1981 – In 1981 the last TF1 release, produced with the capacities 125, 175, 240, 250, 280, 347, 370 and 440 cc, was completely coloured in orange, as the official bikes of the previous year.
The most powerful SWM version, the 440. equipped with a Bing 36 mm carburettor, released a power of 47.7 horses at 7.250 engine leaps.
The plastic tank contained an in-built tool case whose cap was fixed through an elastic with three jag, the saddle had a more squared design and the front mudguard carried a big airing grid to improve the engine cooling.
Corte and Cosso, Compact shock absorbers were definitively adopted on the rear axle, so that the two small plates used to fix the separate trays of the old shock absorbers were removed.
Although the frame kept its basic implant, it kept on evolving adapting itself to the newer and newer design schemes from 1979 to 1981.
The most visible changes occurred in the tube section, slightly decreased, the joint of the front cradle on the central rod, the front mount of the engine which was no longer direct, but was mediated by two small aluminium plates.
The most important new event was the introduction of the off road model MK 50 and/or80 GS production which was equipped with a brand new modern and highly performing frame, which resembled the schemes of the elder TF1 sisters, putting aside the old fashioned Silver Vase models.
The racing version of the 80 GS model, was equipped with the Minarelli PS radial engine with short run; carburettors were Dell’Orto PHBH 26mm for the GS 50 and 18 for the MC 50 and 30 for the MC and GS 80.

During the season the newest version of the racing P6 was adopted, it has an overhead cooled with water and a small radiator located below the tank.
Marzocchi feather 32mm with forwarded gudgeoned shock absorbers were adopted and on the back Corte and Cosso Compact series shock absorbers, but smaller-sized than the ones adopted on the TF1 models.
All models carried Akront rims green stamp, conic 125 mm Grimeca hubs with a floating rear hub.
An aluminium big fork was introduced on the cross models which had two arms made of two printed shells soldered on two big plates.
The most performing frames of the TF4 cross series laid the basis for the preparation of the bikes for the official bikers.
If compared to the cross version, you could notice the presence of a kickstand, a back part for the fastening of the back mudguard and bigger dimensions, and a big aluminium fork lightly different, of course further to the electrical implant and the silenced exhaust.
Marzocchi 35 mm axle gudgeoned forks Piffero and a couple of AG6 Marzocchi, on the rear axle.