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Delhi Nixes Two-Stroke Three-Wheelers; Conversion to Four-Stroke Mandatory

Hindustan Times. The Delhi Cabinet is mandating that all two-stroke three wheelers—regardless of fuel—convert to four stroke engines in an effort to reduce pollution in the city.

The government will provider a Rs 6000 (US$128) subsidy to three-wheelers that had already converted from diesel to CNG to change to four stroke. There are some 55,000 three-wheelers running on CNG in the capital, of which around 15,000 are two-stroke vehicles.

The total cost of conversion to four-stroke engines is estimated to be around Rs 15,000 (US$322) and manufacturers have agreed to give a six percent concession to the owners of three-wheelers.


Rafael Seidl

In a crowded, sunny city like Delhi, four-stroke engines with three-way catalysts are indeed sensible. The old two-strokes produce about 30x the HC emissions, leading to various population health problems.

What I don't understand is this sentence: "three-wheelers [...] had already converted from diesel to CNG to change to four stroke"

To get from a two-stroke to a four-stroke, you need a new engine, not a new fuel (though you can change that at the same time, if you wish). Perhaps it's just a sloppy shorthand formulation.


Read it again: Diesel 2-stroke motors converted to run as CNG 2 stroke motors will get a subsidy to put in a 4-stroke motor.

allen Z

They want cleaner air in the city. I think New Delhi will do something similar due to the upcoming Commonwealth Games in 2010.



i know that I am on record as a pro DI 2 Stroke (counter to general wisdom). But i can tell you that this is the application when DI 2 Stroke eventually with cats(on both gasoline and CNG) are winners.

I have seen the conversions and know what the numbers are. 4 stoke is simply not the best technology here.



mikey- can you show a 2-stroke that is as clean as a gasoline 4-stroke (using any combination of catalysts and exhaust treatments) while still coming in at a better price than replacing what they have with 4-strokes?

tom deplume

Check out some of the Evinrude outboards.


We're not talking DI 2 stroke on these cheap motors. They have carbs, and they're dirty. DI raises the cost way beyond that of a 4 stroke. Look at Evinrude's prices!



"In May 2004, Orbital entered into licensing arrangements with Bajaj Auto
Limited, one of India's largest producers of two and three wheeler vehicles. The agreement provides for Orbital's fuel injection technology to be applied to a significant volume of Bajaj's autorickshaw three wheeler vehicles. These vehicles represent a growth market within India and are used for commercial purposes. The use of Orbital's technology will provide significantly increased fuel economy and reduced operating costs."

this much delayed OCP-DI 3-wheeler is slated for release before the end of Y2006.

wonder how this will change the minds of the Indian politicians....


have a look at "The EnviroFit Two-Stroke Retrofit Kit":


Hanif Muhammad

I need names of manufacturers of 4 stroke CNG engines for Vespa/Bajaj/Piaggio rikshaws. Can anybody guide me?

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