Multiple opportunities to raise

[Robb]

I know it seems like an elementary question but I had to pause during the hand. Don't know anything about PFR. 2nd and 3rd limpers are donaters.

Online 20-40:
First hand I post in the CO and am dealt A [img]/images/graemlins/spade.gif[/img]4 [img]/images/graemlins/spade.gif[/img]
3 limpers and I check. I don't like a raise here, some might. SB raises, BB and the rest call.

Flop: 3 [img]/images/graemlins/club.gif[/img]5 [img]/images/graemlins/diamond.gif[/img]7 [img]/images/graemlins/spade.gif[/img]
SB(PFR) bets BB drops limpers call. I call.
I contemplated raising but was afraid SB would re-raise and shut out the field. In this case though it probably means he has an overpair and not an ace so it may clean up my ace outs and it may clean up my chopping straight outs in a pretty big pot. Not to mention he may not raise and my raise has plain value. In addition I may get to check behind on the turn if I choose to. So in retrospect I think it was a mistake to not raise. Agree-disagree?

Turn: J [img]/images/graemlins/spade.gif[/img]
SB bets 1st limper drops the other two limpers call and I raise. I think another not so clear cut play because of my position and PFR has shown strength on 3 streets and is likely to have an overpair and re-raise. But I have equity with 4 players and if I don't raise and hit my draw on the river I will regret not raising because it will often go check check check to me and I only get 1 caller. Or if someone else hits the same straight they'll bet, I'll raise the others will drop and I will again have regretted not raising on the turn because I make no money on the river by chopping. Thoughts?

[JeffO]

I think you missed a clear value raise on the flop, and I don't like the turn raise.