When the paint becomes scratched on your motorcycle's gas tank, it can cause the bike to look old and neglected. Leaving the scratched paint can lead to other problems, too, including rust. If the scratches are light, you can repair them easily with just a few materials. If the gas tank has a deep scratch, then it will need to be repainted or replaced. There are two different methods you can employ to repair scratches in gas tanks.
Wash the outside of the gas tank. Gently remove the dirt, dust and other debris with warm, soapy water and a soft sponge. Dry the area thoroughly with a soft cloth.
Apply some fine-cut abrasive polish to a soft cloth. Begin polishing the entire gas tank. Move the cloth in a circular motion and add more polish as necessary. When your cloth starts looking dirty, change to a clean one.
Leave the polish to dry according to manufacturer's directions, because each brand of polish is different.
Buff the polish away with a clean soft cloth when the recommended time has elapsed.
Apply a swirl remover with a soft towel. Rub it in onto the gas tank in a circular motion, then up and down, side to side and back to a circular motion. Follow the manufacturer's directions for the proper time to leave the remover on.
Buff with a clean, soft cloth. Repeat step 5 if necessary.
Clean the gas tank as directed in the first section.
Mix three drops of liquid detergent in a bowl of cold water. Soak a piece of 2000- to 3000-grit sandpaper that you have attached to a rubber sanding block in the bowl. Leave the sandpaper in the water for three minutes.
Remove the sandpaper and lightly sand the scratched area in short strokes. Don't sand too much or you will go through the top clear coat. If this happens, you will need more extensive repairs.
Find the colour of the gas tank and purchase either a paint pen or a small bottle of paint with a small brush. Apply a thin coat of the paint, following manufacturer's directions for drying time. You can add a second coat if needed. Allow it to dry for up to 24 hours.
Paint on a thin layer of clear top coat. This must be applied in one direction only or you will not create a smooth, professional looking finish. Allow it to dry for 24 hours.
Sand the area again as you did in steps 2 and 3. Wipe the area with a soft cloth; a haze will develop.
Buff the area with finishing compound applied to a clean cloth.