Tested: Cannondale Slate CX1

The not-so-minor details


Cannondale Slate CX1


Monza Bicycle Imports






Fun on the dirt, but fast on the road.
Wheel/tyre format works well!


Noisy bottom bracket.
Held back by tyres.

Hello, you freaky weird machine.

What is it and who is it for?

Upon reflection, we love this bike.

The Slate is a… ummm…. gravel bike? Road-ish bike?… An almost CX bike? A mountain bike with drop bars? If you really want to break it down, the Slate takes its bars and slick tyres from the road world. It has the groupset and brakes you’d expect to find on a CX bike, but its wheel size means you can’t race it. The tyres are a broad 42mm like you’d usually find on a gravel grinder, but the wheels are a 650B diameter, a size that you’d normally associate with a mountain bike. Oh, and it has a Lefty with 30mm travel too.

Great graphics and classic Cannondale frame finish quality.

So does this make the Slate a jack of all trades, or is it paralysed by indecision on all fronts? Or should we just shut the hell up, forget trying to pigeon hole it, and ride the damn thing?

If you really want us to come up with a label, we’d say the Slate is… a… shit load of fun. We rode this bike on everything from CX bunch rides, to 120km gravel and tarmac adventures, to punchy road training rides and a bit of singletrack too.

Frame and build

Internal cables and smooth finished welds.

The Slate frame obviously stems from Cannondale’s venerable CAAD series road bikes, especially now that they also come in a disc braked version. The aluminium frame is lively, you can feel how thin and lightweight the tubes are just by giving them a gentle squeeze. (Not too hard!) The sleek anodised black finish is made even more slippery with those classic smooth-finished welds that have long been a hallmark of Cannondale alloy frames.

The chunky axle just looks out of place.

Starting out back, the Slate’s 142x12mm rear axle setup is a bit ho-hum. Full marks for embracing the 142mm standard on this kind of bike, but this particular axle feels and looks clunky in comparison to the rest of the build.

While the big volume of the tyres will do most of the comfort enhancing, the chain stays and seat stays get Cannondale SAVE treatment and are flattened out to provide you a bit of give, and the 27.2mm post has a bit of flex about it too. Bung in a carbon post and you’ll have even more compliance. We’re happy to see there’s decent amounts of tyre clearance, so adding something with some side knobs is do-able.

The Hologram SI cranks are very light, but our BB30 bottom bracket was a bit noisy when hammering out of the saddle.

Having a single ring drivetrain and losing all the faff normally associated with a front derailleur instantly makes a bike look cleaner, and Cannondale do a fine job of internally routing the gear and brake lines too. We did hear a tiny bit of cable rattle from the brake line inside the frame, but jamming a bit of foam in there will alleviate it.

Like a lot of Cannondales, the Slate gets a BB30. Unfortunately, ours developed an annoying ‘click’ after a few rides that would rear its irritating head on every left-hand pedal stroke when climbing out of the saddle. We didn’t have the tools handy to pull the whole assembly apart, and not many home mechanics would either.

With the spacers atop the stem, the riding position wasn’t too upright for the road, but still felt great for our shorter test rider on the gravel and dirt too.

Even with the Lefty Oliver strut, the Slate’s riding position can be made relatively aggressive up front. With all the spacers removed, we were able to get the low enough that we didn’t feel at all awkward and upright on the road, with plenty of weight over the front wheel when cornering. If you’re going to be spending more time on the dirt, there’s enough steerer tube there to give you a more of an upright mountain bike-ish position if that’s what you prefer.

The Oliver

If there’s one element of this bike that really sets it apart from other gravel grinder style bikes, it’s the Lefty Oliver. Deriving its name from the fact it allows you to ride ‘All Over’, it has all the usual air spring and rebound adjustability and lockout stuff you’d find on any other Lefty, just chopped down to 30mm of travel.

Not your average looking front end!

If you’re going to spend the vast majority of your time on the tarmac, then you could argue the Oliver is overkill, but as soon as the roads get rough or you hit the dirt, then the Oliver gives this bike a real edge. 30mm isn’t a lot of travel, but when you pair it up with the extra cushion of the big rubber you’ve suddenly got the ability to hammer, steer and brake where you’d simply be hanging on on a rigid gravel bike.

When you’re on the bitumen, you can hit the lockout too, so really the only penalty is the weight. Worth noting, is that if you’re on a smaller frame, or you’ve just got long legs, you might find yourself occasionally brushing your knee against the top of the Lefty.


