S p e c s: NK 9.220.001

Dates unknown
engine: single cylinder, air cooled 2-stroke
induction: rotary disc valve
bore: 55 mm
stroke: 51 mm
cubic capacity: 121.17 cc
compression ration: 9.25: 1
bhp at rpm: unknown
lubrication: 2% oil
transmission: 4 speed constant mesh
1st gear: 1: 14.74
2nd gear: 1: 9.80
3rd gear: 1: 7.06
4th gear: 1: 5.31
clutch: wet - multiplate
carburetor: Spanish made Dell'Orto SHB 19/19
main jet: 78
slow running jet:
main air bleed:
starter jet:
ignition: contact & breaker
ignition timing: 19 degrees BTDC
breaker gap: 0.3 - 0.5 mm
voltage: 6V
wheels: 10"
tires: 3.00 x 10"
max speed: 56 mph / 90 kph
weight: 172 lbs / 78 kg
125NK links:

This bike is very similar to the Italian Primavera, but has weird differences, such as the more recent headset type, the carb and coil are both located under the seat, and it is 6V but has points. Thanks to Sandro Vanetta for the images.