Review: Cannondale Slate Ultegra

What the heck is this thing?
It seems completely out of left field. It’s a mountain bike with drop bars, right? Not even close. So it’s an adventuremobile gravel grinder? Wrong again. Cannondale labels the new Slate as a “new road” bike, and I’d say it leans heavily toward just that: roads. Dirt roads sure, but if you were expecting an all-terrain monstercross machine, this isn’t it.
At its introduction the engineers explained that the very reason the bike was built with 650b wheels was that the smaller wheels with larger tires kept the overall circumference of a 700c race tire. Despite the added height of the suspension fork they were able to maintain the stack height they wanted and the 405 mm chainstays. The bike’s fit falls somewhere between the Supersix EVO race bike and the Synapse endurance bike. The Slate does have a longer front center and slacker head tube, though.

So, it’s a road bike with suspension? It’s not a new idea. RockShox was building a road bike fork in the early 1990s and it had success in pro races across the brutal Belgian cobblestones. Cannondale was also making versions of its road and cyclocross bikes with a Headshok a decade ago.

This time around the Slate uses a completely new version of Cannondale’s unique Lefty suspension fork that has a dedicated following in the mountain bike world. (Nerd alert: It’s technically not a fork at all, but a strut.) Known as Oliver, it has 30 mm of travel controlled through an air spring and has adjustable rebound damping via a knob on the top and a lockout button labeled “Push to climb.” With a completely new damper designed just for the Slate, it has a high compression threshold and limited sag so it doesn’t bob into the mid-stroke while you’re riding.
What you’re really buying here is a very high-end fork with a frame attached to it. In this case it uses Cannondale’s classic aluminum construction with more compliance built in than any previous model. The seatstays and chainstays use radically shaped tubing to allow the frame to match the comfort of the fork. Err, strut. Cannondale could have used the 25.4 mm seatpost of its Synapse line for even more compliance, but instead it opted for 27.2 mm so it can accommodate a dropper seatpost. Drop bars and dropper posts will be the story of 2016. You read it here first.
The Slate we tested was the middle of three build kit offerings, with an 11-speed Shimano Ultegra drivetrain running through Cannondale’s own Hollowgram Si crankset with 52/36 chainrings and an 11-28 cassette. The shifting works well, but the feel of the cable release lever is still a bit vague for my liking.
The frame has eyelets at the rear dropouts to attach fenders or a minimal rack, but without eyelets at the top you’re going to have to get creative. A front fender is a DIY-only affair at this point. I learned the hard way that because there is no fork crown, if you ride on wet roads a plume of water shoots directly up in the air off the front wheel, subsequently spraying you in the face.

All in all, the Slate rides like, well, a road bike. The posture is classic skinny-tire aggressive, but unless you look down you might not even notice the larger rubber. The 42 mm tires themselves, made by Panaracer for Cannondale, are amazingly light and supple with a faint file tread. Both the wheels and the tires are tubeless compatible, but the Slate doesn’t ship with them set up as such.
I’ll admit, when I first caught wind of this bike I expected something more akin to a “gravel” bike or monstercross. Now that I’ve met the design team and ridden the bike, I can say that isn’t what we have here. There isn’t much room in the frame for more rubber or a knobby tread, so forget about putting mountain bike tires on it. I think it falls much closer to the “road” end of the spectrum than it might seem at first glance. As such, it has absolutely no problems holding its own in a paceline or in a group ride. It has all the responsiveness of a traditional road bike, albeit an outrageously comfortable one.

Here in Oregon, we have endless dirt roads through the misty coastal mountains, and this is where I had the most fun on the Slate. The fat tires neutralize high speed vibrations from the ground while the Lefty Oliver eats potholes for breakfast. While the lockout button is within easy reach, I felt fine leaving the compression open all the time, and the Oliver was only absorbing bumps and not watts. I took the Slate through all kinds of pavement, gravel, dirt, mud, roots and rocks and it really is a versatile machine.
Yes, a more aggressive tire would have been appreciated when I started venturing into some singletrack, but that’s really at the very edge of this bike’s intended use. What is the intended use? The Slate is for anyone who wants a really, really comfortable road bike. With the current state of American roads and infrastructure, perhaps that isn’t a bad idea. Here at Bicycle Times, we’re big fans of pushing boundaries in terms of where you can take your bike. Maybe it’s a new road, after all.

• Price: $3,520
• Weight: 20.9 pounds
• Sizes: XS, S, M, L, XL (tested)
• More info: Cannondale Slate