How much is "a bit" ? I've got the hiragana, the katakana, a few Kanji and all the korewa, sonowa etc grammar rules. Will it be enough to visit Tokyo? No. But the way it works is sometimes a stupid attempt at speaking will trigger the "poor ~~stupid~~ helpless tourist" reaction that gets you help, which you won't get if you don't make yourself "vulnerable" as people say today, but do the opposite: implicitly demand that others make themselves vulnerable to you.