"Like racing a demented ball bearing" - Lambretta Monotubo

Lambretta Monotubo

Ferdinando Innocenti commissioned aeronautical engineer Corradino D’Ascanio to design an affordable and clear two-wheeled automobile to supply post-war transport for the home Italian market.

Lambretta Monotubo

Carradino devised a stamped metal spar-framed machine that probably took inspiration from the Cushman scooters utilized by American troops in the course of the conflict.

Built-in leg shields, an open centre part and an enclosed gear closing drive from the motor situated underneath the seat (quickly to be enclosed by panels within the second mannequin) all labored to satisfy the transient for a clear machine that girls may simply journey in skirts.

Nonetheless, Innocenti wasn’t pleased with the spar body design, as he most well-liked it to be constructed from tubular metal, which he may supply from his personal steel-tubing manufacturing facility established in Milan in 1931.

It had been largely destroyed in the course of the conflict, and he wished to revive it via the manufacture of the brand new scooter design.

Carradino left (and took his design to Enrico Piaggio – who produced it because the Vespa from 1946), so it was fellow aeronautical engineers Cesare Pallavicino and Piero Luigi Torre (who was accountable for the engine and establishing the manufacturing facility for mass manufacturing) who accomplished a revised design.

The primary Lambretta scooter, the A mannequin (also called the 125M), went on sale in 1947.

Being Italian firms, it wasn’t lengthy earlier than Piaggio and Innocenti have been concerned in each racing and pace document makes an attempt to advertise their manufacturers.

Scooter racing had grow to be a giant deal in Italy by 1950, and Lambretta’s mainstay was their 125 cc Bitubos (a reference to the 2 megaphone exhausts exiting the rear of the only cylinder 2-stroke) launched in 1951. Two streamliners have been additionally constructed and set a World Pace Report of 201 km/h the identical yr.

The racing Bitubos featured the carburettor dealing with the entrance and benefiting from ram-forced induction at speeds above 100kph. 4-speed gearboxes have been used, as was the newly developed torsion bar rear suspension. 12 or 14-inch strong alloy wheels have been fitted, relying on the circuit.

4 Bitubos have been despatched to Germany to be raced underneath the NSU banner (as they have been licensed to construct and market Lambrettas) in February 1951. These had barely totally different frames and bodywork to the Italian Bitubos.

Each the Italian and German machines have been raced extensively and have been fairly profitable. The destiny of the “NSUs” shouldn’t be recognized, however they have been probably despatched to South America.

The Italian Bitubos have been transformed to a extra typical engine configuration with a single forward-exiting exhaust and rear-facing carburettor – thereafter being referred to as Monotubos.

These have been bought to personal people, one being the Australian Innocenti SG consultant, Sam Jamieson. Two bikes with engine numbers 4S and 5S arrived in Sydney in November 1951 and are believed to be the primary two Bitubos constructed and raced in Italy by Ferri, Copeta and Poggi within the first half of that yr.

Jamieson had organized for 39-year-old Innocenti manufacturing facility mechanic Renato Bini to work on the bikes, and he duly arrived in January 1952 (and stayed in Australia till he died in 1975).

The Monotubos’ first race in Australia was the Mount Druitt TT in March 1952, the place Jamieson and John Seary rode them to 1st and 2nd locations within the 125cc class! At Bathurst, nevertheless, Jamieson may solely end 2nd to Maurice Quincey. Bert Flood on a Mannequin B racing Lambretta was third.

Of the ten races the bikes contested throughout 1952, they scored 9 firsts and a second. Many extra victories have been obtained throughout the next two years till the bikes have been bought to Eric and Harry (Jnr) Hinton on the finish of 1954.

Bini ceased to fettle the machines right now. The Hintons steadily raised the compression ratio from the usual 7:1 (9:1 for alcohol), which gave a high pace of just below 150 km/h, to 14:1 on a 15% nitro-methanol combination.

This resulted in a rise in high pace to virtually 185 km/h! Reliability suffered, nevertheless, with the bikes being arduous to start out and having holing pistons. Eric did end 2nd within the 1955 Mount Druitt GP, forward of Kel Carruthers.

The Hintons bought the bikes again to Jamieson after 12 months, who bought them to Kevin Roydon. At about this time the unique bodywork on the bikes have been changed by dustbin fairings (and for the 4S machine a decrease becoming tank), totally different handlebars and many others, all made by Lindsay Smith.

The bikes continued to put nicely, ridden by quite a lot of riders, together with Kel Carruthers, who completed second on the 5S bike on the 1957 Australian TT at Phillip Island.

The bikes have been then on-sold quite a few occasions, with the final document of the 5S being raced at Calder Park in March 1962 and 4S in 1964. The 4S bike is being restored in NSW.

I photographed 5S in 2013, and it nonetheless has all of the modifications performed to it over its racing life, notably the additional body tubes added between the steering head and tank assist to “shut” the open scooter body. The unique tank mounting lugs on the body have been lower off, and the tank now sits decrease. Additionally, the bars, exhaust, carburettor, and some different objects usually are not unique.

The unique bodywork has lengthy since been misplaced. A few interval B&W pictures present one of many NSU Bitubos and Bob Jamieson at Bathurst (most likely) in 1952 to offer an concept of how the machines initially regarded.