1982 – In 1982 the final chapter is written in the story of Frigerio-Puch, whose engine had now come to the end of its long and glorious existence.
Starting a decade earlier as a small air-cooled 50cc it slowly evolved, at its most extreme, into a water-cooled 80cc. Further than this they could certainly not develop and the lack of a solution to this problem dictated their progressive and definite exit from the scene.
Puch's story did thus not go much further. It limped along for a few years until it was bought by Fiat-Piaggio who finally closed the company down in 1987.
To compensate for these losses the Frigerio-Rotax motorcycles suddenly regain momentum in 1982 thanks to the new engines being produced by Rotax. The model range is extended to include a 350cc and includes the new four strokes.
Purely  due to custom duties the 350 was assembled in duplicate engine capacities of 348cc (stroke 66 and bore 82) and 368cc with 84mm pistons.
Apart from this small detail, 1982 will always be remembered as the best season for Frigerio-Rotax thanks to the surprising achievements of Edi Orioli in the 125cc class during the Vallei Bergamasche (Clusone, 19/20 June) where he qualified 2^nd during the first day and 1^st during the second.
In the 175cc class the best performance was achieved by Mario Valsecchi, 4^th on the first day and 7^th on the second. Excellent also the 1^st place achieved in the four stroke division, on both days of the Junior Trophy, by the great Bruno Birbes.

1983 – From 1983 the Frigerio brothers abandoned the 80cc class and the story continues for a few more years, during which Frigerio-Rotax continues to hope that the tide will turn and that they will be able to bounce back from the commercial woes which are dogging the entire sector.
Like many other popular manufacturers, Frigerio-Rotax was also heading into the sunset and one of the most evident symptoms was the progressive thinning out of the field of manufacturers in competitions, despite the continued development of new technology and adopting the most advanced alterations like a single shock and disc brakes.
The last few years of production concentrated mainly on the larger engine capacities.
In 1985 the new four stroke Frigerio-Rotax were presented in three different versions:
GS 350 F4T (79,5x70,0=347cc) 27 hp 7.900 rpm, four valve single cylinder with 5 speed gearbox
GS 504 F4T (90,0x79,0=502cc) 30 hp 7.700 rpm, four valve single cylinder with 5 speed gearbox
GS 560 F4T (94,0x81,0=562cc) 31 hp 7.600 rpm, four valve single cylinder with 5 speed gearbox followed soon thereafter by the GS 600 HWE, also a four valve single cylinder with 5 speed gearbox.
The best rider was Luigi Medardo who showed himself capable in the 250cc class and among the privateers special mention should be made of Andrea Scandella, 500cc class and Claudio Zanoletti, 4 stroke class.
During 1986 once again Luigi Medardo distinguished himself with a 3^rd in the 250cc class at the Six Days of San Pellegrino-Selvino (8/13 September) symbolically coming full circle.
In 1987 the time had run out for these beautiful motorcycles and what happened thereafter is not worthy of mention as it no longer deals with enduro racing, but with the gradual disappearance of the last privateers and the bureaucracy dealing with the dismantling of all activities.