Sounds like the castor is now less. Stock, there was just enough and you may have put it over the edge with the new parts.

Especially if you fitted new rubber on the tension rods, it will have changed the castor.

Have it aligned for 2.5 degree castor Alignment. It's non-adjustable, but they can cut the rubber down which will pull the castor rods forward a little. This will change the toe-in, so it needs to be readjusted too.