Steps for Calculating Compression Engine 4 stroke

Now we proceed to calculate the compression of a motorcycle. usually of a newmotorcycle brochure is listed how the compression of the motor. for example, motoryamaha jupiter has 1:9.4 compression. how to find it. formula as follows:

VC + VB
VB

VC = volume of cylinder
VB = volume of the combustion chamber

Jupiter has a cylindrical sample volume of 115cc.
and has a volume of the combustion chamber 13.85cc obtained by using a tool to fill the combustion chamber with a liquid that is jupiter burette can also use injectiondoctors who have cc size. see picture:


images that are colored blue are the combustion chamber to be filled with liquidusing a burette or a syringe inserted through the spark plug hole. when measuredusing the results obtained 13.85 cc burette. when calculated:

115 + 13.85
13.85
= 9.333333

Means the capacity of the engine compression standard Jupiter is 1: 9.3

nb: this formula is needed to How to modify a standard machine to machine racing

may be useful.