Perfectly Formed KTM 50 GS 1972

The 50cc models marketed by KTM were always billed as utility motorcycles for children, despite having participated in off-road Regularity races from 1964 to 1970, with the Sachs powered Comet. These bikes were built in very low numbers and were entrusted to

the riders only for the race event. The engines were developed by Sachs under the request of KTM and were practically identical in all respects to the engines that were used in the Hercules. In those years there were countless battles between Puch, KTM, Hercules, Simson and Zundapp.

KTM 50 GS 1972

Words and photos by Paolo Sala

the riders only for the race event.

In 1970, KTM completely abandoned the Comet 50 class project to devote itself to the development of the new KTM offroad machines of higher displacement, which had worldwide success thanks also to the agreement signed in 1968 with John Penton. The retirement of the glorious Comet 50 GS heralded the start of the construction of a new model, the first model of which was deployed straight away in the Valli Bergamasche event, as if to symbolically represent the passing of the baton.

It was an all-Italian experiment carried out by Mainini - a frame from the ‘71 model, hastily adapted to accommodate the smallest 50cc engine (a classic short-stroke Sachs with a sixspeed gearbox) by means of small connecting brackets.

Led by Mauro Miele, he concluded the entire test and finished ninth in his class. The same bike appeared in other national races but did not shine in the rankings - third at the Arona Trophy on 22 October, and only sixth at the Fulvio Norelli Trophy on 12 November. After this first debut, which was a bit simplistic and all very limited by resources, a new much more refined prototype followed, developed directly in Mattighofen.

This prototype, of which we have been told is one of a dozen specimens, is the bike that we present to you in this photo shoot.

Compared to the bike built in 1971 by Mainini, on this new 50cc you can see greater attention to detail and that the frame is more wrapped around the engine, thanks to the use of smaller diameter tubes.

The bike follows the look of the bigger sisters, simply softened by the small tank. On the first examples, different types of Ceriani forks were tested, but preference was given to those used on the larger 125cc models with 32mm tubes and four-bolt plates. The high muffler that crossed the frame under the seat was the classic Sachs of dimensions suitable for the small displacement. Even the tires (front 2.50x21 and rear 3.00x18) were adequately reduced.

The bike in this article was spotted by an Italian enthusiast during a visit to a vintage motorcycle market in Austria. Unfortunately the head, piston, cylinder, carburetor and muffler had already been sold separately and the bike was ready to be dismembered and sold in pieces. In reality, the buyer (and now current owner) immediately understood what it was and quickly concluded the negotiation to take all that remained. He also asked the seller if they knew the contact details of those who had purchased the top end, but you know what

it’s like at the flea markets - you see some parts, you haggle a bit, you pay and then you leave without leaving your details. The Austrian seller had used this KTM 50 for off-road races at their local championship and also had the original documents, from which it can be proven that the bike was put on the road in 1972.

The engine is the classic Sachs short stroke but in the seven-speed version. The forks are the 32mm Ceriani versions of the older sisters (100 and 125) and the bike now sports Koni shock absorbers (perhaps Girlings were installed originally). The brakes are original items from KTM but with a smaller diameter and the front was built specifically for this model. The original steel rims have been replaced with Akront aluminum rims as they are lighter and more beautiful. The frame is very similar to the 125cc model but all the cradle tubes are smaller in diameter and the proportions are also smaller, so much so that the tank looks like it came from a mini bike but in reality it is just a little shorter than the one used on the bigger models.

The discover y of a motorcycle used for a long time at various events over the

Insets: 1. Slim and trim. 2. Classic through the frame exhaust. 3. Airbox had just enough space. 4. Ceriani 32mm forks. 5. Frame tubes are very slim. 6. Rear tyre was 3.00x18, front was 2.50x21.

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