Why diesel engine is not used in bikes?

We use bike many times in a day. Usually bike is run on petrol. The price of petrol is higher than diesel in many countries. Sometimes we think, why bike is not run by diesel. If there is a diesel bike than we can save some money. Actually,we do have diesel engines for two wheelers, but not in the scale the petrol engines are. There is only one type of bike with a diesel engine in India and that is the Royal Enfield Taurus.This is shown in figure below :-

The main reasons for not using diesel engines in two-wheelers are as follows:

1. Diesel engine has a compression ratio 24:1, which is higher than petrol engine compression ratio of 11:1. Diesel engine must be bigger and of heavy metal in order to handle this high compression ratio. That's why the diesel engine is heavier than petrol engine and not suitable for small vehicle like motorcycle.

2. Due to high compression ratio, diesel engine produces more vibration and noise as compared to the petrol engine. It is not possible for a light vehicle to handle this high vibration and noise.That's why diesel engines are not used in motorcycle.

3. Due to high compression ratio and heavy engine, initial price of the diesel engine is more than the petrol engine. And this initial price difference is about 50,000 rupees, which is not suitable for small vehicle.

4. Diesel engine produces approximately 13% more carbon-di-oxide per gallon as compared to the petrol engine. So it makes greater pollution than petrol engine and it is not good to use for environment.

5. Diesel engine works on high pressure, so wear and tear is high in diesel engines. To reduce this wear and tear oil change are frequently required at every 5,000 kilometer instead of 10,000 kilometer in the case of petrol engine.

6. Diesel engine produces more torque but low rpm than petrol engine. So in bikes where we need high speed, it is not suitable.

7. Diesel has high energy per gallon as  compare with the petrol. When diesel burns, it produces a large amount of heat which can destroy walls of the cylinder and other parts of the engine. So to reduce this heat, we need a greater surface area and proper cooling system. In order to achieve this greater surface area, the engines are made slightly bigger.

8. Diesel engine uses turbocharger or supercharger to pump more air into the cylinder, which increases its price and size. 

9. In diesel engines, injector technology is used to inject fuel into the combustion chamber, which is more expensive than spark plug technology of petrol engine.

10. Diesel engine is very big as compared with the petrol engine and it uses high power starting motor to crank the engine, which is not suitable for motorcycles.


  1. I'm no expert myself. But, this looks as if some undergraduate student, who is just trying to fill the pages in his examination, wrote this.
    The point "diesel engine is 'Big'" is twisted and repeated a lot.
    I would expect better points and explanation of such a simple topic.

    1. Something is always better than nothing dude, so let's appreciate him.
      Thanks for reading this.

  2. Good information and it's use full .

  3. Replies
    1. information is information dude university type or as a pro

  4. Thakq for providing such type of useful information

  5. Information is correct,, acceptable,,

  6. Never heard such a load of rubbish in my life....big?...explain why there is engines available for remote control aircraft then!. Can't agree with one point on this.

  7. First of all, someone is Putting his or her efforts to think differently itself is very important. Good to know basic information of difference in 2 engines. Keep it up