Modern Vespa

Here is a PX flywheel next to the new SIP lighten one. You can see the timing marks are in different spots. However, when I look underneath, the spot that fires the pickup looks to be in the same position relative to the key way.

So on the front side, is the mark to help with the timing relative? Could I just paint a new white mark straight above the keyway like on the px flywheel? It seams logical tp me, or am I missing something?

This way it will generally line up with my TDC marks on my case and make it easier yl set the timing.

The timing locations are different for small and large frame. This flywheel can do either. You should not use any precast mark for timing. Make your own Tdc mark using a piston stop and a degree wheel. Make your own timing marks for your timing gun if it doesn’t have advance. The casting marks are notoriously inaccurate.

Mine factory marks were off by something like 6 degrees.

Yes, I always make my own timing marks on the case using a dummy plug. But what about 5he reference point on the flywheel.

Your reference point is the new mark you make on the flywheel so the timing light can pick it up. Make a new reference mark.

What crank do you plan on using? P style or Femsa Rally? If it’s a Femsa Rally crank, you can’t use either.