Originally Posted by rekmeyata

Depending on the model it may not be worth pouring money into it. Some light scratches can be buffed out using a rubbing compound, but you have to be careful because paint on bikes are really thin and you could buff too much damaging the paint and the decals, in fact don't even buff over the decals. Once you have the more serious scratches reduced, then use a non-abrasive scratch remover. Once you have that done, go over it with a ceramic spray on wax. It won't come out looking brand new, but it will look a lot better.

By the way, just use car products, don't buy expensive bike boutique waxes, that stuff is junk. Turtle wax makes the best consumer level buffing compound, Meguiar's Mirror Bright polishing wax to reduce the minor stuff after buffing, and lastly Jay Leno's Garage Radiant Ceramic Coating to make it really shine and protect the paint from UV.

The rubbing compound will take some elbow grease, the rest goes on easily, and of those last two products, the Meguiar's and the Jay Leno's, whatever you have left over, use it on other bikes, or do the cars!