Royal Enfield's New 650 Twin

Royal Enfield, unveiled its first modern twin-cylinder engine at its new Technology
Centre in Leicestershire, England, today. This new 650cc, air cooled parallel twin will power the
newest generation of Royal Enfield motorcycles.

The core idea behind the modern 650 twin engine was to develop a global platform that would
carry the Royal Enfield legacy and character into modern context. The engine has been designed
to offer the right balance between power, torque and usability to ensure a smooth and
approachable riding experience. It will offer broad spread of torque which will make the
motorcycle easy to ride without frequently shifting gears.

The new platform is a 4 stroke, single overhead cam, air-cooled, 648cc parallel twin cylinder
engine developed by Royal Enfield’s UK Technology Centre and Chennai teams. Precisely
engineered to be able to accelerate and deliver higher power and torque at lower RPMs, this
new engine has an output capability of 47bhp and 52Nm torque. This makes the ride
experience hassle-free and smooth.

A highly refined engine, with true highway capability, the 650 twin engine has been developed
to excel across a wide range of real-world conditions. Classically styled, the engine has been
designed to achieve a high level of modern refinement. The twin pipes and the cooling fins on
the classic air-cooled engine render a visually beautiful impact.

The engine maintains an under-stressed 9.5:1 compression ratio and the fuel injection system
ensures that smooth, accessible power is available at all times. The focus of the development
was on giving adequate torque, spread broadly throughout the rev range so that riders can
tap into it instantly at anytime without the need for excessive shifting. As a result the engine
feels fun, potent, and easy-to-use. Making this possible are a number of elements, starting
in the very depths of the engine where there is a single-piece forged crankshaft (a first for
Royal Enfield) which ensures strength and the ability to handle the twin’s torque. This
crankshaft uses a 270-degree firing order, which gives a high degree of character to the
engine’s power delivery. Also, thanks to the use of a balancer shaft, unwelcome
vibrations have been eliminated.

The motor retains Royal Enfield’s ‘air-cooled’ engine legacy, which lends to a simple, cleaner,
more elegant look with fewer components and less weight. It ensures that the engine remains
as uncomplicated and uncluttered as possible. Using ambient air-flow combined with engine
oil to keep engine temperature at an optimal level means that a radiator, fan, hoses, and other
components are unnecessary. This keeps the motor beautifully clean and essentially pure, like
the experience it provides.

Just as relevant as the engine’s individuality, is its sound. The characteristic ‘thump’ of Royal
Enfield’s singles is cherished by legions of enthusiasts, and great lengths were taken to ensure
that the new 650 twin gives an equally compelling soundtrack. Hours were spent tweaking
every contributing variable to engine sound, resulting in twin silencers that rumble with just
the right tone.

The entire platform, including the engine and chassis have undergone rigorous testing during
the development program. It has been subjected to lab and bench tests, in addition to
being tested on proving grounds, race tracks and public roads.
Leading the field among Royal Enfield’s latest generation of motorcycles, the new 650 twin is
the proud result of several years’ work by teams around the globe. As the heart of an exciting
line of upcoming motorcycles, it promises the potential to invigorate and expand the mid-size
motorcycle segment; bringing Royal Enfield’s style of uniquely pure motorcycling both to
existing loyalists, and to a whole new set of enthusiasts.