Why Holes Drilled In Wheels? 11" Wide Magnesium Wheels

I know about bead locks drilled on the edge of the wheel to keep the tire from spinning on the wheel. I have small holes, about 1/8", drilled in from the wheel edge more toward the mounting surface. If you divide the wheel in half I have 4 equally spaced on each side. They don't go all the way through and are threaded. Does anybody know the reason for these? Adding balancing weights? You can see them in the right wheel in the picture.

Click on the picture a couple of time for a real close up shot.

 

I believe the holes are primitive wheel locks. At the start of cars running flat tires for better traction some racers drilled small holes to run screws into the tire bead to prevent the tires from rotating on the rim.

 

Still common practice.

 

I added some better pictures. The holes don't go all the way through and they are threaded. Is it for adding weights for balancing?

 

Whats with the screws on the inside of the spokes?

 

Balancing, that's what I was told. Second pair of magnesium wheels I've had like these that had the screws with what looks like lead around it.

 

screw on balanacing weights. keep from flying off or quick replacement/ adjustment

 

they are for balancing , also the screws in your back side of spokes are for balancing , looks like there is still some lead in there

 

Sounds like a wheel weight attachment point, back in the 1930's Rolls Royce used a setup like that. Bob