THE MOTO GUZZI 500cc V-TWIN
A Grand Prix contender for twenty years
Moto Guzzi’s 500cc V-twin was the longest-lasting Grand Prix contender of all time. It competed with success in top-level international races for two decades, winning its first race in 1933 and its final World Championship GP race in 1953. Its only rival in the longevity stakes was the equally famous Manx Norton but the British bike’s single-cylinder engine underwent a significant upgrade from its single overhead-camshaft valve operation to a twin-cam cylinder head in 1937, whereas the Guzzi retained the same engine format throughout its racing life.
Its engine was a unique 120º V-twin four-stroke with single overhead-camshaft valve gear and it pioneered the format of a wide-angle V-twin engine installed lengthways in the frame – doing so some forty years before Ducati’s 90º V-twin appeared in the early 1970s. The engine had a smooth power delivery and plenty of it. On twisty circuits or in bad weather, this allowed the Guzzi to defeat the much more powerful but much less tractable supercharged bikes from Gilera and BMW in the 1930s and the higher-revving four-cylinder racers from its Italian rivals, MV Agusta and Gilera, in the 1950s.
It made its racing debut in October 1933 in the Italian GP held at Rome’s Autodromo del Littorio which was located within the city’s Urbe airport and it was almost a winning one. Moto Guzzi team rider Guglielmo Sandri finished second but this was after he had crashed and remounted. Given that setback, it was a promising debut indeed. Two months later, Sandri’s teammate Amilcare Moretti recorded the new bike’s first victory in December’s Naples GP.
In 1934, Irishman Stanley Woods joined the Guzzi Works team for selected races. The former Norton works rider was already a six-time TT winner but had become disillusioned with the performance of the British singles and had begun riding the more powerful 500cc V-twins of both Moto Guzzi and the Swedish Husqvarna factory on a race-by-race basis.
The Irishman won his first race on the Guzzi in April 1934, this being the Spanish Grand Prix on Barcelona’s Montjuic Park circuit. But despite the win, Woods nicknamed the bike the ‘Monster’ because of its reportedly evil handling and chose the Husqvarna for that year’s Isle of Man TT. He may have wished that he persevered with the Guzzi, however, as he got no higher than second place before running out of petrol.
Unlike Woods, Guzzi’s new Italian star Omobono Tenni was unperturbed by the V-twin’s behaviour and he won the 1934 Italian GP in Rome as well as taking the 500cc Italian national championship. This was the start of a long run of successes for the Guzzi in the mid-1930s.
Not only was the bike fast, it was also superbly reliable and this was proved in 1934 when one of the GP racers was fitted with a speedometer, toolboxes, silencers and a rubber bulb horn to turn it into a road-legal machine that took Terzo Bandini to victory in the 1934 Milan to Naples marathon at record speed. It was the start of a period of the Moto Guzzi V-twin’s domination of the Italian long-distance road races.
Bandini duly repeated his 1935 success, but this was in the 1937 sidecar class using a V-twin fitted with a Longhi sidecar. Meanwhile, Omobono Tenni underlined the solo version’s long-distance racing capabilities by winning both the 1935 and 1936 editions of the same event.
Guglielmo Sandri made it four in a row in 1937, this time in a 1,283km marathon race, which by then ran further south down the Italian peninsula to Taranto. This race saw eleven of the Moto Guzzi twins finish in the first 15 places!
Away from the roads during the mid-1930s, the Moto Guzzi racers won regularly on the race tracks of Europe. Successes included winning the Italian GP (by then at Monza) on two more occasions in 1935-36, and breaking the 150kph average speed barrier for the first time. This was on the banked Monza circuit using a bike that was fitted with an engine using enormous megaphone exhausts that extended past the rear wheel. Top speed was just over 180kph (112mph-plus) with the engine running on 50/50 petrol/benzole and with an 8.5:1 compression ratio.
But the victory which established the Guzzi V-twin as the leading 500cc bike of its era was Stanley Woods’ remarkable win in the 1935 Isle of Man Senior TT. With the bike’s handling issues now sorted to his satisfaction, he led Jimmy Guthrie’s works Norton home by just four seconds after a thrilling race in rain-lashed conditions. In doing so, he averaged 84.68 mph for the seven-lap 264-mile race.
Woods also won the Lightweight TT the same week on a Guzzi 250cc single, to complete what was a unique double in that era.
By 1951, the Moto Guzzi 500cc V-twin was developing 52bhp at 8,000 rpm and at Monza was timed at 210kph (130mph) – some going for an 18 year-old design! It was this, combined with the bike’s dependable attributes of easy handling along with a smooth power delivery, which saw Fergus Anderson able to trounce all the rival works teams to win the 28-lap 127-mile 1951 Swiss GP in wet conditions on the Bremgarten track, with its notorious cobblestoned surface. Enrico Lorenzetti further emphasised the easy-riding attributes of the Guzzi to take third place.
Two years later, after the bike had been pensioned off from its role as a factory team racer, Anderson also raced one to victory in the 1953 Spanish GP. That was the final success for the Moto Guzzi V-twin in an amazing two decades of Grand Prix racing.
Words: Bruce Cox
Information and Images provided by The Motorcycle Files
Recommended Reading (Available exclusively via Amazon)
MOTO GUZZI GRAND PRIX CLASSICS
Author: Alan Cathcart
(Part of the Great Racing Motorcycles series published by The Motorcycle Files)
THE MOTO GUZZI 500cc BICILINDRICA GRAND PRIX RACER
(An e-book by Alan Cathcart published by The Motorcycle Files)
