Moto Morini






The standard Marzocchi fork is quite generously sized for the weight of bike and has a decent stiff set of yokes. However the damping is really quite crude. It simply works by forcing the oil through fixed orifices. This means that the forks are underdamped at low velocities (undulations in the road, braking, etc.) but overdamped at high velocities (a step in the road surface for example).

Modern 'cartridge' forks use sophisticated 'shim stacks' which can give almost any response curve desired. It's possible to get the Marzocchi forks converted to modern internals (Maxton for example), but it's expensive. A cheaper option is to use 'cartridge emulators'. These separate the low and high speed damping, a simple hole for low and a spring loaded valve for high. The oil weight in conjunction with the hole sets the low speed damping. The rate of the spring and the amount of preload on it changes when the high speed damping comes in and how much effect it has.

I bought a pair of these from PDQ but they're made by Race Tech in the USA.