1960 Gilera 175 Sport

In many ways, the Italian motorcycle industry in the 1930s mirrored Britain’s bike makers of that time.

Benelli, Bianchi, Guzzi and Gilera all produced single-cylinder 4-stroke street bikes with various levels of sophistication in the 250 and 500cc classes. But the aftermath of World War II dramatically altered the Italian motorcycle market. Required were miserly, small capacity basic transportation bikes like mopeds and scooters. And while Guzzi and Gilera continued to build prestigious 500cc and 250cc 4-stroke singles into the 1950s (such as the Falcone and Airone from Guzzi, and the Saturno and Nettuno from Gilera), sales in those classes were slow.

Companies new to motorcycle production proliferated: Aermacchi, Innocenti, Agusta, Piaggio, Laverda, Ducati, Parilla, Rumi and more. Motorcycle makers with a background in larger capacity machines struggled. One of the more agile of the heritage manufacturers was Gilera.

Giuseppe Gilera founded his motorcycle company in 1909 at the age of 22 after apprenticing at Bianchi. After World War I, Gilera opened a new factory at Arcore near the Monza circuit, and the company quickly became not only one of Italy’s largest motorcycle manufacturers but was also successful on the racetrack. In the 1930s, the company’s volume production had been based around a range of side-valve 4-strokes.

The Gilera 125

Gilera knew that 4-stroke motorcycles were considered superior to 2-strokes in the minds of the cognoscenti, and so they were able to command a higher price — though they were typically more expensive to produce.

So, forsaking the 2-stroke route adopted by many other early post-World War II makers, Gilera tasked Ing. Piero Remor with designing an entry-level 125cc 4-stroke. But it wasn’t long before Gilera and Remor clashed over the design. Remor proposed a modern OHV 4-stroke engine, while Gilera demurred, favoring a traditional side-valve design. The patron prevailed — though one outcome of their spat was that in 1949 Remor abandoned the Arcore company in favor of an appointment at MV Agusta.

Thus, at the 1948 Milan motorcycle show, Gilera presented an uninspiring side-valve 125cc 4-stroke with a meager 3.5 horsepower giving a top speed of around 45mph. Despite lackluster performance, it gained kudos for miserly fuel consumption.

But the production motorcycle eventually announced at the 1949 Milan show was a 125cc OHV 4-stroke with 4.7 horsepower and a top speed of 50mph — though it carried over some of the features of the flathead version, housing the camshaft and side-by-side pushrods in the front of the engine. In spite of its modest performance, the 125 was a sales success, at least partly because of its frugal 95mpg. Production could not keep pace with demand.

It wasn’t long before a revised 125 was announced, with friction dampers working on the swingarm rear suspension and front-end “parallelogram” girder forks — though production still lagged behind demand. This issue was addressed in early 1951 with the installation of an assembly line at Arcore with an output of up to 1,000 machines per month. Introduced at that time were two new models: the Turismo and Sport. The Turismo featured increased oil capacity in the wet sump and a switch from roller big-ends to plain bearings, while the Sport added greater fuel capacity to 13 liters (3.43 gallons) and increased power to 7 horsepower, giving it a top speed of more than 55mph — without using any more fuel, it was reported.

The 150

Italy’s vehicle excise system of the time allowed motorcycles of up to 125cc to escape registration and therefore taxation. This advantage evaporated in 1952 when registration was introduced for 125cc machines, and new rules prohibited them from using the autostrada.

Instantly, the go-to engine size became 150cc. Before the switch, Gilera is reported to have built 25,000 of its various 125cc machines. The new 150 used the same 54mm stroke as the 125, but with bore increased to 60mm. The 150 was initially available in Tourismo and Sport, each using different front suspension. The Tourismo had the familiar parallelogram girder type, while the Sport introduced a telescopic fork. Both were initially sold with a 3-speed gearbox, though the 150 Sport gained an extra cog in 1953. In the same year, Gilera made available a limited-edition sporting model called the Dimostrazione featuring a bum-stop dual seat, tachometer, “cocktail-shaker” muffler and Monza-style filler cap. 1955 saw the introduction of the Gran Turismo; the Super Sport and Rossa Super followed in 1957. Production of the 150 ceased in 1960 after around 96,000 had been built.

