Enfield, the thump machine

The bike has a 500cc Unit Construction Engine and 27.2 bhp power output being fed through an electronic fuel injection system. It is available at Rs. 1,82,571 (on-road price for Mumbai).

Royal Enfield chief executive officer Venki Padmanabhan at the company's Chennai factory. The company sold 74,600 motorcycles in 2011, a 40% increase, all made at its 57-year-old factory in Chennai, and is spending $30 million this fiscal year in a push to double capacity and upgrade manufacturing technology.

The Classic Chrome 500. The new Classic series is driving the company's growth in a crowded and fast-expanding Indian market where 10 million motorbikes were sold last year.

A worker assembles an engine inside the plant. The revolutionary Unit Construction Engine has replaced Royal Enfield's antiquated cast iron engine, boosting acceleration, performance, mileage and reliability, and reducing emissions.

The Thunderbird Twinspark was the first model to feature the new engine.

A worker paints a fuel tank at the factory. Purists still come to the company looking to buy a bike with the old engine, but they have to go to the second-hand market as production ceased in 2010.

A worker fixes a number plate on a motorcycle. The company rolled out its first motorized bike in 1901 and entered the Indian market in 1949, where the Bullet, now in its 80th year of manufacture, became a staple on the country's roads.

The Bullet 500 is the longest running model in continuous production.

Motorcycles on an assembly line. The company sold just 3,200 bikes overseas last year and is looking to expand its export markets on the strength of its upgraded engines.

A worker pieces together a bike at the plant.

Along with the 500, the Electra happens to be one of the most sought after models in the stable.