Something I’ve been wondering lately, what kind of properties do normal moves that you can kara them into special moves/throws? Why are only those kara-able and not every normal? For example, why can you kara Makoto’s st. LK in 3S and not every other normal she has?
In SF, as a general rule of thumb, all normals are whiff-cancellable into special/super moves on their first few frames of animation. This mechanic is there to add a certain degree forgiveness to overall special/super move execution.
You can kara-cancel all of her ground normals, it’s just that her st.LK is the most (only?) useful one to kara-cancel, as it dislocates you forward on its first few frames (so when you intentionally whiff-cancel the normal, you’ll get the special/super/throw you wanted to do, but with added range). That’s why people kara-karakusa and kara-SA1 with her st.LK.
Oh so that’s how it is. Thanks for the reply!
One myth about kara-cancels: only certain normals are kara-cancellable into moves/throws.
This is not true, as ANY normal in the game can be kara-canceled off of. It’s just some normals make the character move slightly forward or back, which can be beneficial to some characters.
For example, with Makoto, her standing LK can be kara’d much quicker into her regular throw, or she can do it immediately after it sticks out for extra range on her specials(specifically Karakusa, and in extreme cases her SA1 or SA3). Her st.HK moves her backwards, which is important to land her 100% Stun Double Fukiage juggle.
Try karacancelling Chun’s st.HK from far away into her throw. If you look closely, you’ll see the first couple frames of her HK cancel into a throw. Pretty funny to watch. 
Theoretically, normal moves that put you into an airborne (some overheads?) or unique states on the first frame cannot be kara-cancelled. Some special moves can be kara-cancelled and some of the properties that are active on the cancellation frame will get transferred to the new move. This is how the Roll Cancelling glitch worked in CvS2. It happens in SFIV as well, most notably with aerial tatsu’s, burn kicks, Akuma’s Shakunetsu, and EX Armour moves.
Isn’t Chun’s standing HK an airboune move? You can Kara out of that.
Which Chun? Does the move put into an airborne state on the first frame? Is it a true aerial state or is it just the animation that looks like that?
The 3s one.
Well she looks airborne, My bad if I’m wrong.
Probably the first couple frames of her st.HK are on the ground, which is why you can kara-cancel off it.
Mak’s st lk kara isn’t a kara cancel in the traditional sense… it’s a glitch in her short->fwd chain which allows you to substitute the fwd with pretty much any special.
So with a traditional kara your canceling the first frame of the poke into a special while with Mak’s st short your canceling the poke itself in its cancel-able(into st fwd) frames.