All the bits

CX1: If you’re approaching this bike from a road background, you might be irked by the idea of a 1×11 drivetrain, but it’s really one of this bike’s standout elements. A 44 tooth Spidering, with a SRAM X1 10-42 cassette gives you a huge spread. We never found ourselves wishing for more gears, at either end of the range! The jump when shifting between the two highest gears – going from a 13-tooth to a 10-tooth – is a large one, though you only ever really need the 10-tooth once you’re above 50km/h.

A 44-tooth narrow/wide Spidering.

Cannondale have specced a petite chain guide too, and while we’d be happy enough running the bike without it (we don’t use a chain guide on other CX1 equipped bikes) it’s good to have the peace of mind especially if you’re off road.

Brakes: SRAM’s Force Hydro brakes with a 160/140mm rotor combo always had enough grunt. The rear caliper uses the new flat-mount standard, which looks super clean, but we found a bit fiddly to stop the brake dragging. As we’ve noted above, having so much rubber, especially when you’re on the road, lets you make the most of the brakes’ power.

Big hoods give you plenty to hang onto!

Great contact points: We really like the Fabic Scoop saddle, it’s comfy whether you’re on the hoods or the drops, and the Cannondale branded bar tape is quite thick for a bit of cushion as well. The tough metal expanding bar plugs are a nice touch too.

Fabric saddles are fast becoming a favourite at Flow.

Rolling gear: Cannondale’s own purple sealed-bearing hubs awaken the 90s revivalist in us, and while the rims are pretty bland looking they are tubeless ready. The tyres are made by Panaracer for Cannondale – they’re a proper 42mm wide, and tubeless compatible. They’re definitely designed for more on-road use than the dirt; there are no cornering knobs, and the sidewalls didn’t take long to show some signs of wear after a few rides on rockier terrain, which led to bit of air seepage. If you’re looking to spend serious time on the dirt and gravel, some tyres that are better suited are going to be your first upgrade, but if you’re on road solely they’re excellent.



So, where does the Slate call home? We first began reviewing this bike right around the time we interviewed Jeremiah Boobar from Cannondale. His advice was ‘ride it everywhere you’d normally take your road bike.’ While you’re never going to win a criterium on this thing, it’s on-road performance is actually pretty decent, and for the average roadie or commuter racer, it’s really a good solution.


The diameter of the 650B wheels with 42mm rubber is only marginally smaller than a 700c rim with a 25c tyre, so it trundles along well. But, of course, you’ve got a lot more rubber on the road which means better braking and more grip overall. The kind of insignificant crap that can so easily spell disaster on roadie (like a cats eye, a grate, or a stick on the road) don’t present the same risks when you’ve got all this grip.


If you’re thinking the big rubber means it’ll be a pig, you’ll be disappointed – it’s pretty quick! We surprised ourselves by setting some of our fastest Strava times on road segments that we’ve ridden dozens of times on ‘proper’ road bikes, an we rarely even bothered to hit the Lefty lock out. You’d probably get some evil looks from the well-groomed roadie folk if you turned up for a bunch ride on the Slate, but we doubt you’d get dropped in a hurry. And you’d definitely be able to huck more speed bumps.


When the road turns to gravel or dirt, the Slate is only held back by its tyres. You can drop the pressures down in the 35psi range to get some more grip, but this bike is begging for something with cornering bite and some more climbing traction to make the most of its abilities and low gearing.


At this stage, there aren’t a huge number of tyres in 650B diameter and a 40-45c width, but that’s changing. Schwalbe’s G-One, the Rock ‘n’ Road by Panaracer and the new Maxis Rambler (coming in a 650b soon) are all options, amongst others. Still, at this stage it’s unlikely you’ll be able to walk into a store and have many tyre options at your fingertips for some time yet.

In all other respects, the Slate is pretty much ideal for getting out onto country dirt roads where you’re not sure what you’re going to encounter. The riding position is really secure – even if you’re up on the hoods, the big reservior of the Force brake levers gives you plenty to hold onto, so you can barrel into things knowing you won’t blow your hands off the bars.



It’s kind of hard to wrap this one up, because there’s just not a lot out there to compare the Slate to! As a road bike, the Slate makes a huge amount of sense to anyone who’s coming from a mountain bike background – the idea of big rubber at lower pressure, disc brakes and bolt-up axles just makes sense. It’s not even that heavy, maybe a kilo more than most roadies. If you’re a gravel rider, get some grippier tyres on this bike and you’ll be in love. If you think this bike is an answer to a question nobody asked, then clearly we’ve all been asking the wrong questions.


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