CO is 20/13/2 over 600 hands. River AFQ is 49%. UTG is your average loose passive fish.

Poker Stars $1/$2 Limit Hold'em - 5 players
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Pre Flop: (1.5 SB) Hero is SB with K A
UTG calls, CO raises, 1 fold, Hero 3-bets, 1 fold, UTG calls, CO caps!, Hero calls, UTG calls

Flop: (13 SB) 3 4 8 (3 players)
Hero checks, UTG checks, CO bets, Hero calls, UTG folds

Turn: (7.5 BB) 6 (2 players)
Hero checks, CO bets, Hero calls

River: (9.5 BB) Q (2 players)
Hero checks, CO bets, Hero calls

I thought long about check-raising the flop, but I didn't want to get three-bet. Hmm?

I figured my hand was pretty decent with two overcards and and a backdoor flush draw.

Hmm, I really don't think he has AJ+ here that often, I really think that Q rapes up. Our best cast scenario is when he also has AK. I think it's pretty close to a fold.

What range should we give CO and then I'll stove it.

This situation seems to come up a lot. I am glad you asked the question. I have been folding the river unless I have a good read on the opponent.

i would fold river in a heartbeat

I also fold the river. If a good card had fallen, like a board pair for example, I think you can call, but honestly I don't see how we're good enough to call the river. The guy did cap and bet every single street, and if he's FOS the queen is gonna have bailed him out like half the time.

I'm calling any T or lower on the river, folding any Q, probably folding a J but that would be tougher

So all you guys are folding 22 on the river as well?

I don't really think you should ever have 22 in this spot, maybe i'm a nit.

yes

when he c-bets that river it seems like you're in bad shape. You only rly chop with AK and AK probably doesn't bet. AJ probably isn't in his preflop range... nothing else makes sense and like every PP in his range has an easy value bet.

I think its ok to make a tight fold on the turn in general, but i don't think you can ever be good often enough on this river.

edit: regarding the flop check/raise, it is pretty big. you probably aren't making that big of a mistake by attempting to induce folds especailly if villain is capping like 99/TT+ and AQ preflop. If he has a tight capping range then its meh since its so easy for him to 3-bet his range on this board.

3-betting does make it harder to call down if the board comes out favorably but making a play at this is close imo

yeah

I think trying to steal aggression from the CO by c/r is a mistake. They are not going to fold no matter how good or bad they are. Call down and hope you improve and fold when they bet the river.