It is a popping resonating sound generated by a lean condition on deceleration. When you suddenly close the throttle, the incoming air is choked off and the closed throttle also causes the bike to return to idle on the very lean idle circuit.
The reactivity series of metals was deduced by performing several experiments in the lab which enabled scientists to arrange metals according to their reactivity with dilute acid, oxygen (air), and water.xides of iron and copper are insoluble. Metals that are less reactive than copper like silver, gold and platinum do not react with oxygen. Note: When aluminum reacts with oxygen, a layer of aluminum oxide adheres and covers the aluminum.
For example in the table above it should be appreciated that magnesium will react with copper oxide reducing it to copper metal. Any metal that is more reactive will react with compounds of less reactive metals. Reactivity series involving non-metals. Metals react by losing electrons-they are reducing agents.Non-metals react by gaining electrons-they are oxidising agents.In the same way that metals can be ordered in terms of reducing strength, the non-metals can be ordered in terms of their oxidising strength.eactivity series involving non-metals. Metals react by losing electrons-they are reducing agents. Non-metals react by gaining electrons-they are oxidising agents. In the same way that metals can be ordered in terms of reducing strength, the non-metals can be ordered in terms of their oxidising strength.