This invention relates to a dual mode automotive drive system which facilitates the change in engine input parameters and reduction in load on engine for increased power output from vehicle whenever desired.

This invention therefore proposes two different engine operating modes combined in a single vehicle. In the default mode normal commuting is possible, In the power mode improved acceleration can be achieved. A manual switch is provided for operation by the rider for change over from default to power mode and vice versa as required by the driver. Thus optimum combination of fuel economy and power in a single engine is obtained

A dual mode automotive drive system for a motor vehicle having default mode and power mode operation, according to this invention, comprises an ignition timing unit, electronic solenoid for the carburettor and a magneto assembly, the said ignition timing unit being provided with a set of ignition curves, wherein one is for default operation and the other(s) curve(s) for power mode operation; a carburettor provided with an electronic solenoid for supplying enriched fuel air mixture in the default mode operation for cold start of the engine, and for supplying enriched fuel air mixture continuously in the power mode operation; a magneto assembly for generating electricity to support load requirements of the said vehicle during default mode operation, the said magneto assembly being disconnected from the non-essential load during power mode operation; and a manual control switch connected to the said components, said switch, in its non-activated state, retaining the said system in its default mode operation, but in its activated state, causing the said components to change over from default mode operation to power mode operation

This invention will now be described with reference to the single figure (Fig.1) in the accompanying drawings which illustrate, by way of example, and not by way of limitation, one of possible embodiments of the drive system proposed herein.

The vehicle Is provided with a control switch S to change over from default commuting mode to power commuting mode and vice versa. Activation of the switch causes changes in operation of the ignition timing unit U, the electronic solenoid T of the carburettor C and the magneto assembly M, and vice versa in the non-activated state of the switch, as described in further detail below:

The ignition timing unit U is provided with two or more sets of ignition curves, wherein one relates to the default mode and the others relate to the power mode. The said default mode further has two curves one of which is for normal economy mode (curve 1) the other one is for default acceleration mode (curve 2). Activation of power switch causes ignition timing change over from default mode curve to a selected power mode curve.

The carburettor C is provided with an electronic solenoid T which in default mode, works only during cold start of engine, While working, in default mode, in the manner where it enriches fuel air mixture and helps in easy starting of the engine even in very cold conditions. Further, the activation of the switch causes the electronic solenoid to change over from default mode to operate continuously and provides rich air fuel mixture in power mode.

The magneto assembly M generates electricity to support the load requirements, such as, charging of the battery of the vehicle, power supply to the horn and lights or lamps among other among other requirements, in the default mode. It also provides a signal to the ignition timing unit in the default mode. However, activation of the switch S, causes disconnection of the battery charging and other non-essential loads from the magneto assembly M and thus reduces load on the engine.

In this condition, the essential load parameters for commuting remains unaffected.

Changes brought about from default mode to power mode take place simultaneously in all the aforementioned components, on activation of the switch S to cause ignition timing advance, rich air fuel mixture along with reduction in engine load. Accordingly, the power output of engine increases in power mode compared to default mode, which increases vehicle tractive force and vehicle acceleration

It will be appreciated that various other embodiments of this invention are possible without departing from the scope and ambit thereof.

We Claim:

1. A dual mode automotive drive system for a motor vehicle having default mode and power mode operation, comprising an ignition timing unit, electronic solenoid for the carburettor and a magneto assembly, the said ignition timing unit being provided with a set of ignition curves, wherein one is for default operation and the other(s) curve(s) is for power mode operation; a carburettor provided with an electronic solenoid for supplying enriched fuel air mixture in the default mode operation for cold start of the engine, and for supplying enriched fuel air mixture continuously in the power mode operation; a magneto assembly for generating electricity to support load requirements of the said vehicle during default mode operation, the said magneto assembly being disconnected from the non-essential load during power mode operation; and a manual control switch connected to the said components, said switch, in its non-activated state, retaining the said system in its default mode operation, but in its activated state, causing the said components to change over from default mode operation to power mode operation

2. A dual mode drive system for a motor vehicle substantially as herein described and illustrated with reference to the accompanying drawings.