I just finished building some wheels. Mounted tires, put them on the bike, rode around the block. The first two or three feet of rolling, the spokes made several pinging or tinking sounds. Then no more sounds.
Is it pretty much inevitable to hear pinging from the spokes when first riding a new set of wheels? Or is it a sign that I did not build the wheel properly?
These were Mavic Open Pros on Mavic 500 hubs, butted DT Swiss spokes, I thought I took a lot of care building them. But what do I know.
As others have said, spoke windup is responsible for the pings. As the spoke nipple gets tighter it can cause the spoke to turn. If you hold the spoke while you tension, you can feel the spoke twist in your fingers and can relieve it during tensioning by turning back slightly if you feel the spoke twist. The backward turn is going to be very small rotation. A 1/16 of a turn would be huge. Placing a drop of light oil between the spoke and the rim also helps.
Personally, I don't do the 'push down on the rim' thing and haven't for 25+ years of wheel building. By monitoring the twist, adjusting it during tension and lubricating the rim/spoke interface, I make wheels that don't ever ping when I ride them.