In the examples file the longest japanese and english 'A' texts are 127 and 253 characters respectively.
There's a bit of an ulterior motive behind that "253" number. The 建前 is that this is a collection of example _sentences_ not example novels. A few really long entries and entries of multiple sentences have been split up. The 本音 is that if I add a sentence with more than 255 characters I'll have to use a memo field instead of a text field for the English, and I don't particularly want to do that.