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|Calculating Engine Displacement|
How to Determine the Displacement of a Kart Engine
Here’s what you will need.
Step 1 Remove the cylinder head from the engine.
The engine should not need to be removed from the kart to do this although the
Step 2 Position piston at bottom dead center (BDC)
To accomplish this use insert the 5/16 hex key in the starter nut or place a socket on the clutch nut. Turn the hex key or socket wrench until the piston is all of the way down to the bottom of the cylinder. Another way to get the piston to bdc is to simply push the piston down with your finger.
Step 3 Measure and record the cylinder bore.
Use the digital or dial caliper to carefully measure the cylinder bore. Be very
A. Make sure that the piston is pushed all of the way down to the very bottom of the cylinder.
C. Insert the dial indicator into the hole in the bridge just enough for it
D. Turn the face of the dial indicator so that the needle is pointing to zero.
E. Slowly turn the crankshaft with one of the wrenches while watching the dial.
F. Count how many full times the needle revolves plus how many additional
G. Record the reading. This measurement is the stroke of the engine.
Step 5 Calculate the Displacement of the Engine
A. Plug your measurements into the following formula.
____________ X ___________ X _____________ X .7854 = Displacement
B. If the measurements were made using the metric system, in other words, in millimeters, the result will be the cubic centimeters of the engine. You now know what you need to know to calculate the entrant’s minimum weight.
C. If the measurements were made using the customary system, in other words, in inches, the result will be in cubic inches. This willneed to be converted to cubic centimeters.
D. To convert cubic inches to cubic centimeters;
__________ X 16.39 = _________ CC
Questions or comments about these instructions should be directed to;