Stars $50 50K...turn set in multiway pot...ugly river...line check

[ssnyc]

taking a shot at the $50 MTT...please comment on my line...

preflop bet okay or too small? (7 people calling 7X OMG!)
flop check in 7 way pot?
turn raise a good size? (love the $80 lead into $860 pot)
check call river an okay line?

I though players would be a little better at $50 but wow!!??

Poker Stars
No Limit Holdem Tournament
Blinds: t10/t20
9 players

Stack sizes:
UTG: t520
UTG+1: t3410
MP1: t4800
MP2: t4140
MP3: t2970
Hero: t2950
Button: t2050
SB: t3200
BB: t2930

Pre-flop: (9 players) Hero is CO with J[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/spade.gif[/img]
UTG calls t20
UTG+1 calls t20
MP1 calls t20
2 folds
Hero raises to t140
Button calls t140
SB calls t130
BB folds
UTG calls t120
UTG+1 calls t120
MP1 calls t120

Flop: (t860) 4[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/club.gif[/img] 7[img]/images/graemlins/diamond.gif[/img] (6 players)
SB checks
UTG checks
UTG+1 checks
MP1 checks
Hero checks
Button checks.

Turn: (t860) J[img]/images/graemlins/club.gif[/img] (6 players)
SB bets t80
UTG folds
UTG+1 calls t80
MP1 calls t80
Hero raises to t500
Button calls t500
3 folds

River: (t2100) 8[img]/images/graemlins/club.gif[/img] (2 players)
Hero checks
Button bets t820
Hero calls t820

Final pot: t3740