Follow up on this turn?

[cmwck]

BB is new to the table, and it looks like MP is shaping up to be extremely loose: 85% vpip after 17 hands

PokerStars 2/4 Hold'em (5 handed) converter

Preflop: Hero is UTG with 7[img]/images/graemlins/club.gif[/img], 7[img]/images/graemlins/heart.gif[/img].
<font color="#CC3333">Hero raises</font>, MP calls, <font color="#666666">2 folds</font>, BB calls.

Flop: (6.50 SB) 8[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, <font color="#CC3333">Hero bets</font>, MP calls, BB calls.

Turn: (4.75 BB) J[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, Hero bets....?


I bet because a typical player (and MP esp.) would call the flop with an overcard or two or a flush draw, and the turn card is probably no help to them.

And, just for fun, what's the maximum number of overcards (and their rank) that have to appear on the flop in this situation before you won't bet the flop anymore?