clean your tire with soap and water with an old toothbrush, let em air dry. then apply your decals on, then brush on microsol and leave them, you might apply the microsol a few times to really get the decals on good. then you can hit it with dullcoat lacquer.
you can spray tamiya or duplicolor lacquer gloss first if you want. but its not necessary
just make sure any clears you use are lacquer because enamels will never dry on the rubber.
James-interesting fact about enamels not drying on the rubber-do acrylics dry on rubber? Guess I could go get a tire from a kit and try it, but if you know…
I forgot to mention it is best to put the finished rims in the tires first before decaling the tires. Just find a dime or some coin the right diameter that you can place over them when you spray on the dullcoat , cause if your rims are difficult to put in the tire, it can damage your newly placed on decals!
I’ve been building a lot of 1/20 Tamiya F1 cars. Here’s what I do.
Paint the wheel rim and fit the tyre to it.
Mask the wheel rim with a coin.
Brush paint Future onto the side walls
Apply the decals as per the instructions.
Brush paint Future onto the side walls again. This will seal it and remove any air pockets that cause it to ‘silver’.
Spray acrylic flat varnish over the sidewalls until the desired flat finish is obtained. I find it helpful to add a minute amount of black acrylic to the flat varnish. it helps to tone down the whiteness of the decals a little. The way I do this is to dip the stirrer in the black prior to stirring the varnish.
Using this method, I’ve never had a problem with cracks appearing. However, it will crack if you try to fit the tyre onto a wheel rim after the process is finish. I think its due to the flexing of the rubber.