Ah, it’s been a while, and if I’m honest with myself, I knew this was coming. It’s every bike journalist’s biggest nightmare: trying to explain how Trek’s IsoSpeed damping works. So here goes:
Get a cheap biro. Hold it horizontally, one end in your hand. Now bend the other end and see it arch its back in the middle. Now imagine you are sitting on the biro and it has wheels. This is IsoSpeed, sort of, in that the seatpost is fixed to one end of the biro, and the biro is really a carbon strut housed inside the top tube, bolted at one end of the top tube and allowed to pivot (and so bend) at its
