Six measurements in, piston spec out.

How to measure

With the barrels off and at room temperature, measure each bore at the top, middle, and bottom of ring travel — one reading along the crank axis and one across it at each height, six per cylinder. Enter all twelve on the left and hit Analyze: we'll grade taper and out-of-round against factory limits and tell you which piston to order. Not sure what the numbers should look like? Load the example readings and analyze those first.