Really basic question...

...that I think a lot of pretty decent players probably can't give me an answer to - why am I raising preflop?

Basically, if I'm raising first in it's either because I think I'm ahead of what's going to call me (or if I have AA I want to get re-raised, etc, same idea - value), or I want to get everyone to fold (either right away, or on the flop, or latter), if I don't make a huge hidden monster. This is generally simple enough, but what I don't understand is isolating limpers. Why am I doing this? Obviously position, stack sizes, fold equity, people's limping ranges are all factors, but *how* are they factors? In a nutshell, what am I trying to achieve when I isolate? Obviously it's to get everyone else out of the pot, and play against the limper, because that makes things easier on me, but essentially, when am I doing it for value, and am I doing it for fold equity as often or what?

At the moment I have a starting hand chart in my head (which changes according to table looseness, and stack sizes), and basically I isolate in each position with the same as I would raise first in, minus say the bottom 25% of hands. This seems too rigid, and I'd rather fully understand my goal, and how to achieve, in order that I can make more situation specific decisions.

Basically, raising behind limpers - why?

(I play NL50 6Max)

Well, I dont know why you are, but I covered why I do here:

http://www.flopturnriver.com/phpBB2/...se-t71997.html

Basically, raising behind limpers - why?

You're confusing raising for value with raising to exploit. You raise with the top x% of your unopenned raising range for value. Good hand, want monies. Raising specifically to isolate a limper is done to exploit their weaknesses postflop, which is much easier done HU than multi-way.

We raise because this play is very much +EV. It's +EV in many different ways, some you mentioned. This is going to be talking about raising limpers btw. We obv. need to know their tendencies post flop or even preflop (they limp/fold a lot) and exploit them accordingly. This means if they limp/call a lot preflop and fold to cbets 90% of the time then we show easy profit by isolating/cbetting with ATC. If they limp/call and aggro then we can adjust our range and stack off lighter.

The thing is that if they beat us in one hand, fuck it, just stay at the table and keep playing them. They'll make you very nice money if you figure out how to play each one. Most of them don't know what they are doing really and are either playing their cards (which is so exploitable) or have to win each pot no matter what. In that case, like I mentioned earlier, their range contains much more air and lower pairs that TP is like the nuts and sometimes even a midpair.

I'd suggest figuring out their postflop tendencies and adjust your raising range from that. That said I'd make mine really wide regardless. You'll find a lot of cases that your cards really don't matter.

Besides all this, it's so much better playing vs. just one opponent so we'll be HU more often and the other play at your table who are actually aware will think you are too loose and you can just adjust vs. them and pwn. This is very heavily dependent that THEY adjust though. I'm tired so this is probably bad but whatever.

Anytime you put in money when you have better equity than your opponent, it's +EV (early position raising).

Anytime you can raise and between your pot equity and fold equity be +EV, then you should do so also.

There are multiple reasons to raise preflop, I will try to cover some

1. Raise to isolate - a lot of hands play better vs one or two opponents then multiple opponents (AA/KK) is the classic example, because you rely on the strength of your pocket pair and with multiple opponents there is a good chance someone will improve to 2 pair or better after the flop

2. Raise for value - you have a good hand and you want to have a big pot

3. Raise to pick up the blinds

4. Raise to take control of the pot, as a general rule of thumb people respect raises, so often when you raise preflop you can pick up the pot after the flop when opp misses even if you miss your flops

5. Raise as part of a balanced game strategy (if you only raise your big hands you will not get action when you have them)