The "new" mini-bike X-90 is a 90cc 2-stroke 4-speed model. Looking back at 1972 clearifies the "new" in all this... the MC-65 (Shortster) of the Aermacchi-Harley-Davidson era was clearly the basis of the X-90. Wheels, front-fork, mudguards etc are identical to the Shortster and also the frame is a look-a-like of the MC-65. The new engine comes with a seperate oil-tank which is driven on the right-side by the crankshaft. Also no more self-mixing the oil and the fuel. AMF-Harley-Davidson was very clear about use they aimed at in their promotional adds: leisure. Production was from 1973 till 1974 with probably model manufactured in 1975 still. Total amount of models manufactured: 16,837. They sold new in the Netherlands in 1973 for f 1.595,- and in 1976 (more then one year old) for 1.995,-

The Z-90 was marketed for lovers of a somewhat bigger mini-bike. According to the promotional add it was to be a model that was suited for on-and off-the-road adventure and even with an extra passenger! The engine is identical to the x-90: bore and stroke= 48x50 and a compression-rate of 1 : 9.22. The electrical system is changed, it's now an AC system, flywheel with coils on the left crankshaft-tap and a voltage-regulator which is also used on the SS and SX 350. The frame was based on the SR 100, also known as the Baja in the Aermacchi-Harley-Davidson era. The production of this model was from 1973 till 1974, with some in 1975 and there were 17,974 models manufactured. They sold new in the Netherlands for f 1.695,- in 1973, 1.895,- in 1974 and in 1975 (more then one year old) for 2.195,-.

Source: Aermacchi-De Gevleugelde and AMF-Harley-Davidson 1972-1978 by Jaap de Jong