Looking at Speedplay pedals, what is the real difference between them?

Is this really that hard to find online? All of the SP lollipops are going to operate the same, differences are going to come down to float, weight, and engagement effort, though not necessarily in that order.

They all seem to come in 3 materials Chrome moly, Stainless, and Titanium (which is rider weight restricted)
but can they not all be locked at no float?
I read where the light action will dissengage easily enough they are NOT recommended for racing, what is X
just the original design?

The X can't be de-floated. The zero can (they have adjustable float). The zero also has a slightly heftier engagement clip. I'm not sure what the light action one is.

I used to use Xs. Now I have two pairs of zeros - a chromo on my spare bike and stainless on my nice one.

Light action are Xs with less float and less clip in force.

Release angle for Lights is 7.5* (Xs is 25-28*)
Float for Lights is 15* (Xs is 20* IIRC)

I love Xs myself. Not recommending for racing is kind of funny...because most pro roadie cyclists are not pulling up on the pedal stroke much at all.

To piggyback off this question: are all speedplay cleats interchangeable? I have X's now but am kinda interested in using Zero's on another bike and don't want to have to switch out my cleats every time...

Cleats and pedals are not interchangable per official literature.

The Light Action and Zero Cleats are interchangeable. My GF has the Light Actions and I have the Zero. I can clip into the LA's just like my Zeros. The LA cleat does not have the float adjustment like the Zero.

Same here. I switched from Xs and now have Stainless Zeros on my road bike and CroMo on my fixie. I definitely prefer being able to lock out some of the float on the Zero cleat over the Xs. I think I was developing some sloppy habits with the Xs.

Ditto - dialing out a bunch of float seemed to help keep one leg in better alignment, particularly when fatigued (and sloppy), and it helped with some knee discomfort that I'd been having.

I had the opposite effect, maybe I have "sloppy habits" lol! I had ridden X/2's for 10+ years. When I went to replace a pair, I decided to try the Zero's and immediately developed some knee discomfort (even with the float opened up), went back to X/2's. I believe Zeros allow the float to be set from 0 to 15 degrees, while the X series has 20+ degrees of float. I really like the X series and can't imagine ever going to a different pedal.

Yeah, I'm pretty sure they're all interchangeable regarding being able to use 1 cleat with all of them as well. I don't think the cleat is different at all between them, just the pedal itself.

Or in my case, to keep the heel of my size 13s from smacking into the chainstay. I should have been 6'3 with these gunboats. I was robbed.

without question get speedplay Zero.

I use Speedplay X's, but I'd reccomend the Zero's to anyone starting fresh.

X's are basically a legacy system that they still make because people like me don't want to switch over multiple bikes with Zero's so we keep replacing the X's one at a time.

The Zero's have better cleat engagement, and less prone to problems from mud/dirt. And given that you can set them open to 15 degrees, virtually no one needs the 20 degrees of the X's.

I had a pair of light actions a year ago. Twice I pulled out when sprinting up a short step hill nearly causing a crash both times. I can also name two others who have experienced the same. Never again will I purchase that model. I've been competing on Speedplays since the later 90's, now strictly on the Zero's.

I did have one of the springs snap on me. It had some decent miles on it. Luckily I was riding the MUP and 20 mins from home.

same here(X Type) but there was about 15,000 miles on the cleat, and it was overdue to be replaced.

True that. I would love to switch to the zeros, but because of the non compatibility issue, I'd also have to get new pedals for my road bike, backup bike, tandem and folder.