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Updated: Oct 30, 2019

Everyone might have heard of the motorcycles powered by DTS-I and DTS-SI technology.

So ,what actually is DTS-I & DTS-Si ?

DTS-i stands for Digital twin spark ignition. The technology is currently used in Bajaj motorcycles in India because they have patent rights. Digital twin spark ignition technology powered engine has spark plugs at either sides of the combustion chamber. Engines powered by DTSI technology will have greater combustion rate because of twin spark plugs located around it. DTSI technology enables the engine to combust fuel at double rate than normal, this enhances both engine life and makes it fuel-efficient i.e. better as regards mileage.

The technology also results in smoother operation, adjusts the engine to varied temperature fluctuations and makes the motorbike resistant too breakdown. Overall, the bikes with the technology are supposed to live longer, run smoother with high fuel efficiency.

DTS-Si (Digital Twin Spark Swirl Ignition) on the other hand is an upgraded version of the present DTS-i technology developed by research and development team of Bajaj and they have patented it too. Under this technology, the digital twin spark plugs are located at same place like in DTSI technology engines but in an inclined or diagonal manner.

Placement of the spark plug in diagonal manner, helps in better mixing of the fuel-air mixture this led to improve the combustion and increase the efficiency of engine further.

Construction & Working of DTS-Si powered engines:-

DTS-Si stands for digital twin spark - swirl ignition, it is similar to DTS-i technology difference being the cylinder has grooves which causes turbulence of the air fuel mixture entering the cylinder making it 'swirl' hence better combustion takes place, giving better efficiency and power.


Twin Sparkplugs

Twin sparkplugs for faster and better combustion. Currently one spark plug at one end of the combustion chamber is the conventional practice. The flame front created by the spark takes some time to reach the farthest portion of the combustion chamber. This leads to slower burning of the Air-fuel mixture and creates limitations in optimizing the combustion chamber characteristics. 2 spark plugs at either ends of the combustion chamber help in faster and better combustion.

Ignition with a Digital C.D.I.

Capacitor Discharge Ignition

A Digital CDI with an 8 bit microprocessor chip handles the spark delivery. The programmed chip’s memory contains an optimum Ignition timing for any given engine rpm, thereby obtaining the best performance characteristics from the combustion chamber. Working together with the TRICSIII system, it delivers Optimum Ignition Timing for varying load conditions.


Throttle Responsive Ignition Control System IIIrd generation. It is a means of controlling the Ignition by operating the Throttle. Depending on the needs of the Rider whether it be cruising, acceleration or max speed, the ignition requirements constantly change. Based on a particular amount of Throttle opening, the Magnetic field generated by the Magnet opens or closes the Reed switch. The Reed switch is connected to the Digital CDI, which signals the CDI to change/switch, the desired Ignition Advance Timing Maps. This helps in achieving a good balance between drive ability and Optimum Ignition Spark advance, resulting in an almost perfect Ignition Spark advance for every Throttle opening and Engine rpm.

Constant Velocity (CV) Carburetor :

The CV carburetor continues to provide high level of performance.On conventional carburetors the throttle cable is connected directly to the throttle slide. However, as the throttle is opened on a CV-type carburetor, the air pressure difference between the outside atmosphere and inside the carburetor venturi forces the slide up and down. This type of system allows the carburetor to feed the engine a very precise amount of fuel/air mixture which increases fuel economy and gives good throttle response. The precision of the CV carburetor also helps meet emission regulations.

Chambers having low turbulence give rise to propagation of a flame front, which is akin to that of a gradually expanding balloon. This results in a slower rate of combustion and thus slower rate of pressure rise. The end result is lower efficiency. When high turbulence is generated and combustion takes place, the surface of the ballooning flame front fragments itself, with projection like fingers, and this increases its surface area, thereby improving combustion further.

How DTS-SI system is better than other technology?

Difference between Conventional & DTS-Si Induction

  • The twin spark plug:-

DTS-SI engines utilize Dual Spark ignition for faster and better combustion. Conventional 2-wheeler engines use one spark plug at one end of the combustion chamber. The disadvantage of the single spark engine is that the flame front takes some time to reach the farthest portion of the combustion chamber. This leads to slower burning of the Air-fuel mixture and creates limitations in optimizing the combustion chamber characteristics.

  • Swirl Ignition :-

Rotating flow (swirl and tumble) in premixed spark-ignition engines and its effects on turbulence generation and flame propagation. Rotating flow can significantly increase turbulence intensity during the combustion period. This in turn can lead to a reduced burning period and increased thermal efficiency. In general, rotating flow can substantially increase flame propagation speed, reduce cyclic variations, and expand the lean limit.

  • The engine becomes powerful and fuel-efficient.

  • The expected life of the motorcycle increases.

  • Bikes powered by the technologies are very well resistant to breakdowns and temperature fluctuations.

  • The throttle response is good because of the C.D.I & TRICS III.

  • DTS-Si (Digital Twin Spark-Swirl induction) technology. The engine with swirl induction is gives an amazing mileage of 70-80 km per litter under the road conditions.

By generating two sparks at either ends of the combustion chamber, (approximately 90° to the valve axis) the air-fuel mixture gets ignited in a way that creates two flame fronts and, therefore, a reduction in flame travel of the order of 40 per cent is achieved. A fast rate of combustion is achieved leading to faster rise in pressure. The obvious outcome of this is more torque, better fuel efficiency and lower emissions.


This sporty bike powered by a strong and high performing power train. It sports 4 stroke, DTS-I, air cooled engine. Maximum power and torque is increased in the 178.60cc bike. The DTS-SI engine develops maximum power of 17.05PS at 8500 rpm and churns maximum torque of 14.22 NM at 6000 rpm. The Digital Twin Spark ignition technology provides the engine to perform in much better way whether it is speed, acceleration or power. Contrary to the general one spark plug at the end of the combustion chamber, this bike comes with Bajaj patented DTS-I tech which have two spark plugs at both end of the combustion chamber.

For handling the spark delivery, a digital CDI chip is there. That gives optimum ignition time for load conditions. In addition to this, a Throttle Response Ignition System III (TRICS III) controls the ignition by operating the throttle.


Ø Less vibrations and noise

Ø  Long life of the engine parts such as piston rings and valve stem.

Ø  Decrease in the specific fuel consumption

Ø   No overheating

Ø   Gradual increases in the pressure hence power is uniformly distributed throughout the crank angle and hence smooth ride.


Ø The main disadvantage is the maintenance of the two spark plugs

Ø  Excessive cooling equipment required

Ø  Since high voltage sparks are continuously produced the heat due to sparking need to be cooled effectively

Ø  Cost increases due to additional technology.


             By inventing DTS-SI Technology Bajaj Company had stamped his better image in the Indian Two Wheeler Market.

             Due to this technology following implementation in engine were happened:-

Ø Less pollution is created.

Ø Due to complete combustion average of bike get raise.

Ø Noise & vibrations are minimized.

Ø Increase in life of engine & engine parts.

Ø Higher pickup is achieved.  

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