Ducati 50 SL/1 two-stroke

Ducati 50SL/1 two-stroke

With Phil Aynsley

Think Ducati. Think two-stroke? Way back in the ‘60s and ‘70s the company produced a wide range of two-stroke bikes (also a pair of scooters and 3-wheeled delivery vehicles) ranging from 48cc to 125cc.

Most were cheap, basic transport – but being Italian some models went a step further.

The 50 SL/1 is actually one of my favourite Ducatis. How could anyone not embrace its ‘boy racer’ aesthetics coupled with its diminutive size?

It was released in late 1966 as a replacement for the not quite as over the top 48 Sport. In typical Ducati fashion a ‘standard’ version, the 50 SL, appeared first.

This had the newly designed 50cc two-stroke motor that made 4.2hp and dispensed with the fan-cooling the last model 48 SL used.

A four-speed foot change gearbox replaced the three-speed twist grip change of the 48. The pedal assistance of the earlier motor was also dropped.

The SL/1 used a different head and had a higher compression ratio, which  together with additional porting and 18mm Dell’Orto carb (4mm up on the SL’s) boosted the output to a heady 6hp!

With a dry weight of 58kg a top speed of 80km/h was possible and both low or high level pipes were available.

The most obvious difference to the SL was the styling. A long, narrow tank was fitted that featured very sporty twin filler caps. Together with the short solo seat and exposed front fork springs the look screamed “racer”.

The not quite as good looking SL/1A was released for 1968, which was the final year of production for the model.

As the SL/SL1 were only intended for the domestic market very few have found their way outside Italy.

The one seen here was imported to the US a few years ago and is in completely original condition.