Back in March, Royal Enfield pulled the plug on one of its longest-running engine platforms — the 500cc single. The big single first came into existence in the mid-1920s and leaves behind a legacy that will not be forgotten any time soon.
The very first Royal Enfield motorcycle went on sale in 1901, but it was only in 1927 that the company launched its first 500cc-single — the Model 500 — costing £52 (the equivalent of around £3,290 or ₹3.15 lakh today!). Two years later, the company showcased the Model 505, but it was in 1930 that some rather monumental steps were taken in engine design.
In September 1932, Royal Enfield’s factory in Redditch came up with the iconic Bullet. It featured the new LF 500, a high-performing unit with a four-valve head that produced 25hp, just 2.6hp less than the 2019 Classic 500. However, the company’s experimental works department knew it was capable of more, and so a racing kit was offered with a higher compression piston and a straight pipe exhaust. The result — 29hp!
In 1934, two specially-prepared iterations of this motorcycle also took part in the Isle of Man Senior TT race, but unfortunately, neither managed to finish. The following year, however, the same machine, piloted by Cecil Barrow, finished the race in 8th place, averaging an impressive 73.94mph (119kph).
In 1935, RE’s 500cc engine adopted a unique three-valve setup, with the engine rockers and valve gear now fully enclosed, minimising oil leaks. This engine was short-lived though, as the three-valve setup saw power go down from the previous iteration. So, Royal Enfield brought back the four-valve mechanism with the 1936 JF 500. The J2, an iteration from this period, was also commissioned by the British Royal Air Force in the Second World War.
The post-war era
In 1959, the engine was redesigned to deliver better performance, with test runs claiming that the bike was capable of 91mph (146kph)! This engine was also the last big-single to be manufactured at the Redditch plant, its production ceasing in 1962.
By 1956, operations had begun at the Tiruvottiyur factory in Madras, where 350cc Bullets were manufactured and exported. They were a huge hit locally as well as in international markets, but international demand moved in the direction of more powerful motorcycles. Enter the 1989 500 Bullet, the first 500cc Royal Enfield to be manufactured in India. It featured a re-engineered version of the Redditch-made 1956 JS 500 with more recent technology like coil-ignition and alternator electricals.
The UCE 500 was the most significant step by the company with its big-single, featuring a gearbox that was now integrated with the crankcase, hydraulic valve lifters and fuel-injection — all firsts for a Royal Enfield. The engine was used in multiple models like the Thunderbird 500, Bullet 500 and the Classic 500, which went on to become the bestselling Royal Enfield 500 ever.
A legend in the Indian racing scene, G Subhash Chandra Bose, aka Bullet Bose, had a couple of interesting tales to share. He told me that he felt the fuel-injection system did not fully extract the capabilities of the UCE, so with his team at UCAL Fuel Systems, he began developing a carburettor. The result was the modern-day Bullet. What started out as a rather straightforward conversion, soon saw numerous bench tests, the realignment of the carburettor mounting points and even the fuel tank, to better accommodate the carburettor. The conversion was so efficient that it even allowed for one of the two catalytic converters to be removed, resulting in better performance.
The 500’s demise ultimately came down to strict emission regulations, but also due to the fact that the Classic 500 was priced uncomfortably close to the new 650s. Royal Enfield is now creating some thoroughly well-engineered products and there is a brand-new 350 platform set to debut very soon. The 500’s era has finally drawn to a close and we are unlikely to ever experience another raw, characterful, and yes, far-from-perfect engine like it. The 500 will always be a significant and dearly beloved milestone in the company’s 119-year-long journey.