FYI There are websites and services that cache websites FOREVER. Wayback machine is one example. The NSA probably has also does this, etc. You can scrub it from google but just you let you know, forum postings are basically quasi-permanent.
This is why I do not (and most people don't) give their real names on a forum. It's also possible, to a ridiculous and shocking degree, to aggregate information you leak piece by piece on internet forums until someone has an extremely detailed picture of your life and interests, etc, phone number, tenure at work, education, spouse, address, kids, car...