These are currently some of my favourite wheels. En Route WedsSport SA-55M
Available in only black or white, 6mm or 9mm they need a bit of TLC.
First I usually machine the support rings off on the lathe. While you can use O-rings with the support rings in place, I find it easier to mount tyres with the flat surface.
If I use paint. I always apply numerous coats of hard enamel.
The result with tyre is 28g.
The other day I tested the heavier alloy rims which I found to be quite good. So I decided to use this flexible weak magnetic material with adhesive backing as a weight.
The result is a 7 gram gain. not too much, After I check clearance I may add another layer for a 14g gain.
By the way. If you want to add weights to your body or chassis. Instead of buying Kazama, Wrap Up Next or other brands, Just go yo your local tyre dealer and get some of these adhesive lead weights for Apply Wheel application. Usually they will give them to you free of charge.
If you spend a bit more you can get the carbon print versions etc.
They are all separate, in 5g and 10g sections. Just cut the backing tape where desired and apply.
Have fun with weight tuning.