interesting 3 way (dry sidepot) hand v. tay 25/50

[dlpnyc21]

This one was kind of a doozy. Advice on all streets welcome. Here I raise it up utg and get 3 callers, including Tay from the BB. He most likely views me as weak, as seen from an earlier hand I posted on this site. In any case. I'm not sure why I bet this flop, most likely stupidity, but I decided to anyway. I think the flop bet is a huge mistake into 3 people. Anyways, shortstack shoves, and here is where the hand gets interesting. Tay cold calls. I have an ez call here, but right now I was scared he was already nutted. After 2 callers he can come along from the BB with pretty much any two, including small pockets and suited connectors. I put his range on a 7 at bare minimum, maybe 68 (although I think you can heavily heavily discount this as part of his range). So his range is something like:

55, 77, 57s+, with 68 being a small small small possibility.
Turn brings my straight, but he checks. I decide I don't want to bet/call a cr shove, so I check behind. I was going to value bet river if checked to and evaluate river if he bet (most likely fold). River is a horrible card, flush comes out, higher straight comes out, he could already be nutted...sooooo...i decided to call because he bet so small?

Where did I go wrong in this hand. Thanks,
dlpnyc21


Full Tilt Poker
No Limit Holdem Ring game
Blinds: $25/$50
6 players
Converter

Stack sizes:
Hero: $5000
UTG+1: $9697
CO: $1183
Button: $11373
SB: $5147
BB: $1225

Pre-flop: (6 players) Hero is UTG with 4[img]/images/graemlins/diamond.gif[/img] 6[img]/images/graemlins/diamond.gif[/img]
<font color="#cc0000">Hero raises to $175</font>, UTG+1 calls, CO calls, Button folds, SB calls, BB folds.

Flop: 5[img]/images/graemlins/heart.gif[/img] 7[img]/images/graemlins/club.gif[/img] 7[img]/images/graemlins/diamond.gif[/img] ($750, 4 players)
SB checks, <font color="#cc0000">Hero bets $615</font>, UTG+1 folds, <font color="#cc0000">CO raises all-in $1008</font>, SB calls, Hero calls.

Turn: 3[img]/images/graemlins/heart.gif[/img] ($3774, 2 players + 1 all-in - Main pot: $3774)
SB checks, Hero checks.

River: 9[img]/images/graemlins/heart.gif[/img] ($3774, 2 players + 1 all-in - Main pot: $3774)
<font color="#cc0000">SB bets $1600</font>, Hero????