Trying new things -- betting into a 4 flush w/ fold if raised strategy

[Mizzles]

I NEVER bet into a four flush on the board without one of that suit, so I tried it here.

Bet or check/call this river and why?

Party Poker 15/30 Hold'em (9 handed) converter

Preflop: Hero is BB with K[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/club.gif[/img].
<font color="#666666">2 folds</font>, MP1 calls, <font color="#666666">3 folds</font>, <font color="#CC3333">Button raises</font>, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero 3-bets</font>, MP1 folds, Button calls.

Flop: (7.66 SB) 8[img]/images/graemlins/spade.gif[/img], K[img]/images/graemlins/spade.gif[/img], 6[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

Turn: (4.83 BB) 5[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

River: (6.83 BB) J[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">Button raises</font>, Hero folds.

Final Pot: 9.83 BB