How much would you bet here?

[pukenpete]

UB 5.50 sng, blinds 20/40

Puken Pete (SB) is at seat 0 with 1245.
BB is at seat 1 with 1575.
UTG is at seat 2 with 2470.
UTG+1 is at seat 5 with 2155.
CO is at seat 6 with 1175.
Button is at seat 8 with 1380.

Puken Pete: Kc 9c

Pre-flop:

UTG folds. UTG+1 folds. CO folds.
Button folds. Puken Pete calls. BB checks.

Flop (board: Qs Td Kd):

Puken Pete bets 80. BB calls.

Turn (board: Qs Td Kd 7h):

Puken Pete bets 240. BB calls.

River (board: Qs Td Kd 7h 4d):

BB had only shown down 2 hands, both of which were monsters. However, I'd also noticed twice before that it looked like he was drawing and when the river hit blank, he'd quickly fold to a bet. This led me to put him on a draw but when the 3rd diamond hit, I didn't want to check since it basically screamed for him to bet me off. So what would be the right amount to bet to show that I'm not weak yet not overcommit myself?

[SixgunSam]

That is a tough call, I hate situations like this. That is why I don't defend the SB very often early in a tournament. You are already into the hand for 1/4 of your stack at the turn. From what I would guess by his calling, he is probably on some kind of a draw or has a very marginal hand ( like you do ) and wants to show it down. If it were me, I simply check the turn and keep the pot small. This started out as a really small pot and I would be content to win a small one or lose a small one. It's hard to get away after you have committed so many chips. Playing out of position with a hand like yours, you have to have a great read, but I think the root of your dilemma is that you have overplayed your hand at the turn. This is a difficult situation and I would be curious to how some of the experts here would answer it.

[betgo]

I would check the river, and call a reasonable sized bet. If he goes allin, I would probably fold.

Preflop, I would raise to 100 or 120. You have a better than average hand. Pick up the blinds or raise the stakes.