra reach of a dropbar can’t be compensated for with a shorter stem. Also, the necessity of putting the drops of the bar high enough for technical riding requires a higher stack height from the frame, since threadless stems cannot easily replicate the height of yesteryear’s quill stems. Salsa’s Fargo and now Cutthroat designs remedy this by having shorter reach and taller stack dimensions. The stack is partially helped by having a suspension corrected 29er fork that is 483mm axle-to-crown

Oddly, if you just look at the numbers on Salsa’s geometry chart, you could reasonably conclude that Cutthroat was a touring bike…with 29er tyres….instead of a mountainbike with dropbar….again with the tomato song.

Whatever you call it, the strong point of the Cutthroat is its tuned carbon frame that also offers a multitude of attachment points for gear and hydration. The less compact front triangle leaves plenty of room for frame bags. In fact, Salsa/QBP plan to offer a line of bags to compliment the new bike. Though you could replace the “Firestarter” carbon with a XC 29er fork, you’d be stepping away from the Cutthroat’s goal of lightweight and efficiency.

Where is the design going? Who is going to buy it? The Cutthroat is about bikepacking, riding over long trails with very little dawdling about on the way. The bike is meant to store a lot of gear in bags that keep the loads centralized on the frame, so as not to affect handling on singletrack. In this respect, the Cutthroat stands apart from traditional touring bikes, which rely on traditional panniers and racks to carry supplies. But while gigantic saddle bags and fitted frame bags keep the Cutthroat agile offroad, I would rather have traditional panniers for regular around-town needs, since the good panniers are quicker to strap on or off as well as being more convenient for loading things like groceries. The Cutthroat isn’t going to rival a good cross-country machine on a typical race course either. In the end, I’m just not sure how this bike is going to do on the market. I mean, it’s interesting….but really does have a narrow range to shine. Too bulky and overbuilt for road touring, not agile enough for hairy end of technical riding, and too expensive to have as half-hearted fling. Maybe bikepacking will grow as a demographic, but it’s hard to see it garnering as many fans as fat bikes. Fat bikes are chugging along on the idea that fat tyres are more fun for all situations not just Iditabike (frankly I have my doubts that they can sustain that kind of growth anyways…and I’m not the only one in the industry to say that), but Salsa is specifically linking the Cutthroat to the Tour of the Divide. On the other hand, images of the Paris-Dakar Auto Rally have probably sold a lot of Range Rovers over the years, and probably a lot of those consumers don’t even know where Dakar is.


Last week Cannondale popped in out of nowhere with a little video production featuring the Slate, a gravel bike using a version of their unique Lefty suspension fork. But while the eye is immediately drawn to the awkward asymmetry of the 30mm travel pogo-stick-with-disc-brake, Cannondale threw a curveball by equipping the Slate with 650B wheels/tyres. This is pretty hot to me, since I’ve sorta been hip to the 650B renaissance for a while now. Many readers already know that 650B (aka ISO 584mm) is a rim/tyre standard that shares the same origins as the far better known 700C (ISO 622). Before it was chosen at the Goldilocks/mid-sized wheel for mountainbikes about 6-8 years ago, 650B had only survived on city bikes and French randonneur bikes. This year there is hardly an mtb maker that doesn’t have at least one model with 650B wheels (or 27.5” as the marketing people want you to think). Now with supporters like Pacenti, Compass Bicycle, and Grand Bois, there has been a recent resurgence in road tyres for the 650B standard, particularly large volume casings 32 to 42mm wide.

Why a different wheel standard? Well, just about everyone on both sides of the market agrees that wider tyres are better for these gravel bikes, but how wide can you make the tyre before you have to compromise the geometry of the frame to fit it? Once you get bigger than 32mm you start to run into problems in the area behind the bottom bracket. With a typical road bike having chain stays 410-420mm, the tyre is competing for the same lateral space as the chainrings and the chain stay tubes themselves. As the outer diameter of the tyre approaches 38mm, clearance between the tyre and the seat tube becomes an issue. Eventually the frame designer must either lengthen the chain stays or abandon road cranks with their narrow chainline and chainrings bigger than typical mtb options. The Cutthroat does exactly that, having 445mm chain stays and using cranks typically seen on 29er mtb. That’s fine for carrying stuff for a multiday adventure into the wilderness, but that’s a far cry from the spirited handling of a road bike. By using 650B x 42mm tyres, the Cannondale Slate achieves the desired air volume without encroaching on frame clearances. Even more, since the disc brakes don’t require a specific rim diameter you can actually alternate wheels/tyres between 700Cx28 and 650Bx42 without changing the bottom bracket height, since the two combinations have the same outer diameter. Sure, Jan Heine would say that the 650Bx42 tyre is faster in ALL CONDITIONS, but I like the option of running regular road wheels. Going back to that Lefty-equipped Cannondale Slate, the 650B wheel also keeps the stack height at the front low and sporty for the road.

