For all intents and purposes, Obi committed suicide in ANH when he let Vader kill him. And Yoda's death in ROTJ is suspicious because a few years earlier, he was limber and jumping around at 800 years old. But at 825, he's on his death bed? I'm leaning toward him killing himself. And Vader refused medical care and had Luke take him off life support.

What's the deal with all the suicide in the Jedi ranks?

I'm not a big reader or follower of all the extra nuances of the Star Wars universe, but I have my own ideas about what I have seen over the years. In regards to this kind of Jedi death, I've always leaned more toward the idea of not a killing OR a suicide, but instead allowing themselves, with the help of the Force, to pass into another form, beyond the physical. Beyond that, I couldn't tell you as much as someone who's studied up and kept track of all this.

obi wan became more powerful by "dying"
and yoda was 900 in ESB
"when 900 years old you reach, look as good you'll not"

And im sure all that wonderful food and the surroundings of Dagobah arent the best for one's health. He probably was a little injured too from all the fighting with Sidious, Yoda did take a few good knocks on the head.

Plus Yoda was using the force to shield his presence from Vader and Palp, that took it's toll from him as well.

You're reaching. None of your examples I'd classify as suicide.

Yoda chose Dagobah b/c the darkside presence there would mask him.

I understand what the poster is saying about Obi-Wan and suicide. Technically speaking he did let himself die. However, he could have helped save everyone a lot of time by killing Vader.

How did he become "more powerful" by dying by allowing himself to be killed IF he could have come back anyway if Vader actually did get the better of him? Seems to me that either way he could have come back and whispered sweet nothings in Luke's ear...

I understand your point, but it still ain't suicide.

I think the point is Obi-Wan became immortal. And who can say that Vader wouldn't have killed him anyway? The element of Obi-Wan's choice to die was a component in the immortality concept I believe.

My point is that other Jedi die (without making it their choice) and get to come back as ghosts...Qui Gon...Yoda...Anakin.

The choice element doesn't seem to have anything to do with it.

Actually, he would've doomed the Galaxy had he killed Vader...

Yeap, then Vader would have never killed the Emperior!