There are a few strange aspects of motorcycle tires (sport bike tires specifically). First off, they curve on two different axes simultaneously. Secondly, they usually have intricate tread patterns that seem to have been carved by a tattoo artist; modeling the treads on them is tricky to say the least.
The best approach I’ve found is to not model the treads. Traditionally I’ve used normal mapping or simply bump mapping along with a slight variance in the color map. This weekend I decided to give it another shot: I created an intricate tread pattern (loosely based on the Dunlop Elite series) and with careful use of deformers and more specifically deformation/subdivision order I was able to create what I think is my best attempt at the aforementioned subject matter yet!
Let me know what you think; the images are with and without subdivision.