I find the idea of suspension for all-road intriguing. I have ridden extensively on a Rock Shox Paris-Roubaix SL fork, the very same design that won Paris-Roubaix three years in a row during the early 1990s, but the only thing I can say without reservation is that 25 year old suspension technology sucks compared to modern one-piece lower castings, 32mm plus stanchions, and dampers that actually work. If Cannondale wants to make a road/all-road/gravel suspension fork with up-to-date features and construction, I wanna test it out. If a 30-50mm travel suspension forks proved to be a hit, who knows how the designs could change and genre evolve?

Of course, Cannondale’s offering has to be taken with a grain of salt. Cannondale has a long history of flashing product to the media long before its development is complete, and a less generous opinion is that they serve up a lot of vaporware (does anyone else remember the Cannondale/Magic Motorcycle showbike?). The Slate bikes in the video are clearly welded aluminum, which while still a viable production method and one that few companies do better than Cannondale, the ease at which it can be used to quickly create one-off designs doesn’t really impress me that Cannondale is committed to this idea.

Lastly, there’s Open Cycle, the new brand started by Gerard Vroomen, formerly of Cervelo. Initially with a focus on hardtail 29er mountainbikes, Open chose a gravel/all-road frameset as their second offering, but what a rather ambitious and unusual design it is. Besides all carbon construction and front/rear thru-axles, the Unbeaten Path (or “UP”) plays the dual wheel size trick with 650B/700C, but instead of 42m tyres the UP can take a honking 55mm x 650B better known to mountainbikers as a 27.5” x 2.25” knobby (incidentally the UP can also take a 40mm x 700C tyre). Remember what I said about big tyres and short chain stays being busy behind the bottom bracket? Well, Open beats the problem by dropping the driveside chainstay down to snake below the point where the tyre tread gets closest to the chainrings, thereby allowing the chain stay to keep a meaty enough section to maintain drivetrain stiffness. And the UP can still fit a 50/34 compact road crank. Surely 3T had an easier time designing the Luteus II fork to fit an equally wide tyre up front, but it is still worth noting that the new fork surely has more tyre clearance than any other full-carbon fork at a 395mm axle-to-crown, which is something of an industry standard height for cyclocross fork. It is yet unclear whether the fork will be available through 3T distribution channels or whether it will remain an OEM exclusive to Open Cycle. Beyond fitting inches of rubber into rear triangles like clowns into circus cars, the UP has what looks to be a rather low stack height, putting emphasis on speed. This bike is more gazelle than pack mule. In fact, the prototypes don’t even have eyelets for racks or fenders, which struck me as daring but stupid from a marketing perspective, as it would thoughtlessly limit the bike’s capabilities. I was relieved to find out that these were stage 1 of a 3 stage development progression, and that eyelets were planned for later after the rest of the design details had been tweaked.

I’m really interested in Vroomen’s design philosophies. I saw a steady evolution in geometry during the time he was at Cervelo, in particular how the first Cervelo road bikes all had 73deg head angles and 43mm rake forks regardless of frame size. As some of you readers would know this means that the smallest frames end up with wicked toe overlap, something I personally dislike. More recently, the smaller Cervelo road bikes have slacker head angles balanced out with longer rake forks, so that the trail dimension is kept relatively constant throughout the size range. However, I have my doubts that the market is sophisticated enough to appreciate the possibilities that 650B/700C dual capability gives. The other thing is that I don’t understand Vroomen’s marketing/distribution strategy. It seems like he’s going direct sales and using pre-sales of the UP to help with development costs. More power to him if it works out, but Open Cycle will never have the sales numbers to really shape the market segment. Pity that, because I think I like what he’s got cooking.

Ed note: While Mark wasn’t as interested in it as me, another bike in this new category is the Trek 920

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