What was the Birel Drag?

Columns: Legendary kart
The Birel Drag was introduced in 1968. Birel invested heavily in the development of that particular chassis which impressed with its innovative characteristics especially on bumpy street circuits from the first time it appeared. Text: E.Barbiani – Photos: A. Scudieri

The triangular shaped frame owed much of its inspiration to the Swedish Robardie kart. The Drag was easy to handle and much faster compared to its rivals at that time. The agreement between Birel and the Italian Federation also contributed to the popularity of the Drag chassis. Every year back then the Federation made agreements to have one or more manufacturers provide discounts on the price of new karts to encourage people to take up karting. A brand new Drag sold for 160,000 Lire which was a little more than an average monthly salary at that time. 

The tubes used for making the main Drag frame were all 30 mm diameter. The wheelbase was 1010 mm, the rear track which was not adjustable measured 800 mm and the front track was 740 mm. Axle bearing supports were integrated in the end part of the two longitudinal members that then joined up at the front of the kart which gave the chassis its characteristic triangular shape. A great advantage for this chassis was the fact that the driver could sit in a rather stretched out position which provided a low silhouette and therefore a lower centre of gravity for the kart.

Because the kart fame had the particular triangular shape a small transmission rod was required between the steering column and the two track rods. When the longer than normal steering column was turned it made the front part of the transmission rod turn to the right or to the left pivoting on a bearing placed in the centre which moved the track rods that in turn moved the spindles. The tubes that supported the spindle 'C' brackets were placed transversally and angled upwards from the main chassis rails. They were also reinforced by additional pieces of smaller tubing forming a narrow triangle. Such an arrangement made the chassis very flexible and suitable for bumpy street circuits. 

The fuel tank was an elongated shape which was made to fit below the steering column and was made of glass fibre. Every part of the kart was fabricated meticulously and special attention was given to details such as the demountable seat supports. Such attention to detail made the Birel brand name stand out everywhere on the kart. The mechanical brake calliper worked on a thin disc and was attached to a bracket which was welded onto the left longitudinal member of the chassis just in front of the rear live axle. 

The rear wheels on the Drag were special. The rims were cast from aluminium and the rear units had a particular 'single nut' lock system. The hub was slipped onto the axle and locked with a nut; the rim was fitted onto the hub making sure that the internal edging mated with the edging of the hub and then the knock-on nut was screwed on. To avoid any problems or the risk of the hub thread unscrewing, the screwing up direction on the left hand side and the right hand side was different and it was opposite to the rotation direction of the axle. However, it was one of the most impractical systems because to fit and remove the wheel you had to hammer on 3 spigots and this often broke them. The rear rims were fitted with standard width 410 x 350 x 5 Carlisle tyres of that time and the fronts had a similar size tyre but narrower. The front rims were also aluminium but followed conventional design.

At that time karts were raced on hard compound tyres. At the end of a race day the experts would remove the wheels and tyres which were then machined on a lathe to reduce the shoulder heights because the tyres tended to wear in the middle of the tread.  Considering that two sets of tyres would last a whole season poor grip around the turns was well justified due to the tyre’s long use!

A Parilla HF17 was mounted on the Drag in the article; the engine was recognisable by the fact that the cooling fin just above the exhaust was slightly longer compared to the others. The engine which was made by IAME in 1968 was very similar to its predecessors the GP15 and MK16. A fuel pump was fitted to the front of the engine which was activated by the pressure inside the crankcases. The pump supplied fuel to the Dell'Orto carburettor which featured a return pipe back to the fuel tank because the pump which was also made by Dell'Orto was too efficient. 
The end of the exhaust expansion muffler had a long rolled conical outlet hole which was protected by an extension to the rear bumper in case of collisions. The engine was fixed onto an alloy base which was clamped to the two tubes that were located at the side of the seat and tilted upwards towards the rear axle. In some of the early versions of this chassis made in 1968 a flat steel plate for mounting the engine was welded to the main chassis rail adjacent to the seat location. The plate featured slotted fixing holes to allow chain tension adjustment.
The Drag chassis made its international debut on Sunday the 4th May 1969 at Vevey in the hands of the Italian National Team made up of Nino Vernieri, Pietro Necchi, Vincenzo Saitta and Gabriele Gorini. The race didn’t go well for the team; under pouring rain the Italians only managed to defend their positions. Vincenzo Saitta from Rome achieved the best result out of the Italians finishing seventh overall. On the way back from that race Saitta, who was just sixteen, sadly lost his father in a fatal road accident.

The Italian National team improved with each race they entered, but it was unable to compete for the top places at the 1969 World Championship. Nevertheless they made up for it that year at the first round of the European Championship held in Jesolo where Gabriele Gorini finished first. 
In addition, at the 1969 Italian Championships, the First, Second and Third Classes were won by a Birel Drag. Pietro Necchi, Eugenio Piazza and Antonio Sardo respectively were the winners. However, the fact that the Birel Drag did not sell well at international level was concerning for Umberto and Oscar Sala, so much so, that they started working on a brand new chassis, less complicated than the Drag, which was named the Targa and was destined to bring untold glory to the Lissone based company.

Francesco Nanni, Jarno Trulli’s mentor, was a driver who won a lot with the Drag chassis when he raced karts. Francesco said, with a nostalgic voice, how good those days were and how easy it was to begin racing karts then. He clearly remembered buying a new Birel Drag chassis and taking advantage of the Federation’s promotional discount. 

Special thanks is extended to Matteo Chiarello from Vicenza, Italy, a vintage karts enthusiast who kindly provided the Drag for the article and also to the Polenta and Motori track located near Vò Vecchio in the Province of Padova which provided the backdrop to the pictures of the Drag taken during the circuit lunch break.

 

Created by: cggiuliano - 10/04/24

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