Piston Installed backwards?

[ILOAD2]

If the piston was installed backwards on the Yamaha 5 valve motor,would the 3 intake valve buckets depress fully and smoothly as I hand crank the motor via the 17mm nut on the rotor? Or would it lock as the center intake valve depressed?

[highmarker]

most likely hit the piston but never tried it, if your not sure pull it apart or maybe use a bore scope like used for checking wash on a twostroke to look through the plug hole.