The 175

In 1956, Gilera introduced a 61mm-stroke version of the 150 engine giving 172.5cc. The G175 as it was known was joined by a Gran Turismo and Extra competition model at the end of the year when it was renamed Normale. The Extra incorporated features of the Gilera B300 (a 300cc twin that was essentially two 150s side by side) including its chain-driven primary. For 1957, the Sport was introduced in Gran Turismo engine tune, while the Extra became the Rossa Extra.

Production of the 175 continued into 1960 by which time around 10,500 units had been produced. A revised engine with the contact breaker moved to the left side primary case arrived in 1961 and introduced the Giubileo (Jubilee) model, though it’s unclear which jubilee it was intended to celebrate. Production of the new 175 lasted until 1969.

Jim Bush’s 1960 Gilera 175 Sport

Langley, British Columbia’s Jim Bush bought his Gilera 175 Sport at auction in Las Vegas in January 2019. And though he’s delighted with the bike, it did require some fairly intensive work to get it back on the road. The description noted that “this example being offered has been restored and remains in good condition though after dry storage will require the usual safety checks before running again.”

“That implied that it was a running bike” says Bush, which proved not to be the case.

“The ignition points had been improperly installed with a direct short; the head gasket was blown; and the sump plug had a hole in it, meaning when topped up with engine oil, it would exit to the ground!” Neither has Bush yet succeeded in getting the lights to work.

“The restoration appears to be of the highest level of cosmetic finishing,” he notes. “Externally it is a stunning restoration, correct in every detail. What lies under the shiny covers is an engine that was put back in just as it was prior to restoration. There was no effort to restore the engine, evidenced when I pulled the head to replace the blown head gasket and discovered many years of carbon build up.”

Bush checked the piston, rings and cylinder bore. “Everything looked good and was showing a certain amount of mileage,” says Bush.

The engine’s condition was inconsistent with what happened next: “I was barreling along at full throttle on a quiet back road at around 60mph and it felt like it seized, with the engine suddenly quitting,” says Bush.

Bush pulled the clutch and coasted to a stop. After a quick check over, the engine restarted and ran with no sign of mechanical damage, “no smoke or rattles, it ran just fine,” Bush says. When the same thing happened three more times in the next few days, Bush began to suspect a simpler issue.

“I discovered that the ignition key had ejected itself out of the ON position due to the high-speed vibrations, and only needed to be gently pushed back in to keep it running. The years have not been kind to the brass contacts that keep the key in its place!”

Riding the 175cc Gilera is really a different experience than a full-size motorcycle, says Bush. The limited power means speed preservation and anticipation are the keys. “Compared to my other small tiddler, a 125cc MV Agusta of the same era, the 175cc Gilera is a capable ride. It is easy to maintain 40 to 50mph without too much fuss and it will take on a hill enthusiastically. The low handlebars and sprung seat make for a comfortable ride. The 4-speed gearbox selects easily, and the brakes are very good. Not to mention, whenever you park it, there are always conversations struck up with admirers! Not many people know what to think of it, but they all are taken aback by its stunning good looks.” MC

Cuckoo in the Nest

When Ing. Remor joined MV Agusta from Gilera in late 1949 he could point to an impressive and relevant resume. In 1923, he and Carlo Giannini designed a 4-cylinder, air-cooled SOHC motorcycle engine, with the camshaft driven by a train of gears between the middle cylinders. Giannini and Remor recruited Count Giovanni Bonmartini to their project, producing a complete motorcycle called the GRB. By 1928, and with partial liquid cooling around the exhaust valves, their engine was producing 28 horsepower at 6,000rpm.

