Would you try to introduce a speaker who was about to walk onto the stage if you did not know who the speaker was going to be? I think the thesis statement is an introduction of the essays main idea, and you cannot know the main idea until you have written a few paragraphs about the articles you read.
Do not make a thesis statement and then try to find articles to support it. Read articles and write about interesting stuff you learn. Then, wait until a main idea takes form. When it does, write about it in the thesis statement.
Motorcycle helmets should be mandatory for all riders.
This might be too simplistic. To make your essay unique, do this:
Motorcycle helmets should be mandatory for all riders, because ____________(fill in the blank with an observation that some people might never have considered. You'll find great observations in the articles you read.)
:-)