Cannondale Topstone Lefty 1
Top of the class? Enter the suspension-equipped Lefty 1
Cannondale brought lightweight bike suspension to the world of gravel in 2019 with its innovative, rear suspension ‘Kingpin’ system on its all-carbon Topstone. The Kingpin design uses a pivot at the top of the seatstays, which runs on a maintenance-free bearing, using the flex in the carbon stays and a seat tube engineered to act like a leaf spring, to provide 30mm of suspension travel at the saddle.
Cannondale’s innovative Lefty fork has appeared on a drop-bar bike before, on the ground-breaking Slate. Cannondale had a major redesign of the mountain bike Lefty in 2018 and this fork is pared down for gravel – it weighs 1340g compared with 1446g for the mountain bike version. This reshape allows for 47mm tyres in 650b and 45mm in 700c and the single-leg design means you don’t have to remove the front wheel to fix a puncture. The Lefty’s 30mm of suspension is matched at the rear by the frame.
What this Topstone gives you is so much more control. The fork has fast, reactive travel and if you factor in the huge 47c tyres, then the off-road capability is magnified. The tyres, like most mountain bike tyres, have differential treads – the front Venture tyre has block edges, which bite in the corners to provide grip, while the Byway rear has a much slicker tread pattern that’s great for helping to efficiently transfer your pedal power into forward motion.
It’s the same with cyclocross and it’s strange that it’s taken so long for road and gravel bikes to catch on to this way of thinking. Cannondale deserves credit for such a well thought-out spec.
The ‘mullet’ drivetrain – small in the front, large at the back – mixes SRAM’s Force road and Eagle off-road components, with the 12-speed
setup offering massive a gear range, thanks to its 10-52 cassette. This means you have an easiest gear that’ll keep you ascending when most will be walking, and at the other end a gear that is plenty for the fastest of off-road riders and for most on the road. The jumps between gears are larger than smooth-pedalling roadies are used to, but in low-traction situations you just don’t tend to shift around your gears quite so much.
I’d like to have seen the bar have more flare in the drops, as I like more wrist clearance when riding down in the drops off road. It would also be good to have a second set of wheels – 700c perhaps with a more all-round tyre, making it a genuine one-bike-for-all solution. Yet the ability to traverse bad surfaces is class-leading.
It retains the Topstone’s wonderful handling: quick but not twitchy, stable but not dull. It’s arguable that this Lefty-equipped bike opens up whole new terrain to explore. When you combine its mountain-goat gearing, controlled compliance from the suspension, generous tyres and the handling you get arguably the most capable gravel bike around.