1973 – The new season started under the best omen thanks to the further improvement of the entire range.
Although the basic structure was confirmed, there were a few changes. As the engine was moved back and had new attachments which were based on the big fork on the back, the distance between the pinion and the pin itself could be optimized; the engine was bolted on the cradle directly through two small plates on the front.
Also the foot rests were moved back, thus improving the attitude and the riding position.
The saddle was higher and more comfortable and was finished with a new mud-guard, which had more soaring lines and did not have the featuring step under the saddle.
Two reinforcing moulded and punched small plates were placed at the crossing of the link studs which joined the forked pin to the breast bands under the main tube rod, so they stood for the third engine attachment which was bolted to them through two small rods and it also offered an attachment to the fixing tank springs. The tank itself was refined with the base colours, for the metal version and it hallowed to host two knee cases.
During that season the top model, ES, featured a big narrower back fork and Marzocchi with 35mm stems, alloy rims and gas shock absorbers on the back.
Three different versions of the same models, that is the cheapest called Regolarità, the intermediate called Six Days ER (Elaborazione Rivolta) and the top, called Six Days ES (Elaborazione Sachs) were manufactured in order to take profit from large production anyway keeping the main structure and 90% of the components constant.
The differences made at the beginning were soon overcome because the SWM  technicians soon became skilled and experienced in elaborating the engines directly and successfully, but the three different variants went on existing on the market.

As far as competitions are concerned, after having spent a year achieving second ranking, 1973 was a year rich in successes and SWM was often on the first stage of the stand.
Gino Perego’s overwhelming supremacy in the 50 class of the Italian Championship led the competitors to be neglected and the youngest to be very enthusiastic.
The success reached in the FMI Trophy was even double as Bonantini won the 50 class and Adriano Rosa won the 100 class, while Gian Luigi Petrogalli ranked 2nd in the 125 class.
Pierluigi Rottigni stepped into the limelight too for the entire season and ended both the Italian Championship and the European Championship in the 125 class ranking second, but his extraordinary victory during the Valli Bergamasche (23rd 24th June) left no doubt on his great skills and his motorbike potentials as he defeated Gritti’s Gilera and Witthoft’s Zündapp.
Pierluigi Laureati ranked 3rd in the 100 class always in the Valli Bergamasche competition.
The team Italia B (SWM Mercatelli, Laureati, Radici, Rottigni ) ranked 7th out of 25 competing teams during the US Six Days in Dalton, Massachussetts (17th – 22nd September).
SWM’s positive results were underlined by the four golden medals won by Pierluigi Laureati (SWM 100), and Gianluigi Petrogalli, Secondo Mercatelli and Pierluigi Rottigni (SWM 125).