Though well ahead of its time, the GRB failed to find a market, and in 1930 the company folded, with Giannini joining Bonmartini’s Compagnia Nazionale Aeronautica. CNA retained the rights to the OHC engine. Around 1934, Bonmartini hired Remor together with racer/engineer Piero Taruffi to further develop the GRB engine. Remor added a second camshaft, full liquid cooling and supercharging.

With 86 horsepower at 9,000rpm, the Rondine (swallow) was a revelation. It beat the Moto Guzzi and Norton factory machines on its first outing at the Tripoli Autodrome in 1935, finishing first and second. Then in 1936, Count Bonmartini sold his company to engineering conglomerate Società Italiana Caproni: the new owners weren’t interested in racing.

Gilera jumped at the chance to acquire the Rondine, while also recruiting Taruffi (and later, Remor). The Rondine gained swinging arm rear suspension, and with further engine development, Taruffi took to the strip and the track, setting a world record flying kilometer speed of 170mph (272kph), and a one hour average speed of 127mph (205kph).

But perhaps the Rondine’s greatest achievement was winning the European Championship for Teodoro “Dorino” Serafini in 1939 after an epic tussle with Walter Rusk on the “blower” AJS V4 in the Ulster Grand Prix.

With supercharging banned after 1945, Remor redesigned the Rondine with a new wet-sump engine, which fitted into a pressed-steel frame with torsion-bar rear suspension via a swinging arm, and girder front fork. Though factory rider Nello Pagani described the machine as “unrideable” when it debuted in 1948, it was good enough for Pagani and Arcisco Artesiani to finish second and third in the 1949 world championship behind Les Graham on the AJS E90S “Porcupine.”

Parting of the Ways

At the end of 1949 Count Domenico Agusta lured Remor, Artesiani and chief mechanic Arturo Magni away from Gilera to his new Meccanica Verghere motorcycle factory. Remor produced a new 500 4-cylinder motorcycle with shaft final drive from a gearbox laid out longitudinally behind the engine and driven by bevel gears. Torsion bar springing was used front and rear, with a girder-style front fork, while the rear was controlled by a pair of swingarms.

With Taruffi in charge of development at Gilera, the Four was fitted with new cylinder heads and bigger carburetors for the 1950 season, rewarding factory rider Umberto Masetti with a world championship. The Four’s frame and suspension were revised, and larger brakes added for 1951. But neither Italian factory team could “approach” Geoff Duke, who took the 1951 championship for Norton. Then, in a move that shocked the British public, Duke defected to Gilera.

Not to be outdone, in 1951 MV Agusta hired 1949 500cc world champion Les Graham. The 1952 MV Four now featured chain final drive with telescopic fork front and swingarm rear suspension. And while the bike was almost right, MV lost its top rider when Graham was killed in a crash at the 1953 Senior TT, and Gilera’s Masetti took the world title. For the next three years, Duke dominated on the Gilera, taking the 1953-55 world championships. But in late 1955, Count Domenico countered, signing 21-year-old Figlio del Vento (Son of the Wind), John Surtees. The result was MV’s first world championship in the senior class, after Duke was sidelined by the FIM for supporting a riders’ strike.

With Norton pulling out of racing in 1956, and Duke absent through injury in 1957, Gilera’s parting shot in 500cc racing yielded a world championship for Libero Liberati. Then, at the end of the 1957 season, Gilera, Moto Guzzi and FB Mondial all closed their race departments. That gave MV the pick of the best riders of the next two decades: Surtees, Hailwood, Agostini, Hocking and Read, racking up 17 consecutive 500cc world titles.

Whether MV would have been as dominant had Gilera stayed in the championship makes for interesting speculation. — RS

Originally published as “Just Right! Gilera’s Goldilocks Bike” in the May/June 2023 issue of Motorcycle Classics magazine.