Enter the bore size (in) and the stroke length (in) into the Calculator. The calculator will evaluate the Bore To Stroke Ratio. 

Bore To Stroke Ratio Formula

BTS = B / S


  • BTS is the Bore To Stroke Ratio (in/in)
  • B is the bore size (in)
  • S is the stroke length (in)

To calculate Bore To Stroke Ratio, divide the bore size by the stroke length.

How to Calculate Bore To Stroke Ratio?

The following steps outline how to calculate the Bore To Stroke Ratio.

  1. First, determine the bore size (in). 
  2. Next, determine the stroke length (in). 
  3. Next, gather the formula from above = BTS = B / S.
  4. Finally, calculate the Bore To Stroke Ratio.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

bore size (in) = 20

stroke length (in) = 10