Degrees to MM Timing calculator

This is useful if you are building an engine and have a dial gauge. hand tighten the barrel down with the head off, then set the dial gauge up so it is at zero when the piston is at top dead center (TDC).
Enter the timing in degrees that you require into the calculator below and it will tell you how many millimeters the piston needs to travel before TDC, you then turn the flywheel anticlockwise until the dial gauge reads that number. You can then mark the Mag housing at the position of the arrow on the flywheel to mark your desired degrees.
I always use this method as its very accurate, also if you are using an advance retard ignition system you can mark several different timing marks on the Mag which you can then use to check the timing with a timing gun.
See the image below

Ignition Timing in mm Before TDC Calculator

Timing Degress A:
Conrod Length:  mm
Stroke:  mm
mm before TDC:  mm