AVL’ s CCBR technology was applied e.g. to a 90 cc single - cylinder engine which was installed in a vehicle equipped with a single - speed automatic transmission with centrifugal clutch. The original 2 valve cylinder head of the air - cooled engine was replaced by a new air - cooled 3 valve cylinder head with CCBR intake ports and twin spark ignition.
The major target during the development was to achieve an excellent fuel consumption. The achieved results in terms of fuel consumption at constant vehicle speed are shown in picture 'Fuel economy at constant vehicle speed of a 90 cc single - cylinder engine'.
In the Indian Driving Cycle (IDC) a cruising range of 76 km/l was achieved.
Although the carburettor setting was optimised in the face of low fuel consumption it was possible to achieve the emission levels which indicate that it shall be possible to comply with Euro III emission legislation (of 2006) without fuel injection and three - way catalyst (TWC) under consideration of the following boundary conditions.