-Two type Direct injection or Indirect injection .
-The fuel injector is electromechanical system controlling amount of fuel injected by a term called PULSE WIDTH (Metering the fuel )
-The working principle is similar to a syringe
-The fuel injector allows control of fuel stratification and multi jets.
-Fuel injectors can be operated by Piezoelectric crystals or Using solenoids
-fuel and air are mixed by creating turbulence inside the cylinder
-most bikes use direct injection , at this case only air enters the cylinder during intake stroke and fuel is sprayed when the inlet valves begin to close
- Hence carburetor are pure mechanical systems ,and fuel injectors are controlled by ECU units
Advanced systems in engine
- Digitized fuel injection and controlled spark plugs have given excellent control of combustion process. This method gives good power with optimum fuel efficiency.APDV (Advanced Pro Series Digital Variable Ignition System)
- These systems use cam position sensor , crank position sensor for calculating the timing for fuel injection and spark.
- Other system includes creating turbulence inside the cylinder . Turbulence can be created inside the cylinder by altering the direction of air intake , direction of fuel intake,designing suitable piston head like shown below .
- Such systems are called as ASFS (advanced Swirl flow induction system),ATFT (advanced tumble flow induction technology)
- To Creating Swirl is something how the water spins inside a washing machine ,and Tumbling you might be aware of the rhymes Jack and jill where the kids might be tumbling down . Thats science 🙂
- Using more than one spark plugs, allows more heat to be supplied to engine.
- Some engines have More than one valves ie Two intake valves and two Exhaust valves. This is done to increase volumetric efficiency of engine. Simply saying it admits more charge inside the cylinder
- DTS -si(digital twin spark Swirl flow induction)
- Twin cam or Dual over head cams , this system allow to use two independent cams, separate cam for Intake and exhaust valves. (this just increases precision timing of valves, imagine when these engines are running at 1000-10000 rpm ,every milli second counts :P)
- CVTi used by TVS ( not to confuse with CVT transmission)
TVS Motor’s CVTi technology is a design innovation optimizes the air-fuel mixture in the cylinder with a unique combination of swirl and tumble motion. This generates a very high in-cylinder charge motion which in turn facilitates superior pickup, resulting in improved performance without negatively impacting mileage.
Electronics and electrical take 10-15 % of the parts in a modern motorcycle. These help the mechanical components work in a better way.