"Gravel bikes" are becoming increasingly popular, as they combine some of the toughness of mountain bikes with the speed of road bikes. Given that they travel on dirt trails and unpaved roads, though, some suspension might be good – and that's what Cannondale's new Topstone Carbon offers, in a novel fashion.

The carbon fiber-framed bike features what is known as the Kingpin suspension system, which incorporates a single thru-axle pivot in the seat tube, at the point where the seat stays connect to it. This setup facilitates the movement of flex zones in the rear stays, seat tube, and rear section of the top tube, providing up to 30 mm of suspension travel.

As a result, bumps and road vibration are reduced (in the back, at least), while comfort, traction and control are increased. The system is additionally claimed to require no set-up and virtually no maintenance, plus it does away with the added weight and complexity of shocks, linkages and multiple pivots.

The Topstone Carbon was announced this Thursday, and is available in five models priced from US$2,700 to $6,500.

For other examples of rear suspension for non-mountain bikes, check out what Pinarello and Calfee have previously come up with.

Source: Cannondale via BikeRadar

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