I have a set of weld draglite wheels that I’d like to use for this season. My problem is with balancing the wheel. The technician had a very hard time trying to balance, but because of the moving centre part the values are different for every run. I’m thinking of getting some M12 x 1.5 bolts and fix them along with the lugnuts to prevent the movement, but wouldn’t removing them again cause slight movement and a shift in balance.

 

The center insert is very close to the axis of rotation, and isn't going to have a large affect on the balance if it moves slightly. My approach was to simply insert the shanked lugs to hold the insert in place, and do a static balance. Should be adequate. As long as you have the shanked lugs in there, the center insert will be in the same position it will be held in with the lugs installed on the car.