[LesJ]

I guess I screwed up on the river here. My two opponents had been weakly betting prior to the river, so I thought a check-raise was in order. I guess they figured I was chasing a flush and decided to check down. How much should I have bet on the river?
PokerStars Game #2922112238: Tournament #14165400, Hold'em No Limit - Level IV (50/100) - 2005/10/29 - 13:48:41 (ET)
Table '14165400 118' Seat #7 is the button
Seat 1: Uproar2099 (6787 in chips) is sitting out
Seat 2: piggjigg (3785 in chips)
Seat 3: Brun5338 (8630 in chips)
Seat 4: twomanytat2s (9275 in chips)
Seat 5: jlm224 (6140 in chips)
Seat 6: chaseee (11092 in chips)
Seat 7: goombahjoe (8953 in chips)
Seat 8: saintspw (3350 in chips)
Seat 9: LesJ (8395 in chips)
saintspw: posts small blind 50
LesJ: posts big blind 100
*** HOLE CARDS ***
Dealt to LesJ [Kc Qc]
Uproar2099: folds
piggjigg: folds
Brun5338: folds
twomanytat2s: raises 300 to 400
jlm224: folds
Brun5338 said, "ok"
chaseee: folds
goombahjoe: calls 400
saintspw: folds
LesJ: calls 300
*** FLOP *** [4c Ks Ad]
LesJ: checks
twomanytat2s: bets 400
goombahjoe: calls 400
LesJ: calls 400
*** TURN *** [4c Ks Ad] [Jc]
LesJ: checks
twomanytat2s: bets 400
goombahjoe: raises 400 to 800
LesJ: calls 800
twomanytat2s: calls 400
*** RIVER *** [4c Ks Ad Jc] [8c]
LesJ: checks
twomanytat2s: checks
goombahjoe: checks
*** SHOW DOWN ***
LesJ: shows [Kc Qc] (a flush, King high)
twomanytat2s: mucks hand
goombahjoe: mucks hand
LesJ collected 4850 from pot
*** SUMMARY ***
Total pot 4850 | Rake 0
Board [4c Ks Ad Jc 8c]
Seat 1: Uproar2099 folded before Flop (didn't bet)
Seat 2: piggjigg folded before Flop (didn't bet)
Seat 3: Brun5338 folded before Flop (didn't bet)
Seat 4: twomanytat2s mucked [Th Ts]
Seat 5: jlm224 folded before Flop (didn't bet)
Seat 6: chaseee folded before Flop (didn't bet)
Seat 7: goombahjoe (button) mucked [Js Ac]
Seat 8: saintspw (small blind) folded before Flop
Seat 9: LesJ (big blind) showed [Kc Qc] and won (4850) with a flush, King high