These frames use a rigid rear triangle that’s connected to the mainframe by a pair of short links. It’s another form of four-bar linkage, but with the chainstay pivot much closer to the main pivot than on a Horst link design. Again, the axle’s direction is dictated by a moving instant centre. Some twin-link set-ups, such as Santa Cruz’s ‘VPP’ (Virtual Pivot Point), Intense’s ‘JS Tuned’ and DMR’s ‘Orbit Link’ systems, use links that counter-rotate (turn in opposite directions). Others, including Giant’s Maestro layout, Mondraker’s ‘Zero’ system and Dave Weagle-designed ‘DW-Link’ bikes (Pivot, Ibis), have links that co-rotate (turn in the same direction). With counter-rotating links, the curvature of the axle path can be made to vary through the travel. This can provide anti-squat values that peak in the middle of the stroke, where pedalling efficiency is most important, while minimising pedal kickback elsewhere in the travel range.