This invention relates to an engine assembly for a motor cycle more particularly, though not exclusively, to an engine assembly for a four stroke motorcycle engine assembly.
In conventional engine assemblies for motor cycle side thrust which the piston receives from the inner surface of the cylinder bore is reduced in this mvention lowering the frictional resistance to the sliding motion of the piston, thus contributing to lower fuel consumption.
Another drawback with conventional engine assemblies for motor cycle is the dynamic instability, caused by the centre of gravity of the vehicle being not in position.
The invention proposed herein seeks to overcome the abovementioned shortcomings.
The engine assembly for a motor cycle according to this invention has a crank case; a cylinder block; and a cylinder head joined to the upper end of the cylinder head wherein the cylinder block axis is offset towards the front of the vehicle by 5mm to 10 mm tomove the centre of gravity of the vehicle towards the front thereof; the axis of Ae cylinder block is offset with respect to the axis of the crankshaft whereby the angle of inclination of the connecting rod during the power stroke is


reducing the side thrust received by the piston from the inner surface ofthe cylinder bore.
This invention will now be described with reference to the acompanying drawings which illustrate by way of example and not by way of limitation one of possible embodiments ofthe engine assembly for a motor cycle proposed herein.
The engine assembly has a crank case C, a cylinder block B and a cylmder head H joined to the upper end ofthe cylinder block B.
The axis A ofthe cylinder block B is offset towards the front F for the vehicle by 5mm to 10 mm to move the centre of gravity ofthe vehicle towards the said front, thereby increasing the load on the front wheel ofthe vehicle and generally improving the dynamic stability ofthe vehicle for better road holding.
The axis A ofthe cylinder block is also offset with respect to the axis ofthe crankshaft D whereby the angle of mclination of the connecting rod R during the power stroke, is reduced by +1° 07* to +4*^15' in order to reduce the side thrust received by the piston from the inner surface ofthe cylinder bore lowering the frictional resistance to the sliding motion ofthe piston in the bore and also contributing to lower fuel consumption.

The above mentioned features also provide abetter aesthetic qipearance for the motor cycle.
It will be appreciated that various other embodiments of this invention are possible without departing from the scope and ambit of this invention.

We Claim:
1. An engine assembly for a motor cycle having a crank case; a
cylinder block; and a cylinder head joined to the upper end of
the cylinder block wherein the cylinder block axis is offset
towards the front of the vehicle by 5mm to 10 mm to move the
centre of gravity of the vehicle towards the front of the vehicle ;
the axis of the cylinder block is offset with respect to the axis of
the crankshaft whereby the angle of inclination of the
connecting rod during the power stroke is reduced by
+2" to +4 ° thus reducing the side thrust received by
the piston from the inner surface of the cylinder bore.
2. An engine assembly for a motor cycle substantially as herein
described with reference to, and as illustrated in, the
accompanying drawings.