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You should still be raising with JJ even if you expect 6 to every flop.
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According to HEPFAP, the exception would be when you expect three or four to the flop if you raise but 6 if you call. Then you want to play for set value because JJ doesn't play well against precisely two or three opponents*. At least that's Sklansky and Malmuth's take. In low limits it rarely matters because people will merrily call two bets as easily as they call one.
Keep in mind that
JJ is about even money to flop either an overpair or a set, and both of those can be extremely profitable in a multiway pot. If your pot equity is well above 16%, but less than 50%, and you're guaranteed a 6-way pot regardless, you want that pot to be as big as possible so that your share can be as big as possible.
*I'm 90% sure it says "two or three opponents" but don't have it handy right now.