Yamaha’s DiASiL Cylinder Vs Normal Cylinders – in Simple Terms

We also list Diasil cylinder advantages over the other conventional cylinders widely used in motorcycles – everything in simple, easy to understand terms…

Many of us have heard about the DiASiL cylinder but not all of you would be aware of its advantages over conventional cylinders. DiSAiL is abbreviated form of Die Cast Aluminum Silicon. This cylinder was invented by Yamaha. Its application can be found on Yamaha R series bikes.

Diasil cylinder advantages

Before we brief about DiASiL cylinder, let’s know the types of conventional cylinders. Cylinder is that part of the engine inside which the piston moves.

There are two types of conventional cylinders

1. Cast Steel Liner Aluminum Cylinder

These cylinders made of inherently soft aluminum have a cylindrical cast steel linear inserted along the inner wall of the cylinder to reduce friction resulting from the piston’s movement.


  • These cylinders are very reliable from the view point of reduced friction and reduce the possibility of engine seizure.
  • These kind of cylinders cost less.
  • They are easy to handle and replace.
  • Most of the motorcycles are manufactured with this kind of cylinder.


  • The heat transfer rate of this cylinder is reduced due to presence of cast steel liner (remember that the heat transfer rate of steel is 1/3 that of aluminum).
  • Manufacturing method inserting cast steel liner sleeves is very complex.
  • Poor recyclability
  • Manufacturing efficiency is low.
  • It is less environment friendly.

2. Plated Cylinder

The cast steel liner with a layer of metal plating on the cylinder wall is known as plated cylinder. There are many types of platings like chrome plating, NiKaSil (Nickle-Silicon-Carbide) plating, etc.

Diasil cylinder advantages


  • It weighs lesser as compared to the cast steel liner sleeve cylinder
  • It has slightly better rate of heat transfer
  • It is more reliable from the view point of friction as compared to cast steel liner sleeve cylinder.
  • Better reliability compares to cast steel liner sleeve cylinder.


  • Higher production cost.
  • Replacement is relatively difficult

DiASiL (Die Cast Aluminum Silicon) Cylinder

Diasil cylinder advantages

Now these conventional cylinders have respective problems like cast steel sleeve linear cylinder has problem of heat transfer and plated cylinder has problem of high cost. There was intense requirement of next generation cylinder which can overcome both the problems.

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In the year 2002, Yamaha invented DiASil cylinders which have overcame both these issues. It is made of 20% silicon content alloy. Yamaha DiASil Cylinder is a technology that brings together an ideal combination of material, manufacturing, technology and environmental friendliness.

Previously it was very difficult to produce such material but Yamaha has invented CF Aluminum Die-Cast Technology. It is the process in which the degree of vacuum in the die, the temperature of the die and the speed with which the molten aluminum injected into the die are precisely controlled in order to produce cast metal that has a highly abrasion resistant crystallization character with an even distribution of hard silicon particles. This makes it possible to mass-produce high quality all aluminum die-cast cylinders without cast cavities.

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DiASil Cylinder Advantages

DiASil Cylinder has the following advantages over cast steel liner cylinders:

  • 60% better cooling performance is possible
  • 30% lower manufacturing cost is possible
  • Excellent recyclability
  • Enables 30% lighter weight
  • Easily Transferred to overseas manufacturing bases
  • Rlatively more environment friendly

– Mahavir